Tyre Fitters - Health and Safety Guidelines for - Business.govt.nz
Tyre Fitters - Health and Safety Guidelines for - Business.govt.nz
Tyre Fitters - Health and Safety Guidelines for - Business.govt.nz
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<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong><br />
TYRE FITTERS
The following organisations contributed material which<br />
was used to produce this guideline:<br />
Aim Distributors<br />
B<strong>and</strong>ag New Zeal<strong>and</strong> Limited<br />
Beaurepaires <strong>for</strong> <strong>Tyre</strong>s<br />
BMW New Zeal<strong>and</strong> Limited<br />
Bridgestone/Firestone (NZ) Ltd<br />
Continental Vehicle Distributors Limited<br />
Eastwood Forklift <strong>Tyre</strong>s<br />
Environment Canterbury<br />
Environment Southl<strong>and</strong><br />
Honda New Zeal<strong>and</strong> Limited (LMVD)<br />
Independent <strong>Tyre</strong> Specialists Limited<br />
L<strong>and</strong> Transport <strong>Safety</strong> Authority<br />
Mitsubishi Motors New Zeal<strong>and</strong> Ltd<br />
Motor Trade Association<br />
New Zeal<strong>and</strong> Motor Industry Training Organisation<br />
Oliver <strong>Tyre</strong> & Rubber Co of New Zeal<strong>and</strong> Limited<br />
Powerpac Tools Ltd<br />
Shell New Zeal<strong>and</strong> Limited<br />
South Pacific <strong>Tyre</strong>s NZ Ltd<br />
Tech <strong>Tyre</strong> Repairs Ltd<br />
The <strong>Tyre</strong> General, Temuka<br />
Toyota New Zeal<strong>and</strong> Limited<br />
TRS Agri-Tire Ltd<br />
<strong>Tyre</strong> Seal New Zeal<strong>and</strong><br />
U-Save Partsworld<br />
Upper Hutt <strong>Tyre</strong>s <strong>and</strong> Alignments<br />
Value <strong>Tyre</strong>s Limited<br />
Waihou Engineering<br />
Wellington Motorcycles<br />
Whangarei Truck <strong>and</strong> Tractor Spares<br />
Young Motors Limited<br />
Published by the Occupational <strong>Safety</strong> & <strong>Health</strong> Service<br />
Department of Labour<br />
Wellington<br />
New Zeal<strong>and</strong><br />
www.osh.dol.<strong>govt</strong>.<strong>nz</strong><br />
Published: October 2001<br />
ISBN 0-477-03650-3
Contents<br />
I: Introduction 5<br />
2: Hazards <strong>and</strong> How to Avoid Them 6<br />
Compressed Air ......................................................................................................... 6<br />
Exploding Wheels <strong>and</strong> <strong>Tyre</strong>s ................................................................................... 8<br />
Heavy Objects ............................................................................................................ 9<br />
Noise .......................................................................................................................... 9<br />
3: General <strong>Safety</strong> Rules 10<br />
Choice <strong>and</strong> Care of H<strong>and</strong> Tools ............................................................................. 11<br />
Safe Use of Air Tools.............................................................................................. 12<br />
Safe Lifting ............................................................................................................. 13<br />
Protect Your Hearing.............................................................................................. 13<br />
Measuring Noise ......................................................................................................14<br />
Dressing <strong>for</strong> <strong>Safety</strong> ................................................................................................. 15<br />
Other Equipment .................................................................................................... 15<br />
New Zeal<strong>and</strong> St<strong>and</strong>ards .......................................................................................... 15<br />
Disposal of Anti-freeze ............................................................................................ 16<br />
4: Wheel <strong>and</strong> <strong>Tyre</strong> Identification 17<br />
Passenger Car <strong>Tyre</strong>s ............................................................................................... 18<br />
Light Truck <strong>Tyre</strong>s ................................................................................................... 18<br />
Truck <strong>and</strong> Bus <strong>Tyre</strong>s .............................................................................................. 19<br />
Tractor <strong>Tyre</strong>s .......................................................................................................... 20<br />
Industrial <strong>Tyre</strong>s ...................................................................................................... 21<br />
ATV <strong>Tyre</strong>s ............................................................................................................... 21<br />
5: Points to be Aware of When Fitting <strong>Tyre</strong>s 23<br />
Space Saver <strong>Tyre</strong>s .................................................................................................. 23<br />
Intermixing — General............................................................................................ 23<br />
Intermixing — Passenger Cars ............................................................................... 24<br />
Intermixing — Light <strong>and</strong> Heavy Commercial Vehicles.......................................... 24<br />
Dual <strong>Tyre</strong>s ............................................................................................................... 24<br />
Forkhoist <strong>and</strong> Industrial Vehicles .......................................................................... 25<br />
Forklift Industrial <strong>Tyre</strong>s And Rims ....................................................................... 25<br />
6: Demounting <strong>Tyre</strong>s 29<br />
Removal of Common Assemblies ........................................................................... 29<br />
Light Truck, Truck <strong>Tyre</strong>s — Multi-Piece Rims ...................................................... 30<br />
Demounting Off the Vehicle ................................................................................... 30<br />
Demounting On The Vehicle .................................................................................. 32<br />
7: Repairing <strong>Tyre</strong>s 34<br />
Zipper Hazard ......................................................................................................... 35<br />
Identifying the Hazard ........................................................................................... 35<br />
Inspection ................................................................................................................ 36<br />
Deflating a Zipper................................................................................................... 36<br />
Roadside or Off-Site Servicing ............................................................................... 37<br />
<strong>Safety</strong> Rules <strong>for</strong> Road Side Servicing .................................................................... 38<br />
<strong>Tyre</strong> Sealants .......................................................................................................... 38<br />
8: <strong>Tyre</strong> Mounting <strong>Safety</strong> Precautions 40<br />
To Determine Compatible Rim Width <strong>for</strong> <strong>Tyre</strong> Sizes .......................................... 40
Mounting <strong>Tyre</strong>s ....................................................................................................... 41<br />
Mounting of Common Assemblies <strong>Tyre</strong>s ............................................................... 42<br />
Mounting off the Vehicle ........................................................................................ 44<br />
Mounting on the Vehicle — Agricultural ............................................................... 45<br />
9: Rim <strong>and</strong> Wheel Types 47<br />
Drop Centre or Well Base Rim ...............................................................................47<br />
Flat Base Rims .........................................................................................................47<br />
Wide Base One-Piece Rim ...................................................................................... 48<br />
Multi-Piece Rims ..................................................................................................... 48<br />
Semi-Drop Centre Rim ........................................................................................... 49<br />
Divided Wheels ....................................................................................................... 49<br />
10: Off-the-Vehicle Wheel Balancing 50<br />
11: On-the-Vehicle Wheel Balancing 51<br />
12: Balancing Truck Assemblies 53<br />
13: Roadside <strong>Tyre</strong> Repairs 54<br />
14: <strong>Tyre</strong> Inflation Pressures 56<br />
Free Air Dispensers ................................................................................................ 56<br />
15: Use of Jacks 57<br />
16: <strong>Tyre</strong> <strong>Safety</strong> Cages 58<br />
17: Identifying Vehicles Fitted with Airbags 59<br />
Ways of Identifying Vehicles Fitted with Air Bags............................................... 59<br />
Personal <strong>Safety</strong> ....................................................................................................... 61<br />
The Costs of Accidentally Deploying an Air Bag .................................................. 61<br />
18: The Employer’s Responsibilities 62<br />
Public Access to <strong>Tyre</strong> Change Areas ..................................................................... 63<br />
Working on Sites as a Contractor ......................................................................... 63<br />
19: The Employee’s Responsibilities 64<br />
20: Employee Training Schedule 65<br />
21: Where to Get Advice 66<br />
L<strong>and</strong> Transport Rule: <strong>Tyre</strong>s <strong>and</strong> Wheels .............................................................. 66<br />
<strong>Tyre</strong> <strong>Safety</strong> Issue Boundary Between OSH <strong>and</strong> LTSA ......................................... 66<br />
Web Sites (NZ)........................................................................................................ 66<br />
References ............................................................................................................... 67<br />
Other <strong>Tyre</strong>-Related Web Sites................................................................................ 68<br />
Appendix 1: Wheel Restraint Device 69<br />
Appendix 2: <strong>Tyre</strong> Construction 70<br />
Crossply (or Bias Py) Construction. ...................................................................... 70<br />
Textile Radial Construction .................................................................................... 70<br />
Steel-Belted Radial Construction ........................................................................... 70<br />
Appendix 3: Glossary of Terms 71<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 4
I: Introduction<br />
The Occupational <strong>Safety</strong> <strong>and</strong> <strong>Health</strong> Service has produced this guideline as<br />
part of its continuing drive to reduce the incidence <strong>and</strong> severity of<br />
workplace accidents. It is a guide to safe work methods <strong>and</strong> practices<br />
wherever motor vehicle or industrial tyres are inflated by compressed air.<br />
Accidents while inflating tyres tend to be serious, because of the high air<br />
pressures <strong>and</strong> the heavy objects involved. All too often apprentices or<br />
inexperienced workers are asked to work with tyres without adequate<br />
training or even knowing the risks involved.<br />
Employers must ensure that every tyre fitter is adequately trained, <strong>and</strong><br />
knows, underst<strong>and</strong>s, <strong>and</strong> uses the correct procedures <strong>and</strong> equipment.<br />
Employers are also responsible <strong>for</strong> ensuring that contractors including tyre<br />
fitters operate safely while on their premises. This guide will help employers<br />
underst<strong>and</strong> their duties <strong>and</strong> responsibilities.<br />
<strong>Tyre</strong> fitters must be<br />
adequately trained,<br />
<strong>and</strong> use the correct<br />
procedures <strong>and</strong><br />
equipment.<br />
<strong>Tyre</strong> fitters must use the correct procedures <strong>and</strong> equipment, <strong>and</strong> work in a<br />
way which ensures the safety of themselves, <strong>and</strong> others.<br />
This guide draws on an earlier Department of Labour booklet <strong>Tyre</strong> <strong>Safety</strong>,<br />
which since 1988 has been a st<strong>and</strong>ard reference <strong>for</strong> the tyre industry. It<br />
has been updated to take account of changes in technology <strong>and</strong> new safety<br />
issues such as anticipating zippers in the sudden failure of steel-rein<strong>for</strong>ced<br />
sidewalls, <strong>and</strong> safety rules <strong>for</strong> wheel alignments on vehicles fitted with air<br />
bags. Other health <strong>and</strong> safety issues include the use of antifreeze in tyres,<br />
choice of tyres <strong>and</strong> combinations of tyres. There is additional in<strong>for</strong>mation<br />
on managing hazards of lifting, <strong>and</strong> hazards of noise. We have attempted to<br />
define the boundary between Occupational <strong>Safety</strong> <strong>and</strong> <strong>Health</strong> (OSH) <strong>and</strong><br />
the L<strong>and</strong> Transport <strong>Safety</strong> Authority (LTSA), both regulators with interests<br />
in tyre safety.<br />
This guide has been written with the help of several members of the tyre<br />
industry, <strong>and</strong> people with a professional interest in safe work with tyres. It<br />
is a consensus of what these people consider is safe practice. It does not<br />
have the <strong>for</strong>ce of law, but may be presented to a Court as a statement of<br />
practicable steps in terms of the <strong>Health</strong> <strong>and</strong> <strong>Safety</strong> in Employment Act<br />
1992. In this guide, “shall” indicates that a statement is m<strong>and</strong>atory.<br />
“Should” indicates a recommendation.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> addresses new safety <strong>and</strong><br />
health issues, building on the proven support <strong>for</strong> <strong>Tyre</strong> <strong>Safety</strong>.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 5
2: Hazards <strong>and</strong> How<br />
to Avoid Them<br />
If you work with tyres, there are four major sources of hazard. They are:<br />
• compressed air;<br />
• heavy objects;<br />
• exploding wheels <strong>and</strong> tyres;<br />
• noise.<br />
Compressed Air<br />
Your eyes are particularly at risk, both from high-velocity air <strong>and</strong> from<br />
particles of dust, metal, oil, <strong>and</strong> other debris, which may be propelled by the<br />
air. Always wear suitable eye protection. The rest of your body is also at risk<br />
from compressed air. Suitable overalls will protect the skin from light<br />
particles of debris, provided they are not blown at a high velocity. However,<br />
no overalls can protect you against high-velocity air at close range. Particles<br />
may be blown right through your overalls <strong>and</strong> skin <strong>and</strong> into your body. The<br />
air can be blown straight into your bloodstream, causing swelling <strong>and</strong> intense<br />
pain, particularly if you have any cuts, punctures or sores which make<br />
entry easier. The air may be carried to the small blood vessels of the brain<br />
<strong>and</strong> cause them to burst, resulting in death.<br />
ACCIDENT CASE<br />
Brushing down with compressed air<br />
A worker received a small puncture in the palm of his h<strong>and</strong> from a<br />
metal spike. Soon after he used a compressed air gun to blow dirt <strong>and</strong><br />
blood from his h<strong>and</strong>. The air enlarged the puncture <strong>and</strong> blew up his<br />
h<strong>and</strong> like a small balloon. He suffered severe pain <strong>and</strong> needed hospital<br />
treatment.<br />
All pressure gauges <strong>and</strong> control devices must be checked against a master<br />
pressure gauge at least annually or straight after any heavy impact. Your life<br />
may depend on it.<br />
Compressed air h<strong>and</strong> tools (but not compressors <strong>and</strong> associated equipment)<br />
are exempt from the <strong>Health</strong> <strong>and</strong> <strong>Safety</strong> in Employment (Pressure Equipment,<br />
Cranes, <strong>and</strong> Passenger Ropeways) Regulations 1999 (PECPR Regula-<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 6
tions). Good practice would dictate sound maintenance of such tools <strong>and</strong><br />
monitoring their condition on an ongoing basis.<br />
Compressors must meet<br />
the requirements in the<br />
appropriate code of<br />
practice.<br />
Compressors <strong>and</strong> associated equipment are covered by the draft Code of<br />
Practice <strong>for</strong> the Design, Operation, Maintenance <strong>and</strong> Servicing of Pressure<br />
Equipment. The code will exempt compressors from inspection by an inspection<br />
body, but controllers should consult it <strong>for</strong> other requirements. Receivers<br />
may require inspection, <strong>and</strong> the current requirements can be ascertained<br />
from Table 4.1 of AS/NZS 3788:1996 Pressure equipment - In-service inspection.<br />
Note that any exemption from inspection of an item does not relieve<br />
controllers of their other responsibilities under the PECPR Regulations or<br />
the <strong>Health</strong> <strong>and</strong> <strong>Safety</strong> in Employment Act 1992 or other regulations made<br />
under the Act.<br />
Belt transmissions on compressors shall be guarded — even compressors on<br />
truck decks.<br />
Remember that air under pressure exp<strong>and</strong>s with an increase in temperature.<br />
Never apply heat from a welding torch or any other source to a rim or tyre<br />
which is under pressure. This has caused fatal explosions.<br />
Where possible,<br />
always deflate all<br />
tyres be<strong>for</strong>e removing<br />
them from vehicles.<br />
KEY POINTS<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 7<br />
Where possible, always deflate all tyres be<strong>for</strong>e removing them<br />
from vehicles.<br />
Always remember to store equipment such as air lines properly.<br />
Don’t leave them lying around where they can cause accidents or<br />
get damaged.<br />
Never point an air hose at yourself or anyone else.<br />
Never use damaged air hoses or fittings.<br />
Don’t kink the air hose to stop or cut down the airflow — you<br />
weaken the hose. Use the pressure control <strong>for</strong> adjusting air pressure.<br />
Don’t leave air hoses where vehicles or any other heavy equipment<br />
can run over them, because this can weaken or damage them.<br />
Never leave unattended air lines attached to tyre assemblies.<br />
Never use an air line that is not fitted with a pressure gauge or a<br />
pressure control device.<br />
Check the accuracy of pressure gauges regularly.<br />
Never heat a rim with an inflated tyre on it.
11<br />
12<br />
Compressed air should only be used to inflate tyres or operate<br />
tools.<br />
Compressed air should never be used <strong>for</strong> cleaning. A vacuum<br />
cleaner should be used to clean work areas.<br />
Exploding Wheels <strong>and</strong> <strong>Tyre</strong>s<br />
Large tyres <strong>and</strong> wheel assemblies are heavy objects, but when they explode<br />
they are thrown violently by the <strong>for</strong>ce of the escaping compressed air. An<br />
exploding wheel is a high-speed projectile which can kill or seriously maim<br />
anyone in its path.<br />
ACCIDENT CASE<br />
Broken h<strong>and</strong> when motorcycle tyre over-inflated<br />
The bead of a new tyre would not seat as the fitter was fitting the tyre<br />
to the rear wheel of a motorcycle. He raised the inflation pressure to try<br />
to <strong>for</strong>ce the bead to the corner of the rim; tyre pressure soon reached<br />
420 kPa (60 psi), which was 150% of the maximum pressure. At this<br />
pressure, or slightly more, the tyre bead blew, <strong>for</strong>cing his h<strong>and</strong> against<br />
the chain <strong>and</strong> sprocket with enough <strong>for</strong>ce to break bones in his h<strong>and</strong>.<br />
Divided wheels, split rims <strong>and</strong> locking rings are especially likely to explode<br />
because of poor maintenance, incorrect fitting, <strong>and</strong> assembly or disassembly<br />
while inflated. The most common faults are over-inflation, removal of split<br />
rim fastening nuts instead of wheel fastening nuts, failure to ensure correct<br />
seating of split rims or tyre beads, <strong>and</strong> the use of damaged parts, or parts<br />
with lesser strength than original. Be aware that non-original after market<br />
nuts <strong>and</strong> bolts may be inadequate. It is essential to deflate tyres be<strong>for</strong>e<br />
wheel removal to ensure that removing the wrong nuts does not cause<br />
serious or fatal accidents.<br />
ACCIDENT CASE<br />
Wheelbarrow tyre caused injury<br />
A car tyre or even a wheelbarrow tyre is a potential killer. A tube burst<br />
while a wheelbarrow tyre was being inflated <strong>and</strong> the rim flew up,<br />
striking the worker on the head <strong>and</strong> injuring him.<br />
Zippers expel shrapnel<br />
of rubber <strong>and</strong> steel<br />
which can cause<br />
serious injuries.<br />
Zippers which tear tyre sidewalls expel shrapnel of rubber <strong>and</strong> steel which<br />
can penetrate skin <strong>and</strong> eyes. Escaping air can easily blow tyres across a<br />
workshop with <strong>for</strong>ce.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 8
KEY POINT<br />
Because of the risk of explosion, you must use tyre safety cages, or other<br />
suitable restraining devices, at all times.<br />
Heavy Objects<br />
<strong>Tyre</strong> <strong>and</strong> wheel assemblies of large vehicles are often too heavy to be h<strong>and</strong>led<br />
safely by one person. Even the strongest person can suffer a hernia,<br />
slipped disc, sprain or broken bone when h<strong>and</strong>ling loads that are too heavy.<br />
Such injuries can be very painful <strong>and</strong> limiting.<br />
<strong>Tyre</strong>s may be too<br />
heavy to be lifted by<br />
safely h<strong>and</strong>: get help<br />
or use a mechanical<br />
aid.<br />
KEY POINT<br />
Get help with big loads.<br />
Noise<br />
Given many years of tyre fitting, hearing damage may affect tyre fitters.<br />
Causes are compressed air blowing freely, <strong>and</strong> noise from impact wrenches,<br />
<strong>and</strong> from wheel parts <strong>and</strong> tools dropping on concrete floors. The impact of<br />
steel on concrete floors can be quietened with rubber mats.<br />
KEY POINT<br />
Always wear ear plugs or muffs, because the noise can affect your hearing<br />
long-term.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 9
3: General <strong>Safety</strong><br />
Rules<br />
Make sure you are<br />
familiar with the type of<br />
vehicle, <strong>and</strong> the<br />
procedures required,<br />
be<strong>for</strong>e you begin work.<br />
Here are the general safety rules you should observe at all times:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
Where possible, deflate all tyres especially on divided rims <strong>and</strong><br />
multi-piece rims be<strong>for</strong>e removing them from vehicles.<br />
Don’t wear loose fitting clothing as it can get caught in some<br />
machines.<br />
Don’t start any job <strong>for</strong> which you have not been trained, unless you<br />
are being directly supervised by a person who is both competent<br />
<strong>and</strong> authorised to train you.<br />
Don’t start any job with damaged or unsatisfactory equipment. If<br />
any of the gear to be used, such as air hoses, gauges, mallets, tyre<br />
levers, box spanners, or safety glasses, is not in good working<br />
condition, STOP! Tell your supervisor of the problem immediately,<br />
<strong>and</strong> have it put right.<br />
When starting any repair, ensure you are familiar with the type of<br />
vehicle, <strong>and</strong> the procedures required, be<strong>for</strong>e you begin work.<br />
Is it a farm vehicle, truck, bus, car or industrial tyre. Is it tubeless<br />
or tube-type? Is the rim of a drop centre, semi-drop centre, divided,<br />
two-piece, three-piece type? By this stage you should know whether<br />
or not you have the necessary experience to do the job safely. If<br />
not, STOP! Tell your supervisor that you are not familiar with the<br />
particular tyre. Your supervisor should either refer you to the<br />
correct manuals or wall charts, or provide someone to instruct you.<br />
Correct manuals or wall charts should always be available. Refer to<br />
them whenever you have any doubts. If still in doubt, tell your<br />
supervisor.<br />
Never skylark or play practical jokes in a work area. It is dangerous<br />
<strong>and</strong> will make you liable should you injure anyone.<br />
ACCIDENT CASE<br />
Skylarking with Compressed Air<br />
Two employees were using a compressed air hose to blow dust from<br />
their clothing. One man pushed a hose between the legs of a fellow<br />
worker from behind. The victim’s lower bowel was torn open, his abdomen<br />
ballooned with air <strong>and</strong> he died from his injuries.<br />
NOTE: This incident occurred in a carpenter’s workshop, but the message<br />
is relevant to the tyre industry.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 10
Use a cage guard<br />
when intially inflating<br />
tyres, <strong>and</strong> st<strong>and</strong> well<br />
aside.<br />
8<br />
9<br />
Keep all electrical leads <strong>and</strong> air lines clear of walkways at all times.<br />
They should be coiled <strong>and</strong> stored away when not in use. They<br />
should be inspected each time be<strong>for</strong>e use <strong>and</strong> not used if there is<br />
any sign of damage.<br />
Always use a cage guard or other suitable restraining device when<br />
one is available, even <strong>for</strong> small tyres such as wheelbarrow tyres.<br />
Although not as dangerous as large tyres <strong>and</strong> multi-piece units,<br />
they have still been known to cause serious injuries. Large tyres,<br />
such as truck, bus, grader, tractor tyres, etc., <strong>and</strong> multi-piece units,<br />
must always be isolated in a suitable device during inflation.<br />
ACCIDENT CASE<br />
Inexperienced tyre fitter thrown by exploding tyre<br />
An 18-year-old tyre fitter sat on the tailgate of the service truck while<br />
he waited <strong>for</strong> the truck tyre on the ground beneath him to inflate. He<br />
had only 9 months’ experience, <strong>and</strong> had not previously seen the type<br />
of rim, a trilex type rim, to which he had fitted the tyre. There was no<br />
direct supervision of his service work, <strong>and</strong> he had used his boot instead<br />
of a soft headed hammer to try to seat the rim pieces. Placing the tyre<br />
beneath the tailgate was ineffective, because the tailgate was hinged<br />
<strong>and</strong> able to swivel upwards when the tyre exploded. When the tyre/rim<br />
assembly exploded, he was catapulted 1.8 metres into the air.<br />
10<br />
11<br />
When initially inflating tyres, st<strong>and</strong> well aside.<br />
(a) For car <strong>and</strong> motorcycle tyres, use a clip-on chuck <strong>and</strong> h<strong>and</strong><br />
control device.<br />
(b) For light truck, truck <strong>and</strong> industrial tyres, use a clip-on chuck<br />
<strong>and</strong> 2-metre hose connected to a h<strong>and</strong> control device.<br />
Waste bins <strong>for</strong> rubber or other flammable refuse should have closefitting<br />
lids, <strong>and</strong> should not be used as ashtrays.<br />
KEY POINTS<br />
Make sure that you are safely dressed, use the right equipment <strong>and</strong> have the<br />
right in<strong>for</strong>mation.<br />
Choice <strong>and</strong> Care of H<strong>and</strong> Tools<br />
<strong>Tyre</strong> levers must be kept free of jagged edges <strong>and</strong> rust.<br />
1<br />
2<br />
Hammers are used <strong>for</strong> both mounting <strong>and</strong> demounting tyres. A<br />
rubber end can be used <strong>for</strong> driving on both tyres <strong>and</strong> rims. Always<br />
wear safety goggles when using striking or struck tools. Never use<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 11
a hammer to strike another hammer. Never use a striking tool with<br />
loose or damaged h<strong>and</strong>le. Discard any striking or struck tool if it<br />
shows dents, cracks, chips, or mushrooming.<br />
Safe Use of Air Tools<br />
Always use correct<br />
torque <strong>for</strong> the type of<br />
wheel.<br />
Air tools are mostly used <strong>for</strong> loosening <strong>and</strong> tightening wheel nuts. <strong>Safety</strong> is<br />
essential when using the air tool. If you are not sure, ask your supervisor.<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
11<br />
12<br />
Always wear protective equipment <strong>and</strong> clothing such as eye wear or<br />
a face shield, overalls, gloves <strong>and</strong> other necessary protective clothing.<br />
Use protective barriers where necessary.<br />
When mounting <strong>and</strong> dismounting accessories such as impact<br />
sockets <strong>and</strong> buzz out wheels, make sure to disconnect the tool from<br />
the air line or to shut off the air line.<br />
Always use the correct accessories. Do not use worn, warped <strong>and</strong><br />
damaged accessories.<br />
Always use the correct air hose <strong>and</strong> fittings such as an inlet bushing,<br />
hose nipple <strong>and</strong> hose coupler <strong>and</strong> inspect them regularly <strong>for</strong><br />
wear <strong>and</strong> damage <strong>and</strong> replace when necessary.<br />
Check the air hose <strong>and</strong> connections be<strong>for</strong>e use. (If the hose comes<br />
away while you’re working with the inflator or the air tool, it can<br />
damage the vehicle, or injure you.)<br />
Keep the air hose clear of working parts of the air tool so that it<br />
doesn’t get caught in them.<br />
Check that all attachments are tight be<strong>for</strong>e starting the air tool.<br />
Remember to always disconnect the tool from the air supply when<br />
changing attachments.<br />
Do not use the air hose <strong>for</strong> supporting, lifting or lowering the tool.<br />
Make sure be<strong>for</strong>e use that the tool runs as per its specifications.<br />
The tool should be used according to its capacity <strong>and</strong> only <strong>for</strong> its<br />
own purpose. Do not burst into full speed operation. Avoid any<br />
bumping action <strong>and</strong> excessive pressure.<br />
Do not use the tool in a place which is filled with flammable gas.<br />
Friction or bumping of the tools with the work or another object<br />
may cause sparks <strong>and</strong> there is a possibility that a fire or an explosion<br />
may take place.<br />
Never use or continue to operate the tool when you feel abnormal<br />
vibration, hear unusual sounds, notice unusual changes in speed or<br />
find any other irregularities.<br />
Torque <strong>for</strong> a particular wheel shall be followed. All nuts should be<br />
manually checked <strong>for</strong> torque with a manual wrench.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 12
Safe Lifting<br />
To avoid painful back strains or more serious injury, use a trolley or lifting<br />
equipment where possible or get help.<br />
Even when lifting or picking up light objects, injury can occur if correct<br />
lifting technique is not followed.<br />
When rolling or bowling wheels, always keep them under control. Don’t roll<br />
or bowl them in an uncontrolled manner across the workshop floor, endangering<br />
fellow workers.<br />
KEY POINTS<br />
Always keep wheels<br />
under control when<br />
rolling or bowling<br />
them.<br />
Always get help with<br />
heavy loads.<br />
When you are lifting manually:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
Size up the load. If too heavy or awkward get help. (Extra people<br />
<strong>for</strong> a team lift or use a lifting device.)<br />
Position your feet <strong>for</strong> good balance as close as possible to the object<br />
to be lifted. Crouch as close to the load as possible.<br />
At all times keep your back straight. The bend comes from your<br />
hips <strong>and</strong> knees. Bend at the knees <strong>and</strong> keep your back fairly<br />
straight, not arched.<br />
Get a safe grip using the palms of your h<strong>and</strong>s. When you have a<br />
firm grip on the object with both h<strong>and</strong>s, lift by straightening your<br />
legs.<br />
Don’t jerk or twist your body when lifting or carrying.<br />
Always get help with heavy <strong>and</strong>/or awkward tyres.<br />
REMEMBER: Your back is most at risk when it is bent or twisted.<br />
Protect Your Hearing<br />
Sound is such a common part of life that we take it <strong>for</strong> granted It permits<br />
us enjoyable experiences such as listening to music. It permits us to communicate;<br />
it alerts or warns us — a knock on the door, a siren or alarm, the<br />
chattering valves of a car, a squeaking wheel.<br />
Un<strong>for</strong>tunately long-term exposure to loud sounds can damage our hearing.<br />
Warning signs should<br />
be displayed in noise<br />
hazard areas.<br />
People suffering from occupational deafness experience a distortion of the<br />
sounds they hear. People can no longer distinguish between some words, or<br />
indeed, hear what is being said. Hearing aids offer very limited benefit <strong>for</strong><br />
some people with noise-induced hearing loss.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 13
Some individuals are more sensitive to noise than others <strong>and</strong> will lose<br />
hearing more readily through noise exposure.<br />
Management of the hazards of noise, <strong>and</strong> a technical description of noiseinduced<br />
hearing loss, can be found in the Approved Code of Practice <strong>for</strong><br />
Management of Noise in the Workplace.<br />
Measuring Noise<br />
Sound is measured in decibels or dBA.<br />
If you are exposed continuously to sounds of 85 dBA over an 8-hour day,<br />
this can lead to hearing damage if hearing protection is not worn. Repeated<br />
long-term daily exposure <strong>for</strong> 1 or 2 hours per day to sounds of more than 90<br />
dBA can lead to hearing damage if protection is not worn.<br />
If you are using an impact gun to loosen wheel nuts, or are st<strong>and</strong>ing next to<br />
a noisy compressor, the noise level can be well over 90 dBA. Hitting metal<br />
objects with a hammer, or dropping steel tyre levers on to concrete floors,<br />
can produce very loud sounds that may lead to hearing damage.<br />
Compressed air blown from a hose can be loud, especially when it strikes a<br />
solid edge.<br />
As the noise level gets higher, damage will occur over a shorter period.<br />
Noise from an impact<br />
gun can damage your<br />
hearing: always use<br />
hearing protectors.<br />
ARE YOU AT RISK?<br />
Fill out this simple quiz to see if your hearing is at risk.<br />
1. At work, do you have to shout to make yourself understood by somebody<br />
about an arm’s length away?<br />
YES<br />
N O<br />
2. Do you get ringing or buzzing in your ears after work, or after particular<br />
jobs at work?<br />
YES<br />
N O<br />
3. Does your family say you have difficulty hearing them when you get<br />
home?<br />
YES<br />
N O<br />
4. Do you have to turn up the volume on the TV or radio after a day at<br />
work?<br />
YES<br />
N O<br />
5. Do you often have to ask people to repeat things they’ve just said?<br />
YES<br />
N O<br />
If you have answered “YES” to any of these questions, chances are that<br />
noise in your workplace could be putting your hearing at risk.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 14
KEY POINT<br />
Compressed air <strong>for</strong> blowing should come from low-pressure air lines, using<br />
special nozzles. Hearing protection must be worn while using impact tools.<br />
Dressing <strong>for</strong> <strong>Safety</strong><br />
One way to help prevent injury at work is to dress safely. Employers have a<br />
duty to provide suitable protective clothing <strong>and</strong> equipment. Workers have a<br />
duty to wear <strong>and</strong> use it.<br />
A typical lace-up<br />
safety shoe with<br />
protective toe cap.<br />
A leather glove with<br />
gel-filled palm to<br />
protect against<br />
vibration. Designed<br />
<strong>for</strong> use with medium<br />
to high-impact tools.<br />
The minimum requirements when working with or fitting tyres are:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
Industrial overalls, which should be close fitting (particularly<br />
around the wrists) <strong>and</strong> worn fastened to the neck. Sleeves should<br />
be kept down, not rolled up.<br />
Eye protection is essential. Your eyesight is precious; an accident<br />
could blind you <strong>for</strong> life. Various types of goggles or visors are<br />
satisfactory, but if spectacles are used, they must be fitted with<br />
side shields.<br />
<strong>Safety</strong> footwear with protective toecaps, which is necessary when<br />
h<strong>and</strong>ling heavy items such as truck, grader, bus, or other large<br />
vehicle wheels <strong>and</strong> tyres. Even where only light car wheels <strong>and</strong><br />
tyres are h<strong>and</strong>led, footwear must be adequate. Wearing thongs,<br />
s<strong>and</strong>als, s<strong>and</strong>shoes or other similar footwear is unsafe <strong>and</strong> may<br />
cause unnecessary injuries.<br />
Hearing protection must be worn when working with or near<br />
impact guns or noisy equipment, including some compressors.<br />
Knee pads will protect your knees from injury when kneeling on<br />
hard or rough surfaces.<br />
Gloves help protect your h<strong>and</strong>s from injury. Wear gloves when<br />
h<strong>and</strong>ling sharp tools or checking <strong>for</strong> punctures. Sharp objects<br />
protruding from tyres can cut h<strong>and</strong>s.<br />
High-visibility clothing (fluorescent vests) must be worn by fleet<br />
service persons when working on the roadside.<br />
Example of hivisibility<br />
vest,<br />
suitable <strong>for</strong> day or<br />
night conditions.<br />
Other Equipment<br />
Other equipment may be necessary in particular circumstances. Only the<br />
correct hammers, levers, lubricants, bolts, <strong>and</strong> other tools are to be used.<br />
Never use equipment that you know or suspect is faulty or inadequate.<br />
Report the fault or inadequacy to your supervisor.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 15
New Zeal<strong>and</strong> St<strong>and</strong>ards<br />
No protective clothing or equipment is suitable unless it provides adequate<br />
protection from the particular hazards likely to be met. The New Zeal<strong>and</strong><br />
St<strong>and</strong>ards Association has produced a range of st<strong>and</strong>ards <strong>and</strong> specifications<br />
<strong>for</strong> protective clothing <strong>and</strong> equipment. The Occupational <strong>Safety</strong> <strong>and</strong> <strong>Health</strong><br />
Service (OSH) recommends that all clothing <strong>and</strong> equipment comply with the<br />
relevant st<strong>and</strong>ard where one exists. There are New Zeal<strong>and</strong> St<strong>and</strong>ards <strong>for</strong><br />
eye protection, overalls, safety footwear, industrial gloves, <strong>and</strong> many other<br />
types of equipment. All products accepted as complying with the New Zeal<strong>and</strong><br />
St<strong>and</strong>ard, or a suitable overseas st<strong>and</strong>ard accepted <strong>for</strong> use in New<br />
Zeal<strong>and</strong>, will bear a St<strong>and</strong>ard Certification Mark. Further in<strong>for</strong>mation may<br />
be obtained from the St<strong>and</strong>ards Association of New Zeal<strong>and</strong>.<br />
Disposal of Antifreeze<br />
Antifreeze is likely to be present in water-filled tractor tyres used in cold<br />
climates. Ethylene glycol is a highly toxic chemical used <strong>for</strong> antifreeze.<br />
Antifreeze solution could create h<strong>and</strong>ling <strong>and</strong> disposal problems. When<br />
draining antifreeze solution, keep in mind that cats <strong>and</strong> dogs are attracted<br />
by the ethylene glycol, <strong>and</strong> are likely to drink any that is left in an uncovered<br />
container or in puddles on the ground. Even small quantities swallowed<br />
will be fatal.<br />
Draining should occur on an area of sealed ground as antifreeze drained on<br />
to broken ground is likely to contaminate the property or groundwater.<br />
Spills should be contained with absorbent material <strong>and</strong> the advice of the<br />
territorial local authority sought to arrange disposal.<br />
Antifreeze is often<br />
added to the water in<br />
water-filled tractor<br />
tyres in cold climates.<br />
Always drain the antifreeze into a clean <strong>and</strong> uncontaminated sealable container.<br />
The container should be labelled <strong>and</strong> dated <strong>for</strong> future identification,<br />
<strong>and</strong> stored in a clean, dry <strong>and</strong> secure place where spills can be contained.<br />
Antifreeze should be reused unless it is contaminated or several years old.<br />
Ethylene glycol will also be present in a number of tyre sealants.<br />
Disposal of antifreeze in the sewage system or in septic tanks may only<br />
occur if it is authorised, <strong>and</strong> requires consent from your Territorial Local<br />
Authority. Antifreeze <strong>for</strong> disposal in sewers must be diluted to 20% to 30%;<br />
15% or less <strong>for</strong> disposal in septic tanks. Antifreeze must not be disposed of<br />
in storm water or allowed to enter streams. Ask your local authority or<br />
regional council about correct disposal.<br />
Some tractors used in cold climates have methylated spirits as an antifreeze<br />
in the tyres. Methylated spirits (or other hydrocarbons) should be placed in<br />
sealed containers, but should not be used in tyres. In small quantities,<br />
volatile hydrocarbons may be disposed of by evaporation, by placing them in<br />
an open nonporous container in a secure well-ventilated area.<br />
Some farmers add calcium chloride to tyre ballast water. Water containing<br />
calcium chloride is more dense than pure water. Calcium chloride lowers the<br />
freezing point <strong>and</strong> acts as anti-freeze. For advice on disposal, ask your<br />
Territorial Local Authority.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 16
4: Wheel <strong>and</strong> <strong>Tyre</strong><br />
Identification<br />
Always be sure that a tyre is mounted on to the correct size <strong>and</strong> type of<br />
rim. It is dangerous to install a tyre of one rim diameter on a rim of a<br />
different diameter. Also, you should never mount or use damaged tyres,<br />
tubes or rims. Always replace a tyre on a rim with another tyre of exactly<br />
the same rim diameter designation <strong>and</strong> suffix letters. For example a 16-inch<br />
tyre goes with a 16-inch rim. You should never mount a 16-inch diameter<br />
tyre on a 16.5-inch rim. It may be possible to pass the tyre over the lip or<br />
flange of the rim but the tyre cannot be inflated enough to position itself<br />
against the rim flange. If you attempt to seat the tyre bead by inflation, it<br />
will break with explosive <strong>for</strong>ce <strong>and</strong> could cause serious injury or death.<br />
Markings show rim<br />
width <strong>and</strong> diameter in<br />
inches.<br />
ACCIDENT CASE<br />
Exemplary damages: mismatching tyre <strong>and</strong> rim<br />
During the fitting of a new 15-inch tyre in the defendant’s tyre bay, the<br />
plaintiff was severely injured when the tyre exploded on the 15.3 inch<br />
wheel rim as the tyre was being inflated. The plaintiff’s injuries were<br />
severe — he suffered severe shock; intra-abdominal bleeding <strong>and</strong><br />
injury to his liver; lacerations to his scalp; puncture wound over the left<br />
shoulder; a closed displaced fracture of the left arm; compound<br />
fracturing of the shafts of the second, third <strong>and</strong> fourth fingers of his left<br />
h<strong>and</strong>; crushed <strong>and</strong> fractured ribs; left leg almost severed through the<br />
knee, <strong>and</strong> some unspecified brain damage.<br />
The plaintiff was awarded exemplary damages.<br />
KEY POINT<br />
Rims of different diameters <strong>and</strong> tapers cannot be interchanged. Diagrams<br />
below illustrate the difference between rims of two different tapers <strong>and</strong><br />
diameters.<br />
Diagrams show the<br />
difference between correct<br />
<strong>and</strong> incorrect seating <strong>for</strong><br />
different combinations of<br />
tyres <strong>and</strong> rims.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 17
Passenger Car <strong>Tyre</strong>s<br />
In general, tyres have two basic size markings. These indicate the section<br />
width of the tyre (when fitted to its design rim) <strong>and</strong> the rim diameter on<br />
which it fits. Crossply car tyres are normally designated in inches, <strong>for</strong><br />
example a 6.50 - 13 is a tyre nominally 6.50-inch wide fitting a 13-inch rim.<br />
Radial car tyres are normally designated in millimetres <strong>and</strong> inches with the<br />
letter “R”: <strong>for</strong> example, a 175R13 is a radial tyre nominally 175 mm wide<br />
fitting a 13-inch rim. This marking alone, however, does not indicate the<br />
shape which a tyre takes up on the rim, <strong>and</strong> it is this factor which has<br />
changed considerably in recent years. <strong>Tyre</strong>s have become smaller in diameter<br />
but at the same time much wider in section, i.e. more “squat”. Great<br />
care should be taken when selecting tyres to ensure that the correct size<br />
<strong>and</strong> type are being fitted.<br />
Crossply<br />
6.50 - 13 6PR<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Nominal section width (inches)<br />
Radial 185 S R 14<br />
P 185/60 R 14 82 H<br />
220/65 R 390 97 V<br />
Nominal rim diameter (inches)<br />
Radial<br />
Speed rating symbol<br />
Nominal section width (mm)<br />
Speed rating symbol<br />
Load index<br />
Nominal rim diameter (inches)<br />
Radial<br />
Nominal aspect ratio (%)<br />
Nominal section width (mm)<br />
Passenger tyre<br />
Speed rating symbol<br />
Load index<br />
Nominal rim diameter (mm)<br />
Radial<br />
Nominal aspect ratio (%)<br />
Nominal section width (mm)<br />
Light Truck <strong>Tyre</strong>s<br />
7.50 - 16 10PR<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Nominal section width (inches)<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 18
31 x 10.50 R 15<br />
195 R 14 LT or C<br />
LT 235/85 R 16 115/113 L<br />
Nominal rim diameter (inches)<br />
Radial<br />
Approximate section width (inches)<br />
Approximate overall diameter (inches)<br />
Light truck or commercial<br />
Nominal rim diameter (inches)<br />
Radial<br />
Nominal selection width (mm)<br />
Speed rating symbol<br />
Load index - single/dual<br />
Nomination rim diameter (inches)<br />
Radial<br />
Nominal aspect ratio (%)<br />
Nominal section width (mm)<br />
Light truck tyre<br />
Truck <strong>and</strong> Bus <strong>Tyre</strong>s<br />
These are normally marked in a similar manner to car tyres, <strong>for</strong> example:<br />
• 10.00 - 20 is a crossply tyre but a 10.00R20 is a radial ply tyre.<br />
Both have a nominal section marking of 10 inch <strong>and</strong> fit a 20-inch<br />
rim.<br />
• 11 - 22.5 is a crossply tyre but a 11R22.5 is a radial ply tyre. Both<br />
have a nominal section marking of 11 inch <strong>and</strong> fit a 22 1 /2 --inch rim.<br />
The ‘22.5' tyres are of tubeless construction <strong>and</strong> have a tubed tyre<br />
counterpart. For example 9.00R20 <strong>and</strong> a 10R22.5 have similar<br />
outside dimensions <strong>and</strong> the same load capacity, but the first is a<br />
tubed type <strong>and</strong> the second tubeless.<br />
• Check the tyre <strong>for</strong> these markings on the sidewall.<br />
Crossply - or x between markings<br />
Radial tubed or tubeless<br />
10.00 R 20 16PR<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Radial construction<br />
Nominal section width (inches)<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 19
11 R 22.5 16PR<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Radial construction<br />
Nominal section width (inches)<br />
295/80 R 22.5 149/146 L<br />
Speed Rating<br />
Load index - single/dual<br />
Nominal rim diameter (inches)<br />
Radial construction<br />
Nominal aspect ratio (%)<br />
Nominal section width (mm)<br />
Tractor <strong>Tyre</strong>s<br />
These come in two types of markings or a combination of both, the difference<br />
being a change in nominal section width when tyres started to be<br />
fitted to wider rims. For example:<br />
• 14 - 30 where 14 Section marking 30-inch diameter, or<br />
• 16.9 - 30 where 16.9 Section width on wide-base rim 30-inch diameter, or<br />
• 16.9/14 - 30 Dual size marking<br />
18.4 - 30 8PR<br />
18.4 R 30 142 A8<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Nominal section width (inches)<br />
Speed rating symbol<br />
Load index<br />
Nominal rim diameter (inches)<br />
Radial<br />
Nominal section width (inches)<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 20
520/70 R 30 151 D<br />
Speed rating symbol<br />
Load index<br />
Nominal rim diameter (inches)<br />
Radial<br />
Nominal aspect ratio (%)<br />
Nominal section width (mm)<br />
Industrial <strong>Tyre</strong>s<br />
21 x 8 - 10 14PR<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Nominal section width (inches)<br />
Nominal overall diameter (inches)<br />
405 x 130 - 305<br />
Nominal rim diameter (mm)<br />
Nominal section width (mm)<br />
Nominal overall diameter (mm)<br />
10.00 - 20 16PR IND<br />
Industrial construction<br />
Ply rating<br />
Nominal rim diameter (inches)<br />
Nominal section width (inches)<br />
ATV <strong>Tyre</strong>s<br />
AT 22 x 8 - 10<br />
Nominal rim diameter (inches)<br />
Nominal section width (inches)<br />
Nominal overall diameter (inches)<br />
All terrain<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 21
TYRE RATINGS<br />
RATING / SPEED<br />
J 100 KPH Q 160 KPH<br />
K 110 KPH R170 KPH<br />
L 120 KPH S 180 KPH<br />
M 130 KPH T 190 KPH<br />
N 140 KPH U 200 KPH<br />
P 150 KPH H 210 KPH<br />
For higher speeds:<br />
V<br />
•W<br />
•Y<br />
240 kph<br />
270 kph<br />
300 kph<br />
• For tyres having a maximum speed capability of more than 240 kph,<br />
a ZR may appear in the size designation. For tyres having a maximum<br />
speed capability greater than 300 kph, a ZR must appear in the size<br />
designation.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 22
5: Points to be Aware<br />
of When Fitting <strong>Tyre</strong>s<br />
KEY POINT<br />
These recommendations apply regardless of whether the vehicle is front- or<br />
rear-wheel drive, front or rear-engined.<br />
Space Saver <strong>Tyre</strong>s<br />
Space saver is the term commonly used to describe temporary-use spare<br />
tyres. Their smaller size reduces storage space requirements <strong>and</strong> weight,<br />
hence the name. Unlike a st<strong>and</strong>ard spare tyre their use is <strong>for</strong> emergency<br />
purposes only, <strong>and</strong> strictly in accordance with the safety instructions<br />
attached to the wheel. The most common wheels are normally in bright or<br />
contrasting colours, with tyres about the width of a motorcycle tyre.<br />
Space saver tyres<br />
should only be used in<br />
an emergency.<br />
Space saver tyres should only be used in an emergency to get the driver<br />
directly home or to a place to get the regular tyre repaired <strong>and</strong> refitted to<br />
the vehicle. Space saver tyre users should also be careful to comply with the<br />
tyre’s inflation requirements (commonly about 350 - 420 kPa (50 - 60 psi),<br />
i.e. much higher than a normal car tyre) <strong>and</strong> speed restriction (maximum 80<br />
kph). If drivers follow these guidelines, <strong>and</strong> their space saver tyre is in good<br />
condition, it’s safe to drive on.<br />
However, you need to remember that the vehicle’s h<strong>and</strong>ling may be affected<br />
when a space saver tyre is fitted. Never fit more than one space saver tyre<br />
to a vehicle.<br />
Intermixing - General<br />
All steering wheel movements produce lateral <strong>for</strong>ce on the tyres. The reaction<br />
of a tyre to these lateral <strong>for</strong>ces varies according to its structure. There<strong>for</strong>e,<br />
<strong>for</strong> interchangeability of tyres without modification of the vehicle<br />
h<strong>and</strong>ling characteristics, it is necessary to take into account the tyre size<br />
<strong>and</strong> construction. Ideally, tyres should be in complete sets of the same type<br />
<strong>and</strong> construction. Some intermixing is allowable, however, while other<br />
combinations are either not recommended or not permitted. Basic rules:<br />
<strong>Tyre</strong>s <strong>and</strong> rims must always be matched.<br />
1<br />
2<br />
<strong>Tyre</strong> tread patterns fitted to the same vehicle axle should be<br />
matched. <strong>Tyre</strong>s on the same axle shall be of the same nominal size<br />
<strong>and</strong> be of similar construction.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 23
Unidirectional tyres<br />
must be fitted so that<br />
they rotate in the<br />
direction of the arrow.<br />
3<br />
4<br />
5<br />
6<br />
Unidirectional tyres must be correctly fitted so that when the wheel<br />
is fitted to the vehicle, the direction of rotation as indicated by the<br />
arrow moulded into the tyre side wall is <strong>for</strong>ward.<br />
Asymmetric tread tyres must be fitted the right way round on the<br />
rim so that the respective side walls are in contact with the correct<br />
side of the rim. These must be fitted so that the “outside” sidewall<br />
marking is facing outward.<br />
It is recommended that all the tyres fitted to a light vehicle be<br />
either bias-ply or radial ply construction <strong>and</strong> not a mix of both.<br />
Should this become a m<strong>and</strong>atory requirement in the proposed L<strong>and</strong><br />
Transport Rule: <strong>Tyre</strong>s <strong>and</strong> Wheels, 5.1 <strong>and</strong> 5.2 will be omitted.<br />
5.1 If crossply <strong>and</strong> radial tyres are mixed, the radials must be<br />
fitted to the rear axle.<br />
5.2 If textile radial <strong>and</strong> steel radial tyres are mixed, the steel<br />
radial should be fitted to the rear axle.<br />
If radial tyres of different aspect ratio are mixed, the tyres of<br />
lowest aspect ratio must be fitted to the rear axle.<br />
Intermixing - Passenger Cars<br />
In addition to the conditions above, this condition applies:<br />
1<br />
2<br />
If a space saver has been fitted <strong>for</strong> emergency use, the space saver<br />
must be returned to the spare wheel position as soon as possible.<br />
Only one space saver shall be fitted to a car at a time.<br />
Intermixing - Light <strong>and</strong> Heavy Commercial Vehicles<br />
In addition to the conditions above, these conditions apply:<br />
1<br />
2<br />
<strong>Tyre</strong> tread patterns fitted to the same vehicle axle should be<br />
matched. <strong>Tyre</strong>s on the same axle shall be of the same nominal size<br />
<strong>and</strong> be of similar construction.<br />
Radial tyres may only be fitted to the front of a vehicle with<br />
crossply rear tyres if the rears are duals.<br />
NOTE: Care should be taken to ensure that any interchanging of<br />
wheels does not result in incorrect fitments.<br />
Dual <strong>Tyre</strong>s<br />
<strong>Tyre</strong>s paired as duals require special treatment to ensure maximum potential<br />
mileage, regular wear <strong>and</strong> safety to both operator <strong>and</strong> tyre service<br />
persons.<br />
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• Correct Spacers <strong>and</strong> Wheel Offsets<br />
Ensure that correct spacer b<strong>and</strong>s or correct offset wheels are used that<br />
provide adequate clearance between tyres <strong>and</strong> minimise trapping of stones<br />
<strong>and</strong> other objects. Be careful not to over-tighten artillery-style wheels as<br />
spacers can become de<strong>for</strong>med <strong>and</strong> buckled.<br />
• Mixing of Patterns or Constructions<br />
For maximum safety<br />
<strong>and</strong> efficiency, dual<br />
wheels require special<br />
treatment.<br />
Mismatching of tyres can have a profound effect on tyre life. Radial <strong>and</strong><br />
crossply constructions should not be dualled together, nor should rib <strong>and</strong> lug<br />
tyres, as irregular wear will develop <strong>and</strong> tyre life will be adversely effected.<br />
• Permissible Diameter Differences<br />
It is important that dualled tyres are of the same size (diameter) otherwise<br />
the larger tyre will be overloaded <strong>and</strong> the smaller tyre, lacking proper road<br />
contact, wears faster <strong>and</strong> irregularly. <strong>Tyre</strong>s mounted in duals must be<br />
matched so that the maximum difference between the diameters of the tyres<br />
does not exceed 6 mm. This may be measured by using either a square or<br />
matching stick. The larger tyre should always be mounted on the outside<br />
position as road camber produces least loading on this position.<br />
• Matched Inflation Pressures<br />
It is important to ensure that both tyres on a dual tyre assembly have<br />
matched inflation pressures. Mismatched pressures result in the<br />
underinflated tyre wearing faster <strong>and</strong> irregularly, <strong>and</strong> the correctly inflated<br />
tyre becoming overloaded, with an increase of heat <strong>and</strong> probability of premature<br />
tyre failure.<br />
Forkhoist <strong>and</strong> Industrial Vehicles<br />
Only purpose-designed industrial tyres that are approved by the vehicle<br />
manufacturer <strong>and</strong> approved <strong>for</strong> the rim specification may be fitted.<br />
For vehicles such as agricultural tractors <strong>and</strong> other low-speed vehicles where<br />
radial <strong>and</strong> crossply tyres are fitted to the same vehicle, it is recommended<br />
that the radial <strong>and</strong> crossply tyres be fitted to different axles <strong>and</strong> not mixed<br />
on the same axle.<br />
Forklift Industrial <strong>Tyre</strong>s And Rims<br />
This section outlines some of the requirements to be met by the <strong>for</strong>klift<br />
owner/driver, the tyre fitter <strong>and</strong> the tyre/rim supplier.<br />
<strong>Safety</strong> Rules<br />
1<br />
Always remove valve core <strong>and</strong> fully deflate <strong>for</strong>klift tyres prior to<br />
removing the wheel nuts, especially on divided or bolt-together<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 25
Never try to remove<br />
the split rim fastening<br />
nuts instead of the<br />
wheel fastening nuts<br />
— this has caused<br />
fatalities.<br />
2<br />
3<br />
4<br />
rims. When reassembling divided/bolt-together rims, where possible,<br />
ensure the rim bolt-together bolts are fitted with the bolt heads<br />
facing outwards. This practice helps differentiate between the<br />
<strong>for</strong>klift wheel nuts <strong>and</strong> the rim bolt-together bolts.<br />
Always follow industry-approved safety precautions <strong>for</strong> deflation,<br />
removal, fitment, inspection <strong>and</strong> inflation of pneumatic tyres.<br />
Always use the correct tools <strong>and</strong> safety equipment when servicing<br />
<strong>for</strong>klift tyres. For guidance, see the previous two pages.<br />
Always obtain the correct in<strong>for</strong>mation <strong>for</strong> the rim or tyre from the<br />
product manufacturer, or their designated representative. All<br />
reputable manufacturers produce specification in<strong>for</strong>mation on their<br />
products.<br />
Always consult the <strong>for</strong>klift manufacturer be<strong>for</strong>e altering any tyre<br />
specification on a <strong>for</strong>klift. You must ensure the rated load carrying<br />
capacity <strong>and</strong> stability of the <strong>for</strong>klift will not be affected.<br />
ACCIDENT CASE<br />
Divided wheel flew apart<br />
A worker was replacing the outside wheel of a dual-wheel assembly on<br />
a <strong>for</strong>klift. He noticed that the nuts of the six bolts holding the two halves<br />
of the divided wheel together were round the wrong way <strong>and</strong> the<br />
wheel couldn’t fit properly. He attempted to remove the bolts one at a<br />
time without deflating the tyre. The rim blew off <strong>and</strong> struck him on the<br />
<strong>for</strong>ehead. He died in hospital 9 hours later. The wheel had a warning<br />
about this practice stamped on it.<br />
General Requirements<br />
After deflation <strong>and</strong> tyre removal, clean <strong>and</strong> inspect rim <strong>and</strong> components <strong>for</strong><br />
cracks <strong>and</strong> de<strong>for</strong>mation. If in doubt, discard rim assembly. Check nuts, bolts<br />
<strong>and</strong> washers used in divided or bolt-together rims. If any are damaged,<br />
always replace them as a set with the correct grade <strong>and</strong> size.<br />
Never mix <strong>and</strong> match multi-piece rim components. Always ensure that all of<br />
the components are correctly fitted to the rim when reassembling. The bead<br />
seat (or advance) b<strong>and</strong> must be fitted, if the rim is designed to have one. If<br />
the rim is designed to have a bead seat b<strong>and</strong>, <strong>and</strong> it is missing, this is a<br />
valid reason to reject the rim.<br />
Most divided rims are only rated to 690 kPa (6.90 bar = 100 psi). This<br />
makes them unsuitable <strong>for</strong> radial <strong>for</strong>klift tyre fitment due to their higher<br />
inflation pressure requirement of 900 to 1000 kPa (9.00 to 10.00 bar = 130<br />
to 145 psi). Only rims certified <strong>for</strong> 1000 kPa (10 bar = 145 psi) cold inflation<br />
pressures are suitable <strong>for</strong> radial <strong>for</strong>klift tyre fitment.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 26
KEY POINTS<br />
Only industrial <strong>for</strong>klift tyres, normally marked NHS (nonhighway service), are<br />
suitable <strong>for</strong> fitment to <strong>for</strong>klifts.<br />
Truck tyres, even though they may have the same tyre size <strong>and</strong> ply rating,<br />
must not be fitted.<br />
Example:<br />
10.00 - 20 14-ply truck tyre at 700 kPa (7.0 bar = 102 psi) is rated to carry a<br />
load of 2575 kg per tyre in a dual fitment situation.<br />
10.00 - 20 14-ply <strong>for</strong>klift tyre at 700 kPa, due to its heavier construction, is<br />
rated to carry a load of 5640 kg per tyre in a dual fitment situation.<br />
The sum of the load capacity of all the tyres fitted to a <strong>for</strong>klift must not be<br />
less than the gross mass of the <strong>for</strong>klift (this includes the weight of the<br />
<strong>for</strong>klift <strong>and</strong> its maximum rated load) at the maximum speed of which the<br />
<strong>for</strong>klift is capable.<br />
Operational requirements as set by the <strong>for</strong>klift manufacturer must be met,<br />
such as correct tyre type, inflation pressure, ply rating <strong>and</strong> rim type.<br />
Most <strong>for</strong>klift manufacturers rate their <strong>for</strong>klifts, <strong>for</strong> stability <strong>and</strong> load-carrying<br />
capacity on industrial cross-ply pneumatic tyres, industrial cushion or<br />
resilient tyres. Be<strong>for</strong>e altering the tyre construction type, <strong>for</strong> example, crossply<br />
to radial, the <strong>for</strong>klift manufacturer must be consulted, as this may affect<br />
the stability or load-carrying capacity of the <strong>for</strong>klift.<br />
Cushion solid (resilient) tyres can be fitted to all <strong>for</strong>klift rims. Irreparable<br />
damage can be caused to rims <strong>and</strong> tyres if correct tyre to rim fitment<br />
techniques are not adhered to. Proper pressing equipment is required to<br />
ensure damage-free fitment of tyre to rim.<br />
When replacing worn or damaged <strong>for</strong>klift rims, ensure that the replacement<br />
rim is designed to carry the load <strong>and</strong> pressure of the tyre. Never add or<br />
remove an attachment from, or otherwise modify, a <strong>for</strong>klift rim. Never weld<br />
a cracked rim. Never apply heat, weld or brazing to a rim, unless the tyre<br />
has been removed, <strong>and</strong> approval has been received from the rim manufacturer.<br />
Modification or heating of a rim or one of its components may<br />
weaken it so that it cannot withst<strong>and</strong> <strong>for</strong>ces created by inflation or operation.<br />
Components of multi-piece rims wear during their service life. Do not<br />
replace worn or damaged components with new ones <strong>and</strong> fit to a worn rim<br />
base. Fitting new components onto an old rim base could cause DEATH or<br />
INJURY because the new components may not lock in or seat properly. If in<br />
any doubt, <strong>for</strong> safety’s sake, reject the rim.<br />
<strong>Tyre</strong> Wear Limits<br />
There are no national or international st<strong>and</strong>ards <strong>for</strong> the limits of tyre wear<br />
<strong>for</strong> <strong>for</strong>klifts, but some manufacturers give guidance which is usually re-<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 27
stricted to their own products. The tyre manufacturer’s recommendations<br />
should always be followed.<br />
Cushion solid (resilient) tyres have a 60J or safety line around the circumference.<br />
This safety line signifies the maximum wear limits of the tyre.<br />
Pneumatic tyres should be inspected daily <strong>for</strong> cuts, cracks <strong>and</strong> wear. If any<br />
part of the tyre carcass is exposed, the tyre must be replaced immediately.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 28
6: Demounting <strong>Tyre</strong>s<br />
Vehicle jacked with<br />
wheel off — ready <strong>for</strong><br />
tyre replacement.<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
Be<strong>for</strong>e deflation, read <strong>and</strong> chalk the tyre pressure on the tyre wall.<br />
Take special note of any tyre with 80% or less of recommended<br />
pressure.<br />
When any wheel or tyre is in a damaged condition, remove the<br />
valve core completely to deflate the tyre be<strong>for</strong>e you take the wheel<br />
off the vehicle.<br />
Don’t remove any tyre from a wheel rim unless you have removed<br />
the valve core <strong>and</strong> are sure the tyre is fully deflated. Remove both<br />
valve cores from a dual assembly.<br />
Always exhaust all air from a single tyre, <strong>and</strong> from both tyres of a<br />
dual assembly, be<strong>for</strong>e you remove any rim or wheel components<br />
such as nuts <strong>and</strong> rim clamps.<br />
Always check the valve stem, by running a piece of wire through<br />
the stem to be sure that it is not plugged.<br />
Always wear suitable eye protection while removing tyres from<br />
rims.<br />
Removal of Common Assemblies<br />
Car, Van <strong>and</strong> Tractor <strong>Tyre</strong>s — Well-base Rims<br />
Remove valve core <strong>and</strong> completely deflate tyre.<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
Disengage the valve core from the rim (tube type).<br />
Unseat both tyre beads using the correct h<strong>and</strong> tools or with pneumatic,<br />
hydraulic, or mechanical equipment. Be sure to follow the<br />
instructions supplied.<br />
Lubricate the rim flange <strong>and</strong> tyre bead areas, using an approved<br />
tyre bead lubricant.<br />
With the narrow rim ledge facing upwards, pry the top tyre bead<br />
over the top rim flange, starting at the valve area. Be careful not<br />
to damage the tyre beads by using excessive leverage.<br />
Remove the tube if fitted.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 29
7<br />
Remove the bottom bead over the top rim flange.<br />
Light Truck, Truck <strong>Tyre</strong>s - Multi-Piece Rims<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
Remove the valve core <strong>and</strong> completely deflate the tyre. This must<br />
always be done be<strong>for</strong>e removing a wheel from a vehicle or removing<br />
a tyre from a wheel. This applies to both tyres in a dual assembly.<br />
Run a piece of wire through the valve stem to ensure it is not<br />
plugged.<br />
Lay the assembly on the ground with the lock ring assembly facing<br />
upwards.<br />
Unseat the top facing bead with the appropriate tools or equipment.<br />
Follow the instructions supplied with equipment when using<br />
pneumatic, hydraulic, or mechanical equipment to break the bead<br />
seats.<br />
Use only approved tyre bead lubricant to assist with the bead<br />
breaking operation.<br />
Be careful to use the correct levers <strong>and</strong> not to distort loose flanges<br />
<strong>and</strong> lock rings when removing from the rim.<br />
Push the valve stem inside the rim where possible.<br />
Turn the wheel assembly over <strong>and</strong> unseat the tyre bead.<br />
Remove tyre away from rim.<br />
Demounting Off the Vehicle<br />
1<br />
Remove any water ballast or air from the tyre. Remove the valve<br />
core <strong>and</strong> completely deflate the tyre. Lay the assembly on the floor<br />
with the narrow ledge at the bottom.<br />
Remove the valve core.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 30
2<br />
Drive a bead unseating tool between the tyre bead <strong>and</strong> rim flange,<br />
being careful not to damage the tyre bead area. After the bead has<br />
been released completely around the tyre, turn the tyre <strong>and</strong> rim<br />
over <strong>and</strong> repeat the bead unseating procedure with the narrow<br />
ledge up.<br />
Unseat the bead.<br />
3<br />
With the narrow ledge on top, thoroughly lubricate the rim flange<br />
<strong>and</strong> tyre bead area with an approved tyre lubricant or a thin<br />
solution of vegetable oil soap in water. (Never use antifreeze,<br />
silicones or petroleum-based lubricants.)<br />
Lubricate the rim<br />
flange <strong>and</strong> tyre bead<br />
area.<br />
4<br />
Force the part of the bead that is directly across from the valve<br />
into the well. Starting at the valve, pry the top bead over the rim<br />
flange using two 18-inch-long tyre levers or the tyre mounting/<br />
demounting tool. Continue by taking small bites to avoid damage to<br />
the bead until the top bead is completely over the rim flange.<br />
Pry the bead over the<br />
rim flange.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 31
5<br />
6<br />
Bring the assembly to an upright position <strong>and</strong> pull the tube out of<br />
the tyre (if it is tubed). If only the tube requires repair or replacement,<br />
this can be removed, repaired, <strong>and</strong> replaced in the tyre<br />
without removing the tyre completely from the rim.<br />
Thoroughly inspect the inside of the casing <strong>for</strong> damage or other<br />
<strong>for</strong>eign material. Remove any remaining fluid from inside the tyre.<br />
Break the second bead.<br />
Lift the bead over the<br />
flange.<br />
7<br />
8<br />
9<br />
10<br />
To completely remove the tyre from the rim, turn assembly over so<br />
the narrow ledge is down.<br />
Lubricate the second tyre bead <strong>and</strong> rim flange. Be sure the one<br />
side of the bead still on the rim is in the rim well <strong>and</strong> insert the<br />
tyre levers or the mounting demounting tool under the opposite<br />
side of the bead.<br />
Work the rim slowly out of the tyre by taking small bites alternately<br />
using both tyre levers. Alternatively, use the mounting/<br />
demounting tool to lift the bead over the flange.<br />
Remove the tyre from the wheel.<br />
Remove the tyre.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 32
Demounting On The Vehicle<br />
(Some steps <strong>for</strong> the following procedure may require two persons on larger<br />
size tyres)<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
Jack up the vehicle, then deflate the tyre by removing the valve<br />
core housing. If necessary position the tyre <strong>for</strong> emptying any fluid<br />
fill from the tyre. For tube-type tyres, remove the rim nut <strong>and</strong> push<br />
the valve through the valve hole.<br />
After the tyre is completely deflated, place a hydraulic “bead<br />
unseating” tool between the tyre bead <strong>and</strong> rim flange <strong>and</strong> <strong>for</strong>ce the<br />
bead off the bead seat. Be careful not to damage the tyre’s bead<br />
area. The beads should be unseated on both sides of the rim.<br />
Thoroughly lubricate the tyre bead area <strong>and</strong> rim flange with an<br />
approved tyre mounting lubricant or a thin solution of vegetable oil<br />
soap in water. (Never use antifreeze, silicones or petroleum-base<br />
lubricants because this will damage the tyre.)<br />
Force the part of the bead that is directly across from the valve<br />
into the well. Starting at the valve, pry the top bead over the rim<br />
flange using two 18-inch long tyre levers or the tyre mounting/<br />
demounting tool. Continue by taking small bites to avoid damage to<br />
the bead until the top bead is completely over the rim flange.<br />
Bring the assembly to an upright position <strong>and</strong> pull the tube out of<br />
the tyre (if it is tubed). If only the tube requires repair or replacement,<br />
this can be removed, repaired, <strong>and</strong> replaced in the tyre<br />
without removing the tyre completely from the rim.<br />
Thoroughly inspect the inside of the casing <strong>for</strong> damage or other<br />
<strong>for</strong>eign material. Remove any remaining fluid from inside the tyre.<br />
To completely remove the tyre from the rim, turn assembly over so<br />
the narrow ledge is down.<br />
Lubricate the second tyre bead <strong>and</strong> rim flange. Be sure the one<br />
side of the bead still on the rim is in the rim well <strong>and</strong> insert the<br />
tyre levers or the mounting demounting tool under the opposite<br />
side of the bead.<br />
Work the rim slowly out of the tyre by taking small bites alternately<br />
using both tyre levers. Alternatively use the mounting/<br />
demounting tool to lift the bead over the flange.<br />
Remove the tyre from the wheel.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 33
7: Repairing <strong>Tyre</strong>s<br />
Using a tyre changing<br />
machine.<br />
An electrohydraulic<br />
semi-automatic tyre<br />
changer to demount<br />
<strong>and</strong> mount truck, bus,<br />
tractor <strong>and</strong> earth<br />
moving equipment<br />
tyres.<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
11<br />
12<br />
<strong>Tyre</strong>s which contain a substance additional to compressed air must<br />
be treated with caution. Flammable examples are gas propellant<br />
used to pressurise latex <strong>for</strong> emergency puncture repair, or methylated<br />
spirits used as antifreeze in tractor tyres.<br />
<strong>Tyre</strong> sealants <strong>and</strong> repair materials are to be used strictly according<br />
to manufacturers’ instructions. <strong>Tyre</strong> sealants used to seal tyres<br />
against air loss require special steps during examination <strong>for</strong> punctures.<br />
Clean <strong>and</strong> carefully examine all flanges, locking rims <strong>and</strong> rim<br />
gutters. Reject any that are damaged, distorted, cracked or broken.<br />
They must not be reused under any circumstances.<br />
Don’t interchange rim parts. Although they may look alike, variance<br />
between rims of different types makes part-mixing dangerous.<br />
Side rings, flanges <strong>and</strong> lock rings of different types may appear to<br />
be correctly seated but actually have wide gaps which make them<br />
dangerous. Check markings.<br />
With tyres which have been run at low pressure, look especially <strong>for</strong><br />
sidewall damage. Reject tyres with dark lines or broken steel cords.<br />
Check that the tyre is in sound condition, both inside <strong>and</strong> outside,<br />
<strong>and</strong> be sure to use only the correct size <strong>and</strong> type of tube, flap,<br />
flange <strong>and</strong> locking ring.<br />
Always use an approved tyre bead lubricant when fitting tyres.<br />
After assembling a wheel <strong>and</strong> tyre, check the positioning of loose<br />
flanges <strong>and</strong> the locking ring. Don’t inflate until they are right.<br />
Be<strong>for</strong>e inflating, be sure that you know the correct pressure <strong>for</strong> the<br />
size <strong>and</strong> ply rating of the tyre. Don’t guess.<br />
Use a cage guard, or if a cage guard is not available, use a suitable<br />
restraining device.<br />
Wear suitable eye protection be<strong>for</strong>e starting assembly. This is<br />
important!<br />
If you have any doubts about what to do, or about what you have<br />
done, ask your supervisor, or check the appropriate manual or wall<br />
chart be<strong>for</strong>e inflating.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 34
Zipper Hazard<br />
The zipper rupture is not uncommon <strong>and</strong> potentially is one of the most<br />
dangerous that tyre service persons are frequently exposed to. A zipper is<br />
the name given to the bursting of a radial truck tyre sidewall circumferentially<br />
in the mid to upper sidewall area.<br />
A tyre with a zippered side wall.<br />
The steel-belted radial truck tyre has a carcass which consists of one single<br />
body ply. This ply is made up of steel wires or cables, each consisting of a<br />
number of filaments wound to provide a flexible yet strong sidewall. Steelbelted<br />
radial truck tyres, like other tyres, are designed to deflect within an<br />
optimum range when loads, pressures <strong>and</strong> road surface variations are<br />
imposed. When, however, a steel-belted radial truck tyre is run underinflated,<br />
the deflection is significantly increased, concentrating stress in one<br />
particular area of the sidewall. This has the effect of causing the body ply<br />
wires or cables in the sidewall to bend at angles far greater than they are<br />
designed <strong>for</strong>, or capable of, <strong>and</strong> they begin to break.<br />
Eventually, only a small number of wires or filaments remain intact within<br />
the area. This is when the zipper is at its most dangerous state.<br />
In this state, either continued deflection or an increase in pressure will<br />
cause the tyre to explode.<br />
KEY POINT<br />
When a zipper <strong>for</strong>ms, during inflation, the weakened sidewall will start to tear<br />
at the point of weakness, <strong>and</strong> burst with a long narrow opening. Wire <strong>and</strong><br />
rubber shrapnel will leave the tear driven by escaping compressed air. When<br />
the zipper occurs at higher pressures, whole tyre <strong>and</strong> wheel assemblies can<br />
be thrown in any direction as the sidewall explodes.<br />
A truck has been blown off its jack, <strong>and</strong> tyre servicemen blown across the<br />
fitting bay. Injuries include penetration by wire shrapnel, deep into the arm of<br />
one victim, <strong>and</strong> impact of thrown wheel assemblies with injuries requiring<br />
hospital treatment. The zipper effect has already claimed the life of one tyre<br />
worker in New Zeal<strong>and</strong>.<br />
Identifying the Hazard<br />
So how do we recognise tyres with zipper symptoms? Symptoms are difficult<br />
to detect, in fact, most people who experience zippers said that there were<br />
no marks or indications on the inside or outside of the tyre.<br />
• Most tyres were known to have been punctured or flat be<strong>for</strong>e the<br />
u<strong>nz</strong>ipping occurred.<br />
• A creaking/ripping noise occurred just be<strong>for</strong>e u<strong>nz</strong>ipping occurred.<br />
• Bulging was often not evident be<strong>for</strong>e u<strong>nz</strong>ipping occurred.<br />
• Pressures at which the zipper occurred ranged from as low as 20<br />
psi up to 100 psi, with most zippers occurring between 60 - 80 psi.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 35
Any tyre which has a darkened line on the liner at the shoulder area, any<br />
tyre which creaks or clicks when flexing the sidewall, any tyre which shows<br />
wavy or run flat type sidewall marks, any tyre which has been known to<br />
have had a puncture or been run underinflated or overloaded, is a risk. If<br />
you are at all suspicious about a tyre, then get a second opinion be<strong>for</strong>e<br />
mounting it. If in doubt, scrap it (with the customer’s permission of course).<br />
Inspection<br />
Often, potential zipper tyres will exhibit clues which singly or together may<br />
indicate that the tyre has been run under-inflated <strong>and</strong> potentially may<br />
u<strong>nz</strong>ip. Inspect carefully <strong>for</strong> the following:<br />
• Fleet-check marking on the tyre showing a low pressure or flat tyre.<br />
• Bulges, distortion or buckling of the tyre sidewall.<br />
• Discolouration, wave marks, wrinkling, or crease marks on the<br />
inner liner.<br />
• Protruding cords or wire filaments.<br />
• Any penetration through the liner <strong>and</strong> indications of under-inflated<br />
use.<br />
• Any under-inflated use.<br />
• Any sidewall areas exhibiting soft or weak areas.<br />
Checking a side wall.<br />
• Any creaking, clicking, or popping noise.<br />
Be aware, however, that tyres may u<strong>nz</strong>ip without any of the above indications<br />
being present <strong>and</strong> at any pressure. <strong>Tyre</strong>s exhibiting any of the above<br />
indications must not be inflated. Such tyres should have a warning tag<br />
affixed or be rendered unusable by cutting the sidewall (with the customer’s<br />
permission of course).<br />
Deflating a Zipper<br />
Should a tyre exhibit bulging, distortion, creaking or clicking noises, immediately:<br />
Stop inflation.<br />
1<br />
2<br />
Release the hose from the air supply.<br />
Do not attempt to remove the hose from the valve stem until fully deflated.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 36
KEY POINT<br />
Not all radial truck tyres with potential to zipper exhibit any of the above<br />
clues. Accordingly, all radial truck tyres should be treated as potential<br />
zippers.<br />
Follow these basics:<br />
• Always inflate all truck tyres in a safety cage.<br />
• Remove tools away from the inflation area.<br />
• Remove the valve core <strong>for</strong> the first inflation.<br />
• Use a minimum 2-metre long hose with clip-on chuck <strong>and</strong> quick<br />
release device at both ends.<br />
• Wear face masks <strong>and</strong> overalls with sleeves down.<br />
• Keep earmuffs off during inflation.<br />
• Turn radio down.<br />
• Listen carefully <strong>for</strong> any creaking, clicking noises during inflation.<br />
• Check the sidewalls externally at 20 kPa or 3 psi <strong>for</strong> any bulges or<br />
distortion.<br />
• Stay out of the trajectory area.<br />
Shaded areas are probable trajectories <strong>for</strong> wheel parts should tyres explode.<br />
Roadside or Off-Site Servicing<br />
Often servicing must be per<strong>for</strong>med away from the tyre service bay or any<br />
nearby safety cage. In such instances it is important that the tyre <strong>and</strong> wheel<br />
assembly is restrained during inflation <strong>and</strong> to keep well clear of the trajectory.<br />
Restraint may take any one of these <strong>for</strong>ms:<br />
• Use the fold-down safety cage if one is fitted to the service vehicle.<br />
• Restrain the tyre-wheel by lowering a tail-lift, if one is fitted. Be<br />
aware that the tailgate may lift rapidly during an explosion.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 37
• Slide the tyre wheel assembly under the service vehicle.<br />
• If none of the above are practicable, ensure that a substantial<br />
vehicle is between the tyre <strong>and</strong> people in the area.<br />
• Bolt the tyre wheel assembly to the vehicle be<strong>for</strong>e inflating.<br />
• Keep out of the trajectory path.<br />
<strong>Safety</strong> Rules <strong>for</strong> Road Side Servicing<br />
Wear high-visibility vests.<br />
1<br />
<strong>Tyre</strong> Sealants<br />
2<br />
3<br />
4<br />
5<br />
If practicable, drive on to a lay by.<br />
If it is not practicable to drive on to a lay by, pull off the road.<br />
If it is not practicable to pull off the road, park the vehicle as far<br />
left as possible, <strong>and</strong> put out warning cones <strong>and</strong> triangles.<br />
If it is not possible to work safely because the vehicle is in an<br />
unsafe position, call the police to manage traffic at the site.<br />
<strong>Tyre</strong> sealants is the name <strong>for</strong> three groups of products.<br />
On-road tyre sealants<br />
Photo: Using a<br />
tyre sealant<br />
These are intended to help retain air at the correct pressure, <strong>and</strong> must be<br />
used according to the manufacturer’s specifications. A tyre sealant <strong>for</strong> onroad<br />
use must be able to maintain the balance of the tyre in highway conditions<br />
of high speed <strong>and</strong> raised temperature, <strong>and</strong> cannot be safely replaced by<br />
sealant intended <strong>for</strong> off-road use.<br />
When adding sealant to tyres, the tyre profile must be maintained, without<br />
the weight of the vehicle being allowed to flatten the tyre. Failure to follow<br />
this instruction may result in the tyre becoming damaged. Ensure when<br />
using tyre sealants that you adhere strictly to manufacturers’ dosage instructions.<br />
When using a tyre<br />
sealant, always follow<br />
the manufacturer’s<br />
instructions.<br />
<strong>Tyre</strong>s treated with on-road tyre sealant which lose air should have a repair<br />
done in accordance with NZS 5423:1996 Specification <strong>for</strong> repairing <strong>and</strong><br />
retreading car, truck <strong>and</strong> bus tyres or the LTSA Wheels <strong>and</strong> <strong>Tyre</strong>s Rule.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 38
KEY POINT<br />
When adding sealant to vehicle tyres, the tyre profile must be maintained.<br />
The supplier’s instructions must be strictly followed.<br />
<strong>Tyre</strong> sealants <strong>for</strong> off-road tyres<br />
<strong>Tyre</strong> sealants <strong>for</strong> off-road tyres are <strong>for</strong> use at low pressure <strong>and</strong> low speed.<br />
They are used to repair punctures in the tread, but not in the shoulder or<br />
sidewalls of tyres.<br />
KEY POINT<br />
<strong>Tyre</strong> sealants <strong>for</strong> off-road tyres are <strong>for</strong> use at low speed.<br />
Aerosol tyre sealants <strong>for</strong> temporary repairs<br />
Temporary puncture repair tyre sealants <strong>for</strong> puncture repairs are blown<br />
from an aerosol can. Manufacturers’ instructions must be followed. Their<br />
main market appears to be car drivers who want inflation of a flat tyre to<br />
enable continuing their journey without a wheel change.<br />
Temporary puncture<br />
repair tyre sealants are<br />
blown from an aerosol<br />
can.<br />
Some tyre sealants <strong>for</strong> temporary repairs contain propane. The first fill of<br />
propane in most cases will put the concentration of propane in the tyre<br />
above the upper explosive limit. Re-inflation with air may reduce the concentration<br />
of propane to <strong>for</strong>m an explosive mixture of air <strong>and</strong> propane in the<br />
tyre. The tyre can then be compared with a bomb. An ignition source, such<br />
as a reamer against steel wires in a radial tyre, may cause an explosion.<br />
<strong>Tyre</strong> sealants <strong>for</strong> temporary repairs which use latex are nonflammable.<br />
<strong>Tyre</strong> repairers should find out which tyre sealant was used <strong>for</strong> any temporary<br />
repair.<br />
KEY POINTS<br />
Check to see whether this tyre has been treated with an aerosol can sealant.<br />
<strong>Tyre</strong>s must be removed from the wheel <strong>for</strong> repair.<br />
BEWARE OF PUNCTURED TYRES WHICH ARE STILL INFLATED.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 39
8: <strong>Tyre</strong> Mounting<br />
<strong>Safety</strong> Precautions<br />
WARNING<br />
There is a danger of serious injury or death if a tyre of one bead diameter is<br />
installed on a rim or wheel of a different rim diameter.<br />
Always replace a tyre with another tyre of exactly the same bead diameter<br />
designation <strong>and</strong> suffix letters. For example:<br />
• A 16-inch diameter tyre goes on a 16-inch diameter rim. Never<br />
mount a 16-inch diameter tyre on a 16.1-inch diameter or 16.5-inch<br />
diameter rim.<br />
• A 16.1-inch diameter tyre goes on a 16.1-inch diameter rim. Never<br />
mount a 16.1-inch diameter tyre on a 16-inch diameter or 16.5-inch<br />
diameter rim.<br />
• A 16.5-inch diameter tyre goes on a 16.5-inch diameter rim. Never<br />
mount a 16.5-inch diameter tyre on a 16-inch diameter or 16.1-inch<br />
diameter rim.<br />
For the same reason:<br />
• Never mount a 26-inch diameter tyre on a 26.5-inch diameter rim.<br />
• Never mount a 30-inch diameter tyre on a 30.5-inch diameter rim.<br />
While it is possible to pass a 16-inch diameter tyre over the lip or flange of<br />
a 16.1-inch diameter or 16.5-inch diameter rim, it cannot be inflated enough<br />
to position itself against the rim flange. If an attempt is made to seat the<br />
tyre bead by inflating, the tyre bead will break with explosive <strong>for</strong>ce <strong>and</strong><br />
could cause serious injury or death.<br />
To Determine Compatible Rim Width <strong>for</strong> <strong>Tyre</strong> Sizes<br />
Measurement of rim<br />
width <strong>and</strong> diameter.<br />
1<br />
2<br />
3<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 40<br />
Determine the vehicle’s actual rim width by measuring, in inches,<br />
the distance between the vertical bead flanges as shown. A simple<br />
ruler or yardstick may be used, as rims are manufactured in half<br />
inch increments of width.<br />
Check the tyre that came off the rim. Look on the rim <strong>for</strong> tyre size.<br />
If you can’t read rim markings, check with the vehicle manufacturer<br />
or have a qualified person read the rim.<br />
Rims <strong>for</strong> specialised applications require special tyres. The size<br />
code of the rim must be checked <strong>for</strong> compatibility.
Mounting <strong>Tyre</strong>s<br />
Compressed air lines must have a press button or similar type of h<strong>and</strong><br />
control. There must be at least 2 metres of air line between the h<strong>and</strong> control<br />
<strong>and</strong> the chuck which clips on to the tyre valve. This is essential <strong>for</strong> your<br />
safety: it keeps you out of the most dangerous area should anything go<br />
wrong. Follow these steps <strong>for</strong> your own safety:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
With a suitable lamp, examine the tyre wall <strong>for</strong> any bulging due to<br />
damage. Zippering walls may show signs of bulging. Reject any tyre<br />
in which zippering is starting to occur. Turn down the workshop<br />
radio <strong>and</strong> inflate the tyre, listening <strong>for</strong> popping noises which signal<br />
ripping of cords in the tyre wall. Zippering is most likely in tyres<br />
which have been run at low pressure. Ripping cords signal the start<br />
of a zipper.<br />
Inflate to about 20 kPa (3 psi), but definitely not above 35 kPa (5<br />
psi). Then check that the tyre is properly centred on the rim <strong>and</strong><br />
that flanges <strong>and</strong> locking rings are correctly seated.<br />
Remove the valve core <strong>and</strong> allow the tyre to deflate fully. Now,<br />
place the tyre/wheel assembly into a safety cage or suitable restraining<br />
device, be<strong>for</strong>e inflating using a clip on chuck. Passenger<br />
tyres fitted on passenger well-base rims may be inflated without a<br />
safety cage.<br />
Inflate to full pressure, st<strong>and</strong>ing away from the tyre, but still<br />
listening <strong>for</strong> popping caused by zippering. Any zippering tyre shall<br />
be rejected. After inflation, release the air pressure <strong>and</strong> allow the<br />
tyre to deflate. You can now replace the valve core <strong>and</strong> inflate fully.<br />
This is the stage where most accidents <strong>and</strong> the most serious injuries<br />
occur. In every accident notified to OSH, the dead or injured<br />
person has not correctly used a suitable cage guard or restraining<br />
device. Be sure, by a thorough examination, that it is safe to proceed<br />
to full inflation.<br />
ACCIDENT CASE<br />
Air hose left unattended<br />
A tyre fitter left an open-ended air line attached to the valve of a<br />
tractor tyre while he went to answer the telephone. The conversation<br />
took longer than expected, <strong>and</strong> when he returned he realised the tyre<br />
was dangerously over-inflated. As he removed the chuck from the<br />
valve, the tyre exploded <strong>and</strong> he was thrown against the ceiling <strong>and</strong><br />
killed instantly.<br />
6<br />
While inflating on the vehicle, use an in-line gauge <strong>and</strong> control<br />
device with at least 2 metres of hose between the control device<br />
<strong>and</strong> clip-on chuck so that you can st<strong>and</strong> well clear.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 41
7<br />
8<br />
9<br />
Attend to the air line the whole time that the tyre is inflating.<br />
Never leave an un-monitored air line attached to a valve.<br />
Never hammer on an inflated or partially inflated tyre/rim assembly.<br />
It could fly apart <strong>and</strong> kill or seriously injure you or someone<br />
else.<br />
After running the vehicle <strong>for</strong> a short distance, wheel nuts should be<br />
checked <strong>for</strong> tightness. Parts will seat naturally <strong>and</strong> torque on nuts<br />
will drop, requiring them to be tightened to the correct specifications.<br />
This is essential; in the worst case the wheel will fall off.<br />
Mounting of Common Assemblies <strong>Tyre</strong>s<br />
Car, Van <strong>and</strong> Front Tractor <strong>Tyre</strong>s — Well-Base Rims<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
11<br />
Check that rim bead seats <strong>and</strong> flanges are in good condition <strong>and</strong><br />
not damaged or distorted.<br />
Be sure the tyre casing is undamaged <strong>and</strong> that there is no <strong>for</strong>eign<br />
matter left inside the tyre.<br />
Place the rim on the fitting machine or floor with the narrow rim<br />
ledge facing upwards.<br />
Check to see if the tyre has to be fitted a certain direction.<br />
Lubricate both tyre beads with approved tyre lubricant.<br />
Position bottom tyre bead over top rim flange, working tyre bead<br />
into the rim well.<br />
Insert tube if tube type.<br />
Position top tyre bead over top rim flange, working tyre bead into<br />
the rim well.<br />
Be<strong>for</strong>e inflating, be sure of the correct pressure <strong>for</strong> the size <strong>and</strong> ply<br />
rating of the tyre. Never exceed the maximum pressure shown on<br />
page 56 of this booklet.<br />
Inflate to 35 kPa (5 psi) only, then check that the tyre is properly<br />
centred on the rim. Don’t check the seating of the bead by st<strong>and</strong>ing<br />
over the wheel, but from one side.<br />
In the case of larger tractor tyres, you should put the assembly into<br />
a safety cage or other suitable restraining device. If a safety cage is<br />
impracticable to use, <strong>for</strong> example in the middle of a paddock with a<br />
large tractor tyre, it should be possible to inflate the tyre with a<br />
vehicle between the tyre <strong>and</strong> the service person. If you don’t, <strong>and</strong><br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 42
12<br />
the assembly comes apart during inflation, you are likely to be<br />
killed or seriously injured.<br />
If the tyre beads have not seated correctly at the recommended<br />
pressure, STOP! Deflate the tyre. Free the beads <strong>and</strong> relubricate<br />
them. Reinflate the tyre.<br />
ACCIDENT CASE<br />
<strong>Tyre</strong> bead not seated at low pressure<br />
A mechanic was inflating a tractor tyre he had just fitted to the wheel<br />
rim. He had difficulty getting the bead to seat against the rim <strong>and</strong><br />
asked an experienced workmate to help him. The tyre was marked<br />
WARNING: NEVER EXCEED 35 PSI WHEN SEATING BEAD. As the man was<br />
leaning over to examine it, the tube burst <strong>and</strong> the tyre was <strong>for</strong>ced over<br />
the rim, throwing him a metre in the air. He was struck by the rim <strong>and</strong><br />
died from his injuries. There was a suitable tyre cage metres away. The<br />
pressure gauge fitted to the air line was not working <strong>and</strong> it was assumed<br />
later that the tyre may have been inflated to a pressure of 80<br />
psi.<br />
Light Truck, Truck <strong>Tyre</strong>s — Multi-Piece Rims<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
Be<strong>for</strong>e you start, be sure that the flanges <strong>and</strong> locking rings are the<br />
right size <strong>and</strong> are in good condition. Check <strong>for</strong> any damage, distortion<br />
or cracks with the rim, flange or lockring. Discard damaged<br />
components. In most cases don’t try to repair or modify them — it<br />
could kill you or those using the vehicle. Wheel repair is a specialised<br />
skill <strong>and</strong> advice must be sought when there is a doubt.<br />
If the rim is a 4-piece flat-base type, ensure that the inner flange<br />
ring has been fitted.<br />
Check that the inside of the tyre is clean from <strong>for</strong>eign matter.<br />
Insert the inner tube <strong>and</strong> flap. Partially inflate the tube to con<strong>for</strong>m<br />
to the tyre shape. Check the tube has not creased or pinched.<br />
Attach a valve retrieval tool to the valve stem <strong>and</strong> thread the tool<br />
through the valve hole.<br />
Lubricate both tyre beads with approved tyre lubricant.<br />
Place the rim on the ground with the lock ring side facing upwards.<br />
Mount the tyre over the rim locating the valve retrieval tool<br />
stem through the rim valve hole.<br />
Fit the flange <strong>and</strong> lock ring into the correct seating position. DO<br />
NOT use excessive <strong>for</strong>ce to fit the lock ring.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 43
8<br />
9<br />
10<br />
11<br />
Inflate to no more than 35 kPa (5 psi) <strong>and</strong> check that the tyre is<br />
properly centred on the rim. Check that the loose flanges <strong>and</strong> lock<br />
rings are correctly seated.<br />
Don’t st<strong>and</strong> over the wheel. Check the seating of the parts from the<br />
side. Never attempt to correct the seating of the side <strong>and</strong> locking<br />
rings by hammering, or by <strong>for</strong>cing the components while the tyre is<br />
pressurised.<br />
The assembly must be kept in the restraining device while it is<br />
inflated to the recommended pressure <strong>and</strong> the tyre, rim <strong>and</strong> rings<br />
are seen to be properly seated <strong>and</strong> locked. If they are not, then<br />
deflate the tyre. The assembly may then be removed from the<br />
restraining device <strong>and</strong> the components relubricated <strong>and</strong> repositioned.<br />
You should again inflate it to no more than 35 kPa (5 psi),<br />
check it <strong>and</strong> then replace it in the restraining device <strong>for</strong> inflation<br />
to the recommended pressure.<br />
Multi-piece rim wheels also require special care because of their<br />
weight. You should be careful that loose flanges <strong>and</strong> locking rings<br />
do not drop on your fingers when lifting. Remember when rolling,<br />
they are liable to veer off suddenly. Also the loose flange or locking<br />
ring may move violently from one side of the rim to the other, so<br />
keep your fingers clear.<br />
Mounting off the Vehicle<br />
1<br />
Lay the rim on the floor with the narrow<br />
ledge on the top. Thoroughly lubricate the<br />
tyre bead area <strong>and</strong> rim flange with an<br />
approved tyre mounting lubricant or a thin<br />
solution of vegetable oil soap in water.<br />
(Never use antifreeze, silicones or petroleumbase<br />
lubricants because this will damage the<br />
tyre.)<br />
Push the bottom bead<br />
over the rim flange.<br />
2<br />
3<br />
Push the bottom bead over the rim flange as<br />
far as possible.<br />
Use 18-inch tyre levers or the tyre mounting/demounting tool to<br />
work the first tyre bead completely over the rim flange, taking<br />
small bites <strong>and</strong> being careful not to damage the bead.<br />
Work the first tyre bead<br />
over the rim flange.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 44
Use tyre levers to<br />
lever the top bead<br />
over the rim flange<br />
<strong>and</strong> down into the rim<br />
well.<br />
Place tyre/rim/wheel<br />
on a safety cage or<br />
other restraining<br />
device.<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
If using a tubeless tyre, place the valve through the hole in the rim.<br />
Starting opposite the valve, use tyre levers to lever the top bead<br />
over the rim flange <strong>and</strong> down into the rim well. Be careful to avoid<br />
pinching the tube with tyre levers. Locking pliers may be used to<br />
keep your place. When the bead is well started, lubricate the<br />
remaining unmounted portion of the tyre bead <strong>and</strong> rim flange.<br />
Taking small bites, spoon the tyre bead over the rim flange until<br />
the final section drops over at the valve.<br />
Thoroughly lubricate the tyre bead area <strong>and</strong> rim bead seats on both<br />
sides of the tyre.<br />
Centring the tyre on the rim is extremely important to prevent<br />
broken beads. Use an extension hose with an in-line air gauge <strong>and</strong><br />
clip-on chuck.<br />
Place tyre/rim/wheel on a safety cage or other restraining device.<br />
Wear face protection. Inflate the tyre (with the valve core removed)<br />
to seat the beads. Do not exceed 245 kPa (35 psi). It is essential <strong>for</strong><br />
the operator to st<strong>and</strong> clear of the tyre. Check to see that both<br />
beads are seated all the way around the tyre. If the tyre is tubetype,<br />
completely deflate (to allow repositioning of the tube) by<br />
removing the valve core housing. For tubeless tyres, mounting<br />
depends on how well the shape of the tyre has been maintained. If<br />
the beads are in or near their moulded position, they can be seated<br />
by inflating the tyre, through the valve spud. Where the beads have<br />
been squeezed together, the use of an inflator ring (either horizontally<br />
or vertically) will be required to provide a seal between the<br />
tyre bead <strong>and</strong> rim.<br />
Check the tyre <strong>for</strong> evidence of potential zipper rupture.<br />
Re-insert the valve core <strong>and</strong> re-inflate the tyre to the vehicle manufacturer’s<br />
recommended operating pressure. Remove from the<br />
safety cage.<br />
Mounting on the Vehicle — Agricultural<br />
1<br />
2<br />
Thoroughly lubricate the tyre bead area <strong>and</strong> rim flange with an<br />
approved tyre mounting lubricant or a thin solution of vegetable oil<br />
soap in water. (Never use antifreeze, silicones or petroleum-base<br />
lubricants because this will damage the tyre.)<br />
Be<strong>for</strong>e placing tyre on rim, be sure valve hole of rim is at bottom<br />
of wheel. To put the tyre on the wheel, place the inner bead over<br />
the flange at the top. Be sure the bead is not hung up on the bead<br />
seat, but that the bead is guided into the rim well, while the tyre<br />
levers <strong>and</strong>/or rubber mallet are used to work the first bead over<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 45
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
the rim. With the first bead on the rim, pull the tyre toward the<br />
outside of the rim as far as possible to make room <strong>for</strong> the tube.<br />
Be<strong>for</strong>e inserting a tube in a tube-type tyre, be sure the valve is at<br />
the bottom of the wheel. Align the stem with the valve hole <strong>and</strong><br />
place the tube in the tyre, starting at the bottom. Place the valve in<br />
the valve hole <strong>and</strong> screw the rim nut in place. Be sure that the<br />
tube is well inside the rim be<strong>for</strong>e proceeding to the next step.<br />
Relubricate the tyre beads <strong>and</strong> rim flange. In tube-type tyres the<br />
tube should be partially inflated <strong>and</strong> base area that contacts the<br />
rim should be lubricated to prevent localised stretching.<br />
Starting at the top, use the tyre levers to lift the outer bead up <strong>and</strong><br />
over the rim flange. then down into the rim well. Be careful not to<br />
pinch the tube in this operation.<br />
After getting the first section of the outer bead into the rim well,<br />
place one h<strong>and</strong> against that section to hold it <strong>and</strong> then pry the<br />
remainder of the bead over the flange with the tyre lever in the<br />
other h<strong>and</strong>.<br />
With the valve stem at the bottom, lower the jack until the tyre is<br />
centred on the rim. Centring of the tyre <strong>and</strong> rim assembly is<br />
extremely important to prevent broken beads. Wear face protection.<br />
Using an extension hose with an in-line air gauge <strong>and</strong> clip-on chuck<br />
(with valve core removed), inflate the tyre to seat the beads. Do not<br />
exceed 245 kPa (35 psi). It is essential <strong>for</strong> the operator to st<strong>and</strong><br />
clear of the tyre. Check to see that both beads are seated all the<br />
way around the tyre. For tubeless tyres, mounting depends on how<br />
well the shape of the tyre has been maintained. If the beads are in<br />
or near their moulded position, they can be seated by inflating the<br />
tyre, through the valve spud. Where the beads have been squeezed<br />
together, the use of an inflator ring (either horizontally or vertically)<br />
will be required to provide a seal between the tyre bead <strong>and</strong><br />
rim.<br />
Raise the vehicle <strong>and</strong> rotate wheel assembly to have the valve at<br />
the top. If the tyre is tube-type, completely deflate by removing the<br />
valve core housing. Re-insert the valve core <strong>and</strong> re-inflate the tyre<br />
to the recommended operating pressure.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 46
9: Rim <strong>and</strong> Wheel<br />
Types<br />
Drop Centre or Well Base Rim<br />
Flat base rim (rear)<br />
<strong>and</strong> drop centre rim<br />
(front).<br />
Drop centre rim.<br />
The drop centre rim is of one-piece construction with a 5 0 to 15 0 taper in<br />
the bead seat on both sides. This is the rim used <strong>for</strong> tubeless tyres <strong>and</strong> it<br />
can be mounted on medium <strong>and</strong> heavy trucks, commercial trailers <strong>and</strong><br />
buses.<br />
Flat Base Rims<br />
Two-piece <strong>and</strong> three-piece flat base rims.<br />
The flat base rim is made in either two- or three-piece construction <strong>and</strong> is<br />
designed <strong>for</strong> use with tube-type tyres. This is the rim commonly used on<br />
medium <strong>and</strong> heavy trucks, trailers <strong>and</strong> buses.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 47
Wide Base One-Piece Rim<br />
Wide-base rim.<br />
Wide-base rim.<br />
The wide-base rim is also of one-piece construction, with a 5 0 or 15 0 taper in<br />
the bead seats. It is made <strong>for</strong> the super-single type of tyre, where one unit<br />
replaces dual tyres. They are used on light, medium <strong>and</strong> heavy trucks <strong>and</strong><br />
trailers. The rim is measured in width (W) <strong>and</strong> distance (D). The width is<br />
that dimension between the side flanges, while the diameter is measured<br />
from where the heel of the bead fits on the rim. It is absolutely imperative<br />
to use the right size rim <strong>for</strong> the tyre, <strong>and</strong> to use a rim that has the load<br />
rating to carry the tyre that is to be used. To be sure of this, always check<br />
the rim charts <strong>and</strong> load <strong>and</strong> inflation tables.<br />
Multi-Piece Rims<br />
Multi-piece rim.<br />
Multi-piece rim.<br />
A multi-piece rim is any rim with two or more parts, one of which is a<br />
locking ring that holds the inflated tyre on the rim by interlocking components.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 48
Semi-Drop Centre Rim<br />
The semi-drop centre rim is a two-piece rim with a base <strong>and</strong> side ring. The<br />
semi-drop centre design makes tyre mounting easier. These rims have a 5 0<br />
tapered bead seat on both sides <strong>and</strong> are used primarily <strong>for</strong> light trucks.<br />
Semi-drop centre rim.<br />
Divided Wheels<br />
Semi-drop centre rim.<br />
Divided wheels are those wheels in which the rim is in two halves which are<br />
bolted together. They are most often fitted to barrows, trolleys, implements,<br />
trucks or <strong>for</strong>klifts. However, there are some models of small Japanese cars<br />
<strong>and</strong> trucks with divided wheel rims. Particular care must be taken not to<br />
unfasten the rim clamping nuts while the tyre is still inflated. The clamping<br />
nuts are generally painted red, but this may not always be so.<br />
It is essential that every divided wheel has the tyre fully deflated <strong>and</strong> the valve<br />
removed be<strong>for</strong>e being removed from the vehicle. This is to prevent any chance<br />
of injury if the wrong nuts are undone.<br />
Several accidents reported to the Occupational <strong>Safety</strong> <strong>and</strong> <strong>Health</strong> Service of<br />
the Department of Labour have occurred because the wrong nuts were<br />
removed from inflated wheels, resulting in serious injury. Similarly, when<br />
inflating a tyre, you should be certain that the clamping nuts are fully<br />
tightened first.<br />
Divided wheel.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 49
10: Off-the-Vehicle<br />
Wheel Balancing<br />
A computerised off-thecar<br />
electronic wheel<br />
balancer.<br />
Ensure that the wheel<br />
has stopped rotating<br />
be<strong>for</strong>e attempting to<br />
h<strong>and</strong>le the wheel<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
11<br />
Ensure the balancing machine adapter is correctly <strong>and</strong> securely<br />
fixed to the tyre/wheel assembly. This is particularly important <strong>for</strong><br />
wire wheel adaptors.<br />
Carefully lift the tyre/wheel assembly on to the balancing machine<br />
spindle.<br />
Securely tighten the adapter collet.<br />
Check the machine be<strong>for</strong>e starting <strong>and</strong> ensure that there are no<br />
loose parts or tools on it.<br />
Remove any stones or extraneous materials from the tyre tread as<br />
they may fly out when the wheel is rotated. (The machine should<br />
be guarded to protect the operator).<br />
Don’t wear any loose clothing or jewellery that could be entangled<br />
when the wheel is rotated.<br />
Don’t allow anyone near the machine while the tyre/wheel assembly<br />
is rotating.<br />
Don’t touch the tyre/wheel assembly while it is rotating.<br />
Be sure that balance weights are securely clipped or stuck to the<br />
rim be<strong>for</strong>e checking any residual imbalance.<br />
If magnetic weights are used to determine static imbalance, remove<br />
them be<strong>for</strong>e starting the machine.<br />
Ensure that the wheel has stopped rotating be<strong>for</strong>e attempting to<br />
h<strong>and</strong>le the wheel or secure the adapter collet.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 50
11: On-the-Vehicle<br />
Wheel Balancing<br />
Excessive speed in a free-running, unloaded tyre can cause it to zipper or<br />
explode from extreme centrifugal <strong>for</strong>ce. If drive wheels must be balanced on<br />
the car, follow these precautions:<br />
Chock the wheels to prevent the vehicle from moving.<br />
1<br />
2<br />
3<br />
4<br />
Be sure the wheel is properly supported so that vibration will not<br />
dislodge the axle support <strong>and</strong> allow the vehicle to fall.<br />
Make sure people are clear of the areas in front of <strong>and</strong> behind the<br />
vehicle.<br />
On vehicles with a st<strong>and</strong>ard differential, put the transmission in<br />
top gear or drive <strong>and</strong> spin the wheel by gradual acceleration to a<br />
maximum of 65 km/h (40 m.p.h.) on the speedometer. Because of<br />
the differential, this is 130 km/h (80 m.p.h.) wheel speed with one<br />
wheel off the floor, or double the speedometer reading. Never rev<br />
the engine.<br />
ACCIDENT CASE<br />
Speeding tyre zippered apart<br />
A retread tyre had been fitted on the rim <strong>and</strong> then inflated to 90 psi,<br />
then placed on the outside of a dual wheel, which was rotating to<br />
centre the rim <strong>and</strong> tyre. To centre the wheel, the fitter arranged <strong>for</strong> the<br />
jacked wheel to be rotated under engine power to establish wheel<br />
centrality.<br />
While the person in the cab controlling the throttle kept indicated<br />
speed to 80 kph, with one wheel stopped on the ground, <strong>and</strong> one<br />
wheel turning under power, the turning wheel rotated at the equivalent<br />
of 160 kph. Differential operation always means that with one<br />
wheel stopped, while the other turns, the indicated speed will be one<br />
half turning speed. The tyre zippered, with part of the rubber hitting the<br />
fuel tank then the left side of the head <strong>and</strong> shoulder of the tyre fitter.<br />
He was taken to hospital, where he died of injuries.<br />
Possible effect <strong>for</strong> differential<br />
Vehicle manufacturers should be consulted as the differential side<br />
gears are spinning at a much higher speed than is the case in<br />
normal service <strong>and</strong> this may have warranty <strong>and</strong> safety implications.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 51
In normal circumstances, side gears rotate at a very slow speed to<br />
compensate <strong>for</strong> the slight speed difference between left <strong>and</strong> right<br />
wheels on an axle due to different tracks when going round corners,<br />
slightly different tyre diameters, etc.<br />
Four-wheel drive vehicles<br />
Some four-wheel drives are essentially two-wheel drive, normally<br />
rear, in normal on-road driving circumstances. Off-road, however,<br />
four-wheel drive can be selected <strong>and</strong> both front <strong>and</strong> rear axles now<br />
drive. Off-road the vehicle is driven at low speed as a centre differential<br />
is not fitted to allow <strong>for</strong> slightly different propeller shaft<br />
speeds, with wheel slippage on off-road terrain compensating. For<br />
on-road use, some are fitted with aftermarket free-wheeling hubs to<br />
disconnect the drive between the front wheels <strong>and</strong> front differential.<br />
This allows the vehicle to be driven on road without driving<br />
the front axle — reducing mechanical drag <strong>and</strong> fuel consumption.<br />
This arrangement, however, could lead to dangerous circumstances<br />
<strong>for</strong> the unwary, dependant on combinations selected <strong>and</strong> wheels<br />
raised, with vehicles literally being driven off jacks <strong>and</strong> chocks if<br />
the wrong combination is selected. The comments above relating to<br />
differential gears overreving also apply.<br />
Permanent four-wheel drive<br />
These vehicles have a centre differential which is intended to allow<br />
<strong>for</strong> slight speed differences between front <strong>and</strong> rear propeller shafts<br />
in normal driving. Stopping one propeller shaft completely <strong>and</strong><br />
sending all drive through the other vastly overrevs the centre diff<br />
side gears. In this circumstance, it is worse than the st<strong>and</strong>ard axle<br />
(refer comment above) as speed has not been reduced by<br />
crownwheel <strong>and</strong> pinion gearing, which is nominally about 3 to 1.<br />
These centre differentials can also be locked, creating a similar<br />
situation to the two-/four-wheel drive vehicle, which could also lead<br />
to dangerous circumstances <strong>for</strong> the unwary, with vehicles literally<br />
being driven off supports <strong>and</strong> chocks.<br />
5<br />
6<br />
The comments above relating to each axle differential also still<br />
apply.<br />
If vibration indicates a need <strong>for</strong> balancing, this will be indicated at<br />
speeds in the 50-65 km/h (30-40 m.p.h.) range on the speedometer,<br />
i.e. 100-130 km/h (60-80 m.p.h.) road speed. This is the maximum<br />
speed <strong>for</strong> dynamic balancing.<br />
If the vehicle has a limited slip differential, keep both wheels off<br />
the floor. Gradually accelerate to a maximum of 130 km/h (80<br />
m.p.h.) on the speedometer, which is also 130 km/in (80 m.p.h.)<br />
wheel speed.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 52
12: Balancing Truck<br />
Assemblies<br />
Take care when lifting<br />
truck assemblies on<br />
<strong>and</strong> off the balancing<br />
machine.<br />
The following procedures must be followed when h<strong>and</strong>ling truck assemblies:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
H<strong>and</strong>le truck assemblies carefully when lifting them on <strong>and</strong> off the<br />
balancing machine. They are often too heavy <strong>for</strong> one person to lift.<br />
Remove any stones or other loose material from the tread of the<br />
tyre. It could fly out when the machine is started.<br />
Secure the adapter plate to the balancing machine spindle. Place<br />
the lock pin in position.<br />
Roll the assembly on to the lifting frame <strong>and</strong> lift carefully.<br />
Secure the assembly to the wheel adapter plate while the weight is<br />
still fully supported by the lifting frame.<br />
Remove the lifting frame to a safe place where it is not an obstruction.<br />
Secure new balance weights on the rim flange.<br />
Place the balance arm mechanism in a safe place.<br />
Place the lock pin in position be<strong>for</strong>e attempting to loose any wheel<br />
adapter nuts.<br />
Support the weight of the assembly on the lifting frame while<br />
removing the wheel adapter nuts.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 53
13: Roadside <strong>Tyre</strong><br />
Repairs<br />
Always use road<br />
marker cones <strong>and</strong><br />
wear a high-visibility<br />
vest when carrying out<br />
roadside repairs.<br />
It is best if tyre repairs are carried out in a fully equipped workshop but<br />
there are times when they must be done at another work site or on the<br />
roadside. It is very important never to take chances with safety in such<br />
situations.<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
11<br />
If the work site does not have a suitable cage guard or restraining<br />
device, then one must be taken to the site or roadside. If a suitable<br />
cage guard or restraining device are not available, then less safe<br />
options are to place the wheel under the vehicle <strong>for</strong> inflation, or to<br />
bolt the wheel in place on the vehicle be<strong>for</strong>e inflation.<br />
Be<strong>for</strong>e you begin work, set up road marker cones round the roadside<br />
work area.<br />
Chock wheels on the opposite side of the vehicle be<strong>for</strong>e you place<br />
the jack in position.<br />
Regardless of how hard or firm the ground appears, put hardwood<br />
blocks under the jack. Use axle st<strong>and</strong>s where possible.<br />
Always wear your eye protection <strong>and</strong> a high-visibility safety vest if<br />
working on a roadside.<br />
St<strong>and</strong> clear when deflating. Ensure tyre is properly deflated by<br />
removing the valve core.<br />
St<strong>and</strong> to one side when you use hydraulic pressure demounting<br />
tools.<br />
Be particularly careful to clean all dirt <strong>and</strong> rust from lock rings<br />
<strong>and</strong> gutters, otherwise lock rings will not seat properly.<br />
Discard any components that are cracked, badly worn, damaged,<br />
bent, repaired or pitted from corrosion. When the condition of any<br />
component is in doubt replace it — even if this means a delay in<br />
obtaining new parts. Remember, if weakened parts give way during<br />
inflation, you are likely to be killed or seriously injured.<br />
When the inner wheel of a dual assembly has to be removed <strong>for</strong><br />
repair, then the outer wheel, where possible, should also be deflated<br />
be<strong>for</strong>e removal from the vehicle. Fatal accidents have occurred<br />
when this has not been done.<br />
Never introduce a flammable substance be<strong>for</strong>e, during or after<br />
mounting.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 54
12<br />
Don’t sit on, st<strong>and</strong> in front of, or st<strong>and</strong> over a tyre <strong>and</strong> rim assembly<br />
that is being inflated.<br />
KEY POINT<br />
<strong>Tyre</strong> service personnel required to change wheel assemblies by the roadside<br />
should take extra care by following the points set out in 2, 3, 4, 5, 6 <strong>and</strong> 9<br />
above.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 55
14: <strong>Tyre</strong> Inflation<br />
Pressures<br />
Never inflate above the pressures recommended by the tyre <strong>and</strong> wheel rim<br />
manufacturers. Maximum pressures may be stamped on the sidewalls of<br />
truck <strong>and</strong> light truck tyres. In practice, the following maximum pressures<br />
should not be exceeded:<br />
MAXIMUM INFLATION PRESSURES<br />
All car tyres 322 kPa (46 psi)<br />
All van tyres except 8-ply 420 kPa (60 psi)<br />
Light truck 560 kPa (80 psi)<br />
Motorcycle tyres 280 kPa (40 psi)<br />
Tractor, front 280 kPa (40 psi)<br />
Tractor, rear 245 kPa (35 psi)<br />
Heavy truck 895 kPa (130 psi)<br />
Space saver tyres 420 kPa (60 psi)<br />
Industrial <strong>and</strong> heavy earthmoving tyres<br />
Consult manufacturer’s.h<strong>and</strong> book<br />
For passenger vehicles, look in the manufacturer’s tyre digest, or check the<br />
load <strong>and</strong> inflation chart.<br />
Free Air Dispensers<br />
Air pressure available at free air dispensers should be limited unless tyre<br />
inflation is under the control of an employee of the company offering free<br />
air, <strong>for</strong> example the service station. The pressure could be limited to say 275<br />
- 420 kPa (40 - 60 psi), i.e. a pressure unlikely to cause a tyre to rupture,<br />
which would cover most users. If a customer wanted to pump a tyre to a<br />
higher pressure, a staff member could increase available pressure from a<br />
regulator only accessible to the staff member. Some service stations are<br />
adopting this approach now.<br />
Air pressure at free air<br />
dispensers should be<br />
kept to a safe limit.<br />
Signage could simply say that: ‘Pressure available is limited to (275 - 420<br />
kPa (40 - 60 psi)). If higher pressure is required, please refer to one of our<br />
<strong>for</strong>ecourt staff’. It could also refer the owner to the vehicle’s owner/driver<br />
h<strong>and</strong>book <strong>for</strong> appropriate tyre pressures, or warn of pumping up tyres that<br />
have been run flat <strong>for</strong> a period. The sign should be simple, however, if it is<br />
to be read or comprehended.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 56
15: Use of Jacks<br />
Always jack vehicles<br />
on a hard, flat<br />
surface.<br />
Bottle jacks must be<br />
kept upright at all<br />
times. Blocks of solid<br />
hard wood are used to<br />
give extra height to<br />
the jacks.<br />
1<br />
2<br />
3<br />
4<br />
5<br />
6<br />
7<br />
8<br />
9<br />
10<br />
All jacks must be checked <strong>for</strong> safe <strong>and</strong> efficient operation regularly.<br />
Always jack vehicles on a hard, flat surface, never on soft or uneven<br />
ground.<br />
If you are working on the front wheels, chock the rear wheels <strong>and</strong><br />
put the park brake on.<br />
Always use the jack safety catch.<br />
When a wheel is removed, axle st<strong>and</strong>s or blocks must be placed<br />
under the axle. Always use axle st<strong>and</strong>s where practicable. If using<br />
hardwood blocks, use only clean blocks of a regular shape — not<br />
dirty, greasy, misshapen or split blocks.<br />
Attach a warning card to the vehicle’s steering wheel or driver’s<br />
door.<br />
Make sure no one is inside a vehicle being jacked up <strong>and</strong> no one<br />
enters or leans against it while raised.<br />
Keep bottle jacks upright at all times.<br />
Chock appropriate wheels (diagonally opposite to the wheel to be<br />
removed).<br />
Remove key from the ignition.<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 57
16: <strong>Tyre</strong> <strong>Safety</strong> Cages<br />
All tyres on split-rim wheels, <strong>and</strong> detachable flange wheels, must be contained<br />
by a cage guard or other suitable restraining device when being<br />
inflated after being dismantled or repaired. All truck, bus, grader, tractor,<br />
<strong>for</strong>klift <strong>and</strong> other tyres which have a large volume, or are inflated to high<br />
pressures, must be contained by a cage guard or other suitable restraining<br />
device when being inflated after being repaired or otherwise removed from<br />
the wheel. It is strongly recommended that all tyres, including wheelbarrow<br />
tyres, be inflated within a suitable restraint. There have been serious accidents<br />
even with these smaller types of tyres. Cage guards or restraining<br />
devices showing damage or excessive corrosion should be repaired or replaced.<br />
Car wheels <strong>and</strong> tyres are of strong construction have small internal air<br />
volume <strong>and</strong> do not require high pressures. Car tyres pose minimal risk to<br />
the serviceperson, <strong>and</strong> if correct fitting procedures are adhered to then<br />
ruptures will not happen. Beware of divided wheels on small Japanese cars<br />
— see page 00. However, car tyres should be inflated with the jaws of the<br />
tyre fitting machine restraining the wheel.<br />
Examples of tyre<br />
cages <strong>for</strong> permanent<br />
installation. The<br />
st<strong>and</strong>ard design can<br />
be manufactured in<br />
different sizes to suit<br />
tyres fitted by the<br />
customer.<br />
<strong>Tyre</strong> cages should be anchored in workshops, that is they should be bolted<br />
to the floor or restrained to minimise movement.<br />
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17: Identifying<br />
Vehicles Fitted with<br />
Airbags<br />
Air bags are found in many of the vehicles sold in New Zeal<strong>and</strong> since 1993.<br />
They vary from single driver’s side air bag to the multiple air bag systems.<br />
As tyre fitters you must be aware of vehicles that have air bags fitted, to<br />
avoid accidentally deploying them. Accidental deployment may:<br />
• Cause serious injury or even death; <strong>and</strong><br />
• Cost your organisation a lot of money to replace the air bag <strong>and</strong><br />
associated mechanisms.<br />
Ways of Identifying Vehicles Fitted with Air Bags<br />
There are two types of air bag operating systems, mechanical <strong>and</strong> electronic.<br />
Most vehicle manufactures identify their air bag systems extremely well,<br />
with dash warning lamps, <strong>and</strong> labels positioned in view of driver <strong>and</strong> passengers<br />
<strong>and</strong> engraved in the steering wheel <strong>and</strong>/or dash panel, as shown<br />
below:<br />
The owner’s h<strong>and</strong>book may also show that an air bag system is fitted.<br />
Labels<br />
Labels are situated at various locations on the vehicle to show that the<br />
vehicle is equipped with Supplementary Restraint Systems (SRS) (air bags).<br />
The following shows a sample of labels you may come across, indicating that<br />
the car is equipped with SRS.<br />
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On the windscreen.<br />
On the front pillar or maybe on<br />
the sun visor.<br />
In the engine compartment, or underside of the bonnet.<br />
KEY POINT<br />
Some vehicles with air bags may not be easily identified. There is an aftermarket<br />
airbag system available in New Zeal<strong>and</strong>. If you suspect a vehicle has<br />
an air bag but are not, sure ask your supervisor.<br />
Dash warning lamps<br />
A dash-warning lamp is used only on systems that are electrically controlled.<br />
The warning lamp may have different words or symbols depicting air bag<br />
presence, depending on the manufacturer.<br />
<strong>Safety</strong> when dealing with air bags<br />
We cannot overemphasise safety when dealing with a vehicle with an air bag<br />
system. These systems are controlled by the Explosives Act 1957 <strong>and</strong> should<br />
be treated like a loaded shotgun with the safety catch OFF.<br />
However, providing you take some simple safety precautions, you should not<br />
have too many problems with them.<br />
KEY POINT<br />
When working on a vehicle with an air bag, don’t assume you are safe just<br />
because the battery is disconnected.<br />
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Personal <strong>Safety</strong><br />
<strong>Safety</strong> precautions include:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
KEY POINT<br />
Be aware of vehicle safety systems, <strong>and</strong> their function. Electronic<br />
air bags have a dash warning lamp; mechanical air bags do not.<br />
When working around the front wheels of a vehicle, be careful not<br />
to bang <strong>and</strong> or knock the sensors as this could cause air bag<br />
deployment.<br />
When working around the steering wheel <strong>and</strong> the areas of the<br />
passenger’s side air bag (if the vehicle is fitted with dual air bags),<br />
be aware of the air bag systems <strong>and</strong> keep your face away from the<br />
air bag deployment range. Do not probe electrical wires as this<br />
could discharge the air bag system <strong>and</strong> seatbelt pretensioners.<br />
Do not remove the steering wheel without first asking <strong>for</strong> help <strong>and</strong><br />
advice.<br />
Do not bang the steering wheel.<br />
When working around an air bag system, remember that they are explosive<br />
<strong>and</strong> they deploy at speeds ranging from 280 to 480 kph <strong>and</strong> develop approximately<br />
360 bhp, all this within 10-12 thous<strong>and</strong>ths of a second.<br />
The Costs of Accidentally Deploying an Air Bag<br />
Replacement, air bags can cost a lot of money in fact thous<strong>and</strong>s of dollars,<br />
but by accidental deployment they can cause other damage as well, including:<br />
• Smashed front screens;<br />
• Burnt steering wheel;<br />
• Interior clean up;<br />
• Dash replacement in some vehicles.<br />
Then there are the problems <strong>for</strong> your employer, such as explanations to<br />
customers, parts replacement costs, down time <strong>for</strong> business, <strong>and</strong> the worst<br />
thing of all — personnel injury or even death.<br />
FINALLY<br />
• Take all proper safety precautions when working on a vehicle<br />
equipped with air bags.<br />
• Remember to think safety all the time.<br />
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18: The Employer’s<br />
Responsibilities<br />
The <strong>Health</strong> <strong>and</strong> <strong>Safety</strong> in Employment Act 1992 requires employers to take<br />
all practicable steps to ensure the safety of employees while at work. In<br />
particular, employers are required to take all practicable steps to:<br />
(a)<br />
(b)<br />
(c)<br />
(d)<br />
(e)<br />
Provide <strong>and</strong> maintain a safe working environment;<br />
Provide <strong>and</strong> maintain facilities <strong>for</strong> the safety <strong>and</strong> health of employees<br />
at work;<br />
Ensure that machinery <strong>and</strong> equipment is safe <strong>for</strong> employees;<br />
Ensure that working arrangements are not hazardous to employees;<br />
<strong>and</strong><br />
Provide procedures to deal with emergencies that may arise while<br />
employees are at work.<br />
The law requires<br />
mployers to take all<br />
practicable steps to<br />
ensure the safety of<br />
employees while at<br />
work<br />
Employers have responsibilities with regard to significant hazards in the<br />
workplace.<br />
(a)<br />
(b)<br />
(c)<br />
Where practicable, the hazard must be eliminated.<br />
If elimination is not practicable, the hazard must be isolated.<br />
If it is impracticable to eliminate or isolate the hazard completely,<br />
then employers must minimise the likelihood that employees will be<br />
harmed by the hazard.<br />
Where the hazard has not been eliminated or isolated, employers must,<br />
where appropriate:<br />
(a)<br />
(b)<br />
(c)<br />
(d)<br />
Ensure that protective clothing <strong>and</strong> equipment is provided, accessible<br />
<strong>and</strong> used;<br />
Monitor employees’ exposure to the hazard;<br />
Seek the consent of employees to monitor their health; <strong>and</strong><br />
With in<strong>for</strong>med consent, monitor employees’ health.<br />
To summarise important points in the motor industry, employers must<br />
ensure that:<br />
1<br />
2<br />
Every employee is adequately trained <strong>and</strong>/or supervised <strong>for</strong> every<br />
particular job.<br />
Unsafe practices are stopped immediately.<br />
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3<br />
4<br />
5<br />
All employees are supplied with suitable eye protection, overalls,<br />
hearing protection, safety footwear <strong>and</strong> any other items necessary<br />
to protect them from the hazards involved in their work.<br />
Suitable tools <strong>and</strong> equipment are supplied <strong>for</strong> every particular job.<br />
They must be of the correct type <strong>and</strong> in good condition. This<br />
includes cage guards or other suitable restraining devices <strong>for</strong> tyre<br />
inflation.<br />
Manuals, wall charts, or other written instructions are available at<br />
all times <strong>and</strong> cover the type of work being undertaken. Only methods<br />
set out <strong>and</strong> approved by the tyre/wheel manufacturers or<br />
distributors are to be used.<br />
Simply supplying these items is not enough. Employers must also ensure<br />
that they are used or worn. Don’t allow anyone who either works <strong>for</strong> you, or<br />
who is on your premises, to take chances with safety.<br />
Public Access to <strong>Tyre</strong> Change Areas<br />
Workplace or workshop areas where tyre changing is carried out should be<br />
recognised by a sign warning: This is a hazardous area.<br />
If practicable, a waiting room where customers can stay away from the tyre<br />
changing area should be provided.<br />
When public access is unavoidable, tyre change workshop areas where car<br />
tyres are fitted should be separate from areas where heavy vehicle tyres are<br />
fitted.<br />
Clearly identify area where injury may occur. For example, use yellow<br />
painted lines on the workshop floor marking areas to stay clear of.<br />
These areas where tyre changing <strong>and</strong> inflation occurs should be kept clean<br />
<strong>and</strong> clear of all tools <strong>and</strong> debris that could possibly become hazardous <strong>and</strong><br />
cause injury.<br />
Working on Sites as a Contractor<br />
The staff member working within a work site should be inducted into the<br />
site through the system used on that site to in<strong>for</strong>m of specific hazards that<br />
may be present <strong>and</strong> the means of dealing with these hazards. They should<br />
also be aware of all emergency procedures <strong>and</strong> any other appropriate in<strong>for</strong>mation<br />
<strong>for</strong> working on that site.<br />
Areas which should be employee only should have signage: No access unless<br />
under the direct supervision of staff.<br />
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19: The Employee’s<br />
Responsibilities<br />
By law, employees<br />
must take all<br />
practicable steps to<br />
ensure their safety at<br />
work.<br />
Under the <strong>Health</strong> <strong>and</strong> <strong>Safety</strong> in Employment Act 1992, employees must<br />
take all practicable steps to ensure their safety at work, <strong>and</strong> that no action<br />
or inaction causes harm to any other person. Employees are also required to<br />
use the protective clothing <strong>and</strong> equipment supplied <strong>for</strong> the job. Everyone<br />
who installs or repairs tyres should follow these guidelines:<br />
1<br />
2<br />
3<br />
4<br />
5<br />
Don’t attempt any job unless you already know how to do it correctly<br />
<strong>and</strong> safely. Don’t bluff, or you may cause an accident. Ask<br />
your supervisor <strong>for</strong> instructions — that’s what he or she is there<br />
<strong>for</strong>.<br />
Use only the correct tools, clothing <strong>and</strong> equipment <strong>for</strong> the job. If<br />
gear is damaged, don’t use it. If in doubt, see your supervisor <strong>and</strong><br />
ask him or her to examine it, <strong>and</strong> to replace them if necessary.<br />
<strong>Safety</strong> laws oblige you to observe safe work methods. If you are<br />
unsure, stop <strong>and</strong> ask.<br />
Never take chances or let anyone else take chances with safety. In<br />
particular, always wear your eye protection <strong>and</strong> always use tyre<br />
cage guards or other suitable restraining devices when inflating<br />
tyres removed from vehicles <strong>for</strong> any reason.<br />
If you see anyone else not wearing or using safety clothing or<br />
equipment, remind them to do so. You could save their eyesight or<br />
their life.<br />
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20: Employee<br />
Training Schedule<br />
Every employer has an obligation to ensure that employees are adequately<br />
trained in the safe use of all plant, objects, substances <strong>and</strong> protective clothing<br />
<strong>and</strong> equipment they are required to use. If they have not been trained, a<br />
person with the requisite knowledge <strong>and</strong> experience must supervise them.<br />
This is particularly important in the tyre industry, where many injuries are<br />
serious.<br />
Employers are<br />
recommended to<br />
complete <strong>and</strong> maintain<br />
a training schedule <strong>for</strong><br />
each worker.<br />
It is recommended that employers complete <strong>and</strong> maintain a training schedule<br />
<strong>for</strong> each worker. The training schedule can be used to prepare a list<br />
showing each worker’s level of competence in specific tasks. This list should<br />
be made available to both supervisors <strong>and</strong> workers <strong>and</strong> be posted in a<br />
prominent position in the workplace so that those seeking assistance are<br />
directed to a suitably trained person. The chart below is one way of expressing<br />
this in<strong>for</strong>mation, although the <strong>for</strong>mat <strong>and</strong> in<strong>for</strong>mation shown is likely to<br />
vary from one business to another. The list of skills shown is, of course,<br />
incomplete.<br />
Phil Tim Bob Jules Ted<br />
Puncture repair x x x x x<br />
Car tyres x x x x x<br />
Use of jacks x x x x x<br />
Off-vehicle balancing x x x x<br />
On-vehicle balancing x x x x<br />
Divided rims x x x x x<br />
Tubeless truck tyres x x x<br />
Wide-base rims x x x<br />
H.T. licence x x x<br />
Outside repair unit x x<br />
Compressor maintenance x x<br />
Wheel alignment x x x<br />
<strong>Tyre</strong> companies, some polytechnics, <strong>and</strong> the Motor Industry Training Organisation<br />
have training courses <strong>and</strong> training resources, including books <strong>and</strong><br />
videos. In the first instance, you should ask your tyre suppliers <strong>for</strong> training<br />
aids.<br />
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21: Where to Get<br />
Advice<br />
If you have any doubts or questions about safety, ask your supervisor first.<br />
If this is not possible, or the matter is not properly dealt with, you should<br />
approach either your firm’s safety officer or your union delegate. If there is<br />
no safety officer or union delegate <strong>and</strong> you are still not satisfied that the job<br />
is safe, then contact a factory inspector at your nearest Occupational <strong>Safety</strong><br />
<strong>and</strong> <strong>Health</strong> Service (OSH) office. Employers who have any questions concerning<br />
safety or safety legislation should also contact their nearest OSH<br />
office.<br />
Technical matters should be referred to the organisations whose contact<br />
details are given in this book.<br />
Any enquiries regarding st<strong>and</strong>ards should be referred to the St<strong>and</strong>ards<br />
Association of New Zeal<strong>and</strong>.<br />
L<strong>and</strong> Transport Rule: <strong>Tyre</strong>s <strong>and</strong> Wheels<br />
L<strong>and</strong> Transport Rule: <strong>Tyre</strong>s <strong>and</strong> Wheels is proposed transport legislation at<br />
this time (March 2001). If passed, it will replace existing l<strong>and</strong> transport<br />
legislation <strong>for</strong> tyres <strong>and</strong> wheels. The new legislation is intended to ensure<br />
that all vehicles have tyres <strong>and</strong> wheels that meet an acceptable level of<br />
safety when fitted, <strong>and</strong> throughout their on-road life. The rule is applicable<br />
to all vehicles used on the road at any time, <strong>and</strong> covers modifications <strong>and</strong><br />
repairs.<br />
<strong>Tyre</strong> <strong>Safety</strong> Issue Boundary Between OSH <strong>and</strong> LTSA<br />
The LTSA has responsibility <strong>for</strong> vehicle safety on public roads. This responsibility<br />
includes the vehicle tyres, <strong>and</strong> where a spare wheel is carried by a<br />
vehicle, the safety aspects of spare wheel security.<br />
OSH has responsibility <strong>for</strong> safety in the manufacture, fitting, repair, <strong>and</strong><br />
storage of tyres in places of work.<br />
Web Sites (NZ)<br />
L<strong>and</strong> Transport <strong>Safety</strong> Authority<br />
http://www.ltsa.<strong>govt</strong>.<strong>nz</strong>/homepage.shtml<br />
Occupational <strong>Safety</strong> <strong>and</strong> <strong>Health</strong> Service of the Department of Labour, New<br />
Zeal<strong>and</strong><br />
http://www.osh.dol.<strong>govt</strong>.<strong>nz</strong><br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 66
References<br />
Books <strong>and</strong> St<strong>and</strong>ards<br />
Vehicle St<strong>and</strong>ards: What makes car safety tick, L<strong>and</strong> Transport <strong>Safety</strong> Authority;<br />
pp 19-21, <strong>Tyre</strong>s<br />
Compressed air safety, HSE Books, 2nd edition, 1998<br />
Guidance on the h<strong>and</strong>ling, storage <strong>and</strong> transport of airbags <strong>and</strong> seat belt<br />
pretensioners, HSE Books, 1998<br />
A guide to the h<strong>and</strong>ling <strong>and</strong> storage of airbags <strong>and</strong> seat belt pretensioners at<br />
garages <strong>and</strong> motor vehicle repair workshops, HSE Books, 1998<br />
<strong>Tyre</strong>s, wheels <strong>and</strong> rim assemblies: Safe removal, assembly <strong>and</strong> inflation,<br />
Tasmania Department of Labour <strong>and</strong> Industry, 1986<br />
Assembling truck <strong>and</strong> tractor tyres <strong>and</strong> rims, WorkCover Authority of New<br />
South Wales, (leaflet, illus.), 1991<br />
AS/NZS 1268:1996 Equipment <strong>for</strong> checking pressure <strong>and</strong> inflation of tyres.<br />
(Specifies minimum requirements <strong>for</strong> tyre pressure gauging equipment when<br />
used to measure, inflate, control or adjust the pressure of tyres used on<br />
road vehicles.)<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 67<br />
Joint Australian/New Zeal<strong>and</strong> St<strong>and</strong>ards<br />
NZS 5423:1996 Specification <strong>for</strong> repairing <strong>and</strong> retreading car, truck <strong>and</strong> bus<br />
tyres Amend: 1 1998<br />
(Specifies the minimum requirements <strong>for</strong> the repairing <strong>and</strong> retreading of<br />
car, truck <strong>and</strong> bus pneumatic tyres used in highway service. It specifies<br />
certain constructional features such as the examination, limits of damage,<br />
preparations <strong>and</strong> permissible repairs of the tyre carcass be<strong>for</strong>e processing,<br />
<strong>and</strong> the marking <strong>and</strong> inspection of the tyre after curing. Minimum per<strong>for</strong>mance<br />
levels are also given. Except where otherwise stated, the requirements<br />
apply to both tubed <strong>and</strong> tubeless tyres.)<br />
Cited in Import Control (<strong>Tyre</strong>s) Conditional Prohibition Order 1996<br />
NZS 5453:1989 New tyres <strong>for</strong> passenger vehicles<br />
(Specifies requirements of strength, construction <strong>and</strong> st<strong>and</strong>ard pressure/<br />
load relationships <strong>for</strong> new pneumatic tyres <strong>for</strong> passenger cars <strong>and</strong> prescribes<br />
tests required <strong>for</strong> their acceptance.)<br />
Cited in Transport (Vehicle St<strong>and</strong>ards) Regulations 1990, Import Control<br />
(<strong>Tyre</strong>s) Conditional Prohibition Order 1996<br />
NZS 5464: 1990 Pneumatic tyres - Light truck <strong>and</strong> truck/bus - New (=AS<br />
2230-1990)<br />
(Specifies requirements <strong>for</strong> physical dimensions, per<strong>for</strong>mance, <strong>and</strong> marking<br />
<strong>for</strong> new pneumatic light truck, <strong>and</strong> truck/bus tyres designed primarily <strong>for</strong><br />
on-road use.)
Cited in Transport (Vehicle St<strong>and</strong>ards) Regulations 1990; Import Control<br />
(<strong>Tyre</strong>s) Conditional Prohibition Order 1996<br />
Other <strong>Tyre</strong>-Related Web Sites<br />
Beaurepaires<br />
http://www.beaurepaires.co.<strong>nz</strong><br />
Bridgestone — Answers to some of the most common questions about tyres<br />
http://www.bridgestone-tyres.com/faq.htm<br />
Dunlop <strong>Tyre</strong>s Ltd.<br />
http://www.dunloptyres.co.uk/00home.html<br />
National Highway Traffic <strong>Safety</strong> Administration (U.S.A.)<br />
http://www.nhtsa.dot.gov<br />
National <strong>Tyre</strong> Distributors Association, United Kingdom<br />
http://www.ntda.co.uk/safety.htm<br />
OSHA Regulations (St<strong>and</strong>ards - 29 CFR)<br />
Servicing multi-piece <strong>and</strong> single-piece rim wheels. - 1910.177<br />
http://www.osha-slc.gov/OshStd_data/1910_0177.html<br />
<strong>Safety</strong>Line, an on-line in<strong>for</strong>mation service provided by WorkSafe Western<br />
Australia<br />
http://sage.wt.com.au/safetyline<br />
<strong>Tyre</strong> <strong>Safety</strong> Australia<br />
http://www.worksafe.gov.au<br />
<strong>Health</strong> <strong>and</strong> <strong>Safety</strong> <strong>Guidelines</strong> <strong>for</strong> <strong>Tyre</strong> <strong>Fitters</strong> 68
Appendix 1: Wheel<br />
Restraint Device<br />
Example of a portable restraint device<br />
which packs in a compact space <strong>for</strong><br />
convenient transport to field work.<br />
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Appendix 2: <strong>Tyre</strong><br />
Construction<br />
Three types of tyre constructions are common in New Zeal<strong>and</strong>, namely<br />
crossply (bias ply), textile radial, <strong>and</strong> steel radial construction.<br />
The following diagrams illustrate the basis of these constructions.<br />
Crossply (or Bias Py) Construction.<br />
This construction has the ply cords extend to the beads <strong>and</strong> laid<br />
at opposing angles of approximately 40 0 to the tread centreline.<br />
The carcass is normally of either nylon or polyester construction.<br />
Textile Radial Construction<br />
The textile radial ply tyre has its body plies laid at an angle of<br />
approximately 90 0 to the tread centreline. The casing material is<br />
usually of textile cords, as are the breaker plies or belts which<br />
sit centrally on the crown of the tyre below the tread. The body<br />
plies which run radially from bead to bead (giving the tyre its<br />
name) provide very flexible sidewalls compared to the crossply<br />
tyre, but the tread area is rein<strong>for</strong>ced to a heavier degree, providing<br />
improved mileage over the traditional crossply tyre.<br />
Steel-Belted Radial Construction<br />
Similar in construction to the textile radial tyre, the fundamental<br />
difference is the replacement of the multiple textile belts<br />
with two belts of high-tensile steel. These tough steel belts<br />
which encircle the casing provide an inextensible foundation <strong>for</strong><br />
the tread to sit on, providing superior cornering <strong>and</strong> high speed<br />
h<strong>and</strong>ling dynamics, together with longer tyre life.<br />
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Appendix 3: Glossary<br />
of Terms<br />
Approved Rim Widths Codes<br />
The only allowable rim widths <strong>for</strong> a<br />
specific size of tyre.<br />
Aspect Ratio<br />
This is the ratio between the tyre section<br />
width <strong>and</strong> the height of the sidewall.<br />
Early tyre designs had an aspect ratio of<br />
100%, which means that the section<br />
height <strong>and</strong> width are equal.<br />
With modern cars capable of much higher speeds, the tyre manufacturers<br />
have now designed tyres with decreased aspect ratios to complement the<br />
increased per<strong>for</strong>mance of vehicles. Today’s modern sports cars are now<br />
fitted with 50%, 45%, 40%, or even 35% aspect ratios.<br />
Asymmetric Patterns<br />
An asymmetric tread pattern generally consists of dissimilar tread pattern<br />
elements placed radially opposite each other in order to optimise pattern<br />
characteristics.<br />
Bead<br />
That part of a pneumatic tyre which fits <strong>and</strong> holds the tyre securely onto<br />
the wheel rim. It consists of a coil of high-tensile steel wire, treated to give<br />
good adhesion with rubber, <strong>and</strong> encased in a “matrix” of hard rubber.<br />
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Breaker<br />
A strip of rubber-coated cord fabric, or steel cord, fitted between the tread<br />
<strong>and</strong> casing of a radial ply tyre, running on a bias circumferentially around<br />
the tyre.<br />
Cap <strong>and</strong> Base<br />
A pneumatic tyre tread <strong>for</strong>med from two separate strips of compound each<br />
having different physical characteristics; the upper strip or cap <strong>for</strong>ming the<br />
tread pattern <strong>and</strong> the lower strip of base <strong>for</strong>ming the undertread.<br />
Chafer<br />
A strip of rubberised cross-woven fabric fitted around the part of the tyre<br />
bead which comes into contact with the rim.<br />
Clinch<br />
The area of the sidewall of a pneumatic tyre immediately above the rim<br />
flange where severe stress occurs in service.<br />
Compound<br />
Natural or synthetic rubber, or a blend of both, treated with various chemicals<br />
<strong>and</strong> other materials to give specific properties required <strong>for</strong> various<br />
commercial rubber products.<br />
Deflection<br />
The degree to which the section of an inflated tyre distorts or deflects<br />
under load. The ratio of the loaded section height to the unloaded section<br />
height of a tyre, expressed as a percentage.<br />
Directional Tread<br />
A tread <strong>for</strong>med with “Chevron” grooves used on tyres providing good traction<br />
combined with self cleaning properties. <strong>Tyre</strong>s with directional treads<br />
must be fitted with the point of the chevron pointing in the direction of<br />
travel, otherwise traction will be lost.<br />
D.O.T.<br />
Department of Transportation (USA) tyre safety st<strong>and</strong>ards. The letters<br />
appear on the sidewall of passenger tyres manufactured in America or <strong>for</strong><br />
the American market.<br />
Flap<br />
A circular strip of rubber or fabric-rein<strong>for</strong>ced rubber used in pneumatic<br />
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tyres to prevent chafing of the inner tube on the rim. Quite commonly<br />
known in New Zeal<strong>and</strong> as a “Rustb<strong>and</strong>”.<br />
Footprint<br />
The ground contact area of a tyre tread.<br />
Inner Liner<br />
The air retaining part of a tubeless tyre. It is an integral part of the tyre<br />
<strong>and</strong> consists of a sheet of special rubber compound fitted to the underside<br />
of the first (inside) casing ply.<br />
Load Index<br />
A numerical system of marking tyres to indicate their load-carrying limits.<br />
The load index is related to ply rating.<br />
Load range<br />
The term “Load Range”, <strong>and</strong> its designating letter, is used to identify a<br />
given tyre size with its load <strong>and</strong> inflation limits when used <strong>for</strong> a specific<br />
type of service, as defined in the TRA tables. Load ranges are normally<br />
only used on tyres of USA or Canadian manufacture. (A = 2PR, B = 4PR,<br />
C = 6PR etc.)<br />
Loaded Section Width<br />
The width of the cross section of a tyre under load.<br />
Low Profile <strong>Tyre</strong>s<br />
Any tyre having a section height to section width ratio (aspect ratio) of 80%<br />
or lower.<br />
Maximum Inflation Pressure<br />
Maximum cold pressure required to carry the maximum load.<br />
Maximum Load<br />
Maximum carrying capacity of the tyre when run at maximum inflation<br />
pressure, at a given speed.<br />
Millimetre <strong>Tyre</strong>s<br />
<strong>Tyre</strong>s marked with the section width in millimetres, <strong>and</strong> the rim diameter in<br />
inches, e.g. 165 R 13.<br />
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Minimum Dual Spacing<br />
The minimum recommended distance between centrelines of dual-mounted<br />
tyres to avoid touching or chafing in the flex area.<br />
Non-directional Tread<br />
A general-purpose tread pattern designed so that the tyre can be run in<br />
either direction without loss of traction or self-cleaning properties.<br />
Overall Diameter (od)<br />
The diameter of an unloaded tyre, mounted on its recommended rim <strong>and</strong><br />
inflated to service pressure.<br />
Plies<br />
Sheets of rubber-coated textile or steel wire cords from which the casing of<br />
a tyre is constructed. A single ply consists of a sheet of cord fabric or steel<br />
in which the cords run parallel to one another <strong>and</strong> are insulated from each<br />
other by a layer of resilient rubber compound.<br />
Ply Rating<br />
The term “ply rating” is now used to identify a given tyre with its maximum<br />
recommended load <strong>for</strong> its specific job. It is an index of tyre strength <strong>and</strong><br />
does not necessarily represent the number of actual plies. The ply rating<br />
system is being discontinued in favour of load indices.<br />
Rim Width<br />
The section of a wheel on which the beads of a pneumatic tyre are fitted.<br />
Rim Fitting Line<br />
A narrow rib, part of the sidewall rubber running circumferentially around a<br />
tyre just above the bead, used as a guide line to check that a tyre when<br />
fitted to its wheel is correctly seated on the rim.<br />
Rim Flange<br />
The shoulders of the rim of a wheel which fit against the face of the bead<br />
<strong>and</strong> which hold the tyre on the rim.<br />
Section Height (SH)<br />
The distance from the bead seat to the outer tread contour of the inflated<br />
tyre — at the centreline.<br />
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Section Width (SW)<br />
The width of the inflated tyre section, excluding any lettering or decoration.<br />
Static Loaded Radius (SLR)<br />
The st<strong>and</strong>ing height from the road surface to the axle centre under nominal<br />
load/inflation conditions.<br />
Tread<br />
The wearing surface of the tyre, i.e. that part of the tyre which makes<br />
contact with the road.<br />
Tread Wear Indicators<br />
Various devices incorporated in the base of the tread pattern of a tyre,<br />
usually in the <strong>for</strong>m of small raised plat<strong>for</strong>ms spaced at intervals around the<br />
base of the circumferential grooves of the pattern.<br />
Tube<br />
The tube or “inner tube” is part of a tyre assembly <strong>and</strong> holds the air under<br />
pressure.<br />
Wheel Offset<br />
Distance from the rim centreline to the inner (hub contact) face of the<br />
wheel disk, measured in millimetres. A wheel with a positive offset will have<br />
the centreline inboard of the contact face, whereas a wheel with negative<br />
offset will have the wheel centreline outboard of the contact face.<br />
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