Introduction to Fire Safety Management

this situation it will be necessary to install a door closing
device to retain the door in the closed position. As
above this system should not be used where public have
access.
Electromagnetic locks – these units provide a great
amount of fl exibility in the control of escape doors. They
must be wired into an automatic fi re warning/smoke
detection system and they must have a local override
such as a break glass call point adjacent to which operating
instructions would be displayed. Free entry and exit
can also be time controlled or operated from a remote
station. This type of hardware is relatively easy to fi t,
reliable and, compared with panic bolts, fairly unobtrusive.
It is simply an electromagnet which, while it is
energised, holds the door closed. When the power is cut,
which could be effected by the alarm system, the magnet
releases and the door is free to open. If the door needs to
be opened in the normal course of events, a key switch
on the frame could turn off the current. The system must
fail in the safe/open position.
Keys in boxes
The use of these products is not acceptable
where emergency escape doors are concerned.
Where they are installed it is not unusual
to see the keys missing from the boxes.
In the event of the need to escape from a
smoke fi lled area it may not be easy to fi nd the
box, smash the glass, remove the key from
among the broken glass, fi nd the lock, insert
the key and open the door. In view of the
alternatives available there is no need to rely
on this method of providing emergency exit.
(There are some certifi cated premises with
this arrangement, which is not retrospective.)
9.5.5 Protection of escape routes
The aim, when planning or assessing escape routes, is
to comply with the requirements of the law and ensure
occupants have adequate means of escape. Although
the law is not prescriptive and requires only compliance
to functional requirements, the guidance provided on
how to achieve adequate means of escape is helpfully
detailed and allows the easier planning or assessment
of various means of escape. The guidance contains a
number of specifi c principles, which should be complied
with in most cases.
As is the case with all the guidance relating to fi re
safety it is not necessary to follow it exactly, provided
Fire protection in buildings
that the functional requirement of achieving adequate
means of escape is achieved in other ways.
The following key points with regard to escape
routes should be considered:
➤ Access to storey exits
➤ Separation of circulation routes from stairways
➤ Storey/fl oors divided into different uses
➤ Storey divided into different occupancies
➤ The height of escape routes
➤ Separation of high risk areas
➤ Protection of dead-ends
➤ The subdivision of long corridors.
Access to storey exits – a storey, or fl oor, with more
than one escape stair should be planned so that occupants
do not have to pass through one stairway to reach
another, although it is acceptable to pass through one
stairway’s protected lobby to reach another stair.
Separation of circulation routes from stairways –
any stairway and any associated exit passageway
should not form part of the primary circulation route
between different parts of the building at the same level.
This is because self-closing fi re doors can be rendered
ineffective as a result of constant use, or because some
occupants might regard them as an impediment; and
wedge them open or remove the self-closing devices.
The exception to this is where the doors are fi tted
with an automatic release mechanism operated in
conjunction with the automatic fi re detection and alarm
system.
Storeys divided into different uses – where a
storey contains an area ancillary to the main use of the
building, for the consumption of food and/or drink, such
as a canteen or mess room, then:
➤ Not less than two escape routes should be provided
from each such area
➤ One of the escape routes should lead directly to a
storey exit without entering the remainder of the storey,
a kitchen or an area of special fi re hazard.
Storeys divided into different occupancies –
where a storey is divided into separate occupancies (i.e.
where there are separate ownerships or tenancies of
different organisations):
➤ The means of escape from each occupancy should
not pass through any other
➤ If the means of escape includes a common corridor
or circulation space, then either it should be a
protected corridor, or a suitable automatic fi re
detection and alarm system should be installed
throughout the storey.
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