给水用管材原来大部分是使用铸铁管和镀锌铁管 ,其次是少量的ＰＶＣ管。对于ＰＶＣ管的重金属含量检验 ,原国家标准ＧＢ96 44 -88要求铅含量应小于 5× 10 -7。随着时代的进步和环保意识的加强 ,为克服铁管对水源的二次污染 ,国家已决定逐步淘汰铸铁管和镀锌管在供输水方面的使 Most of the original water supply pipe is cast iron pipe and galvanized iron pipe, followed by a small amount of PVC pipe. For PVC pipe heavy metal content test, the original national standard GB96 44 -88 requirements lead content should be less than 5 × 10 -7. With the progress of the times and the strengthening of environmental protection awareness, in order to overcome the secondary pollution caused by iron pipe to water sources, the state has decided to phase out the use of cast iron pipe and galvanized pipe in water supply