I have worked for 2 companies that have used the AQL Inspectors Ruler which is based on ANSI/ASQ Z1.4-2003. This standard is for attributes testing, but I see that people are using it with variable data points.

My question is, If you are inspecting data that is variable, can you state that it falls under attribute sampling if you say: Yes, it's in tolerance/No, it's out of tolerance?

I understand that by doing this you lose sight on process variability, but I just want to know if we can get away with this method.:confused:

If I understand your question, the answer is yes.

For example, let's say you are measuring length and the spec is 3 +/- 1 and you record variable data for each sample. If your Z1.4 sampling plan calls for 13 samples, and all 13 measurements fall within 3 +/- 1, you can approve the lot via a Z1.4 attribute sampling plan.

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Yes, it did.

Thanks.