Appendix 3
Standard Sands for the Abrasives Industry

A.G.A. Bonded Standard Sands

Because of the difficulty in purchasing consistent, performance tested sieves, the Abrasive Grain Association (now United Abrasives Manufacturers Associated) Standards Committee decided to adopt a series of standard testing minerals composed of medium shaped Brown Aluminum Oxide (most common abrasive used in the industry). These sands were to be available industry wide for performance testing Rotap sieves.Washington Mills volunteered to maintain supplies of these standards for use as a checking mineral. Sands are available for U. S. Std. sieves No. 4 through 325. The sands are specially formulated to retain a constant percentage on the sieve being tested. A master set of sieves is used to validate the test and ensure that results are the same as the original standard sands.

C.A.M.I. Standard Sands

Originally The Carborundum Company, in conjunction with the Coated Abrasives Manufacturers Institute, developed standard sands for testing Coated abrasives. They are standard grits (12 through 220) composed of garnet. The grits are used to qualify sieves for testing garnet, aluminum oxide, silicon carbide or zirconia-alumina grains. Washington Mills continues to supply these standards to the industry.

FEPA P Standard Sands

These are standard grits supplied by Staatliche Materialprufangstalt, Darmstadt, Germany for qualifying sieves to use for testing FEPA P Coated abrasives. They are brown aluminum oxide grits P12 through P220. Darmstadt has supplied these sands to the industry for testing the European grade of Coated abrasives for many years. Darmstadt has advised that only standard grits dated 2001 or later should be used, since those produced before that date were checked on an older set of sieves and are no longer considered to be accurate.