AQL
LRQMS apply MIL-STD-105E(AQL) to take sample and inspection standard. The inspection chart is based on America starndard. All countries' standard organization and international organization all have equivalent inspection chart(like ANSI/ASQC Z1.4、ISO 2859、NF06-022、BS 6001 and DIN 40080). This inspection standard, to pick up sample and inspect, then to decide whether the lot can be accepted, and not necessary to inspect every products of the lot, is widely applied worldwide.
* Accord to Customer's requirement to decide AQL Level
Sampling and inspection
Sampling and inspection is applied to decide accept or reject the lot. Firstly to pick up samples, then inspect the samples, and decide accept or reject the lot according to the inspection result.
Lot
Lot is a combination of many products of same size, type, production condition and time. Sample will be taken from the lot, then to decide if the lot is acceptable.
Normal sampling and inspection standard
Sampling standard represents the accuracy of the sampling method. For certain quantity of one lot, improving sampling standard means more sample will be taken and inspected.
Normal sampling standard consists level I, level II and level III.
Our defaulted sampling leve is Level II.
Special Sampling sampling and inspection standard
We can also do special sampling and inspection standard as customer's need.
Special sampling and inspection standard consists of S1, S2, S3 and S4.
Sampling Code.
Sample code is based on lot and sampling level.
Sampling size
Samples that are chosen for inspection.
Acceptable level and defective classification.
Normally, we classify 3 level defectives,
* Critical defective
* Major defective
* Minor defective
Critical defective
Critical defective is the products do not meet compulsary agency and regulation, or risk consumers' safety and property.
LRQMS default critical defective value as zero.
Major defective
Major defective is the product can still be used of lower quality or cosmetic defective, will not have safety issue.
LRQMS default major defective value as 0.25
Minor defective
Minor defective is product can be used, may have impact for selling and deviation from the quality standard.
LRQMS default minor defective value as 1.0.
How to define sampling quantity and acceptable quantity
Assuming to inspect one lot product of 7000pcs, per quality standard G-II, chart B shows sampling quantity should be 200pcs. According to quality standard 0.25/1.0(major defective/minor defective), the corresponding acceptable quantity is 1pc/5pcs. If major defective is more than 1pc or minor defective is more than 5pcs, the lot will be rejected.
According to the inspection standard of 0, 0.25 and 1.0,
The defective products can be accepted for this lot are, Zero for critical defective, 1pc for major defective, and 5pcs for minor defective.
In the case of random sampling, if no critical defective is found, when major defective is more than 1pc or minor defective is more than 5pcs, then the lot will be rejected.