How to pick between ANSI Z1.4 vs. ISO2859-1 for AQL Inspection? What are the major differences?

[uptempos]

I can't find anywhere on Google on when its appropriate or how suppliers end up deciding on Ansi Z1.4 vs. ISO2859-1.
Can someone please provide guidance?

I understand they both come from the obsolete MIL-STD105E.
I also understand ANSI Z1.4 is recognized by the US FDA.
It appears ISO2859-1 is more internationally recognized in countries such as Japan, rest of Asia? Or is this not true?
Both have switching rules.

So how do people decide to follow ISO-2859-1 or ANSI Z1.4?

 

[Mike S.]

I've never read ISO2859 so I can't provide detail on their similarities and differences, but my gut tells me they are probably very similar. If I could I'd get a copy of each and compare them.

A lot goes into deciding what sampling plan to use, or even if sampling is appropriate. What is it you are trying to accomplish? What is your industry? Do your customers specify any sampling requirements? Typical lot sizes, typical defect levels, risk tolerance, cost per inspection, destructive vs. non-destructive testing, etc. are all considerations.

Another type of sampling plan you may consider is C=0 sampling -- search for ASQ H1331 "Zero Acceptance Number Sampling Plans" by N.L. Squeglia.

 

[lizVR]

In a related question, if you are using the Zero Acceptance plans, can you claim compliance to Z1.4, which is a recognized standard. I know the Zero Acceptance is based on the Z1.4 but are they aligned enough for equivalence?

 

[Mike S.]

In a related question, if you are using the Zero Acceptance plans, can you claim compliance to Z1.4, which is a recognized standard. I know the Zero Acceptance is based on the Z1.4 but are they aligned enough for equivalence?

You can't claim "compliance" to Z1.4 if using ASQ H1331 "Zero Acceptance Number Sampling Plans". Whether or not they are "aligned enough for equivalence" you and/or your customer would need to decide. The latter plan has a considerable amount of information within comparing the two plans.

 

[lizVR]

Thank you! Yes, I agree that this makes sense as there isn't perfect alignment between the two. I appreciate the input as it reinforces my initial assumption and helps with my CAPA.