Acceptable Quality Level (AQL) - Ansell Healthcare Europe

anselleurope

Acceptable Quality Level (AQL) - Ansell Healthcare Europe

Acceptable Quality Level

(AQL)

Acceptable Quality Level (AQL) is a statistical

measure of the consistency or quality predictor of

manufactured goods. It applies to all batch type

production as a means of ensuring that the process

average meets the standards determined. For

medical products, it is critical that the products are

manufactured to a very high standard at all times.

Surgical and examination gloves are essential barrier

protection items and neither you nor your patients

want to receive a defective glove, however very rarely

this may occur.

What is a homogeneous

batch?

The term homogeneous batch refers to products

that are made in groups and from the exact same

parameters. Gloves, for example, would be from such

a batch if the latex used, production settings and

finishing processes are all exactly the same over that

period. Any alteration at any stage of production is

considered a new batch.

Process average

This term refers to the manufacturing process’

average defect or reject rate. It is critical as an

indicator of the manufacturing quality. To assess this

a set number of gloves taken from the production

line every two minutes are subjected to a full range of

quality tests. The reject rate is the failure percentage

of the product. Production processes are kept in tight

tolerances with the use of control charts.

Control charts

These charts are like recipe cards and they outline all

the parameters for the product being manufactured.

In the case of Ansell gloves, for example, they would

contain the latex and chemical mix for the dip, the

production speed, oven temperatures, type of former

to be used and every parameter including the post

production processing. The tighter the parameters or

tolerances in the control chart, the more consistent

the quality of production will be. Every manufacturing

step of an Ansell glove is documented and mapped

for the production process to ensure our gloves are of

the highest possible standards.

AQL sampling

The table on the reverse is an example of the

arbitrary statistical system for AQL testing. You will

see that inspection levels are set at ‘Level I’. This

is the industry standard for medical grade quality

inspection. Variance to another inspection level e.g.

for machinery, would prescribe different tolerance

levels. The variable parameters are:

1. The lot/batch size.

2. The inspection level – determined by

AS/NZS4079:1997 and 4011:1997 at level I.

3. AQL level determined.

Depending on these points, the number of allowable

failures per sample test will determine the arbitrary

‘yes’ or ‘no’ for that batch to statistically pass the AQL

standard. Failure will mean that the manufacturer has

to inspect every piece of the batch to remove defective

products. This is time consuming and expensive.

Therefore, it is better to build the quality assurance

system into the production process rather than use

inspection at a later stage to remove defects which

occur through inexact production processes.


Curve number Ansell 2 3 World standard 5

AQL 0.065 0.9 1.1 1.5 2.5

Inspection level II II II II II

Lot/batch size 10,000 10,000 10,000 10,000 10,000

Sample size 200 200 200 200 200

Acceptance number 0 3 5 7 10

Curves for Sampling Plan

Probability

of

Acceptance

1.200000

1.000000

0.800000

0.600000

0.400000

0.200000

0.000000

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 9.5 10 10.5 11 11.5 12

You can see in the graph that the lot (batch) size and

inspection level are the same and only the AQL level

varies. At an AQL of 2.5 the acceptable number of

defects in the sample lot is 10. This falls to 7 allowable

defects at an AQL of 1.5 (the world surgical glove

standard). Ansell’s AQL level of 0.065 (before packaging)

means that a single defect in the sample lot will result

in an AQL failure, resulting in every glove in the

production batch being inspected. As previously stated,

this is time consuming and expensive. Setting an AQL

so low is only possible if the quality and consistency of

production is very high and tightly controlled.

An AQL test is an absolute test i.e. ‘yes’ it passes or

‘no’ the batch cannot be released. However the AQL

test is a direct reflection on the manufacturing process

quality and conformity. Ansell’s AQL level of 0.065

Percent Defective

AQL 0.065 INSP-II AQL 0.9 INSP-II AQL 1.1 INSP-II AQL 1.5 INSP-II AQL 2.5 INSP-II

Ansell Healthcare Europe N.V.

Riverside Business Park, Spey House, Boulevard International 55, B-1070 Brussels, Belgium

Tel. +32 (0) 2 528 74 00 Fax +32 (0) 2 528 74 01 Fax Customer Service +32 (2) 528 74 03

http://www.anselleurope.com E-mail info@eu.ansell.com

(before packaging) ensures that you will consistently be

assured of the highest quality barrier protection. There is

however, as with everything a very rare occasion when a

glove may be defective.

What is the AQL level of the

gloves you are using now?

Ansell’s AQL standards:

• Surgical gloves is 0.065 before packaging

(World standard 1.5).

• Examination gloves 1.5 (World standard 2.5).

Be Ansell Sure.

More magazines by this user
Similar magazines