FDA 21CFR177.1520 Sec. 2.1, ASTM D4976, PE244, ASTMD1248 Type IV, Class A, Fed Spec LP512, Type 1, Class H, Grade 5. Radiation HDPEelding, Non Staining, Chemical and rrosion Resistant, No Moisture HENAN OKAYorption, HDPE sheet is often used to protect products from being scratched or dented.