ASTM C217
Standard Test Method for Weather Resistance of Slate - This test method covers two procedures for weather resistance of slate in all outdoor installations by determining the depth of softening by shear/scratch tester or by hand scraping.
Standard Test Method for Weather Resistance of Slate - This test method covers two procedures for weather resistance of slate in all outdoor installations by determining the depth of softening by shear/scratch tester or by hand scraping.
