Oh. Well, Figure B1 kinda forces you into some rather high inspection levels. It is not a mistake in the customer requirements. Probability of conformance is another way of saying a protection level to the consumer. ERP = 1- probability of conformance.
So for example if you are inspecting a machined part with a thickness tolerance of +/- .004" you need to use an ARP9013 sampling plan with IRR of >/= 97% or ERP </= 3%.
So for example if you are inspecting a machined part with a thickness tolerance of +/- .004" you need to use an ARP9013 sampling plan with IRR of >/= 97% or ERP </= 3%.