GB 9644-1988 Unplasticized polyvinyl chloride (PVC-U) pipes and fittings for drinking water supply-Extractability of lead tin、cadmium and mercury occurring as impurities-Test method and pemitted levels
Unplasticized polyvinyl chloride (PVC-U) pipes and fittings for drinking water supply-Extractability of lead tin、cadmium and mercury occurring as impurities-Test method and pemitted levels