AQL (Acceptance Quality Limit)
An AQL (Acceptance Quality Limit) Chart is shown below. The AQL is the quality level that is the worst tolerable process average when a continuing series of lots is submitted for acceptance sampling.
HOW TO READ THE AQL CHART
ASTM and NFPA standards identify AQL and Inspection levels for critical quality parameters listed below:
This chart is based on ANSI / ASQ Z1.4-2003 requirements.
Parameter |
ASTM
|
NFPA
|
FIRSTLINE GLOVES
|
|
Inspection Level
|
AQL
|
Inspection Level
|
AQL
|
Inspection Level
|
AQL
|
|
Watertight
|
G-1
|
2.5
|
G-1
|
1.5
|
G-1
|
<1.5
|
|
Dimensions & Physical Properties
|
S-2
|
4.0
|
S-2
|
Not Applied
AVG Driven
|
S-2
|
4.0
|
Since most glove production runs exceed 500,000 pieces, for watertight, the sample size code is N, for dimensions and physical properties, it is E. Sample code N requires that 500 samples are tested, while E requires that 13 pieces are tested. For watertight, at an AQL of 2.5, 21 gloves may fail, while for dimensions and physical parameters, at an AQL of 4.0, only 1 of the 13 pieces tested may fail.
If pass fail data is to be used as an indicator of product quality consistency, then it is necessary to conduct testing on a specific lot size, for each and every lot. Testing randomly, unless a process is deemed to be capable of producing no defects, only provides a “snapshot” of quality and does not serve as an indicator of individual lot quality or process control.
Furthermore, it is critical that lot size maximums be established based on process control. Many manufacturers will present data, based on a single production run, or a production run that encompasses millions and millions of gloves produced. This type of “smoke and mirrors” quality data does not provide the end user with the assurance that each and every controlled lot is produced to stringent quality standards, nor does it guarantee consistency with every shipment.
The chart shown identifies the average AQL levels achieved for watertight properties for FirstLine Gloves various models. FirstLine’s defect levels test far below ASTM or NFPA requirements. FirstLine Gloves partners with our factory and employs statistical process control principles to achieve reduced defects and superior quality; through our commitment to continuous improvement.
The link below, from the website AQL Inspectors Rule, provides definitions of all AQL associated terminology.
http://www.aqlinspectorsrule.com/manual/dictionary.html
Download AQL Chart
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