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Inspection Standard

Sampling Method

Inspection samples are selected according to MIL-STD-105D standard at random so they represent actual production quality of customer order, once the production lot has been completed and packed. The method is widely used to decide whether or not to accept or reject a production lot without checking every single item of the lot.

China inspections - inspection standard 001

Table A shows sample size codes at different lot quantities. Generally, we follow MIL-STD-105D (IIA) simple sampling plan for a general inspection and MIL-STD-105D (IIIA) double sampling plan for destructive or complicated test requirements.

AQL Table

Omnitech use AQL tables (Acceptable Quality Levels) to measure acceptable levels of quality and to establish a maximum allowable error rate or variation from the standard. Customer decides on the levels (acceptable levels) but we may recommend if customer doesn't have own. These tables are a US standard with equivalents in all international standardization organizations.

Since simple sampling plan is most commonly used in general inspection, our quality engineer has combined both sample size codes and acceptance levels to a Table B for easy reference. This table indicates the sample size and relative acceptance level at specific lot quantity.

Example: For an inspection at a 3,000 lot quantity, with an AQL (Acceptable Quality Level) of 2.5, Table B indicates that the sampling size should be 125 units, the corresponding acceptance number is 7 but the rejection number is 8..

China inspections - inspection standard 002

Critical Defect

The Critical Defect corresponds to a defect likely to result in unsafe conditions for end-users. You can provide your own list of critical defects to be inspected. Omnitech's default Critical Defect is 0.

Major Defect

The Major Defect corresponds to the defect that is likely to result in failure, or reduced usability of the product unit. A product is said to have a Major Defect when it is not dangerous but cannot be sold because of the defect. We will have them from appearance, material, function, packing, shipping mark etc. to be inspected. Omnitech default Major Defect AQL is 1.5.

Minor Defect

The Minor Defect corresponds to a defect that is not likely to reduce the usability of the product unit for its intended purpose. A Minor Defect is nevertheless a workmanship defect beyond the defined quality standard. We will have them from appearance, material, function, packing, shipping mark etc. to be inspected. Omnitech default Minor Defect AQL is 4.0.

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