What is ASTM?

 Yesterday I came across a piece of PVC pipe brought by the plumber who told me that it is ASTM. That prompted a Google search as usual and I could find a bit about ASTM International. ASTM International was formerly known as American Society for Testing and Materials, till they changed their name officially in 2001. That PVC pipe actually showed ASTM D-1785, which is a specification for pressure pipes used in plumbing. Another abbreviation noted on the same piece of pipe was PVC-U which stands for Poly Vinyl Chloride - Un-plasticised.



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