ASTM D570

WATER ABSORPTION OF PLASTICS

This test method covers the determination of the relative rate of absorption of water by plastics when immersed. This test method is intended to apply to the testing of all types of plastics, including cast, hot-molded, and cold-molded resinous products, and both homogeneous and laminated plastics in rod and tube form and in sheets 0.13 mm [0.005 in.] or greater in thickness.
Source: www.astm.org