August 17, 2026

Here is a fact most buyers never use against their supplier: the pipe product standard already contains an inspection plan. GB/T 18742.2-2017, the PP-R pipe part of China’s adoption of ISO 15874, mandates sampling inspection by GB/T 2828.1 at AQL 4.0 for appearance and dimensions. GB/T 2828.1 is the same attribute sampling scheme as ISO […]