The purpose of this SAE Aerospace Recommended Practice (ARP) is to ensure conformance for each product characteristic being verified in a lot, without maintaining information from previous lots. ARP9013/1 specifies a product acceptance system for isolated lots. For example, isolated lot sampling avoids keeping track of the normal, tightened, and reduced levels of sampling formerly used in MIL-STD-105 and currently used in ANSI/ASQC Z1.4. Because those switching rules provided significant long-term protection for product quality, these isolated lot tables replace that protection in other ways.