In many commercial situations (restaurants, outdoor malls, lobbies, restrooms, etc.) it’s necessary not only that the flooring be slip-resistant when wet, but that it remain slip-resistant for years under high foot traffic. This is known as Sustainable Slip Resistance (SSR).
McDonalds Restaurant chain discovered that when they installed slip-resistant flooring in the customer areas of their restaurants, often the slip resistance faded after a few weeks or months because of wear. So they spent several years developing a test for Sustainable Slip resistance, finally adopting it as a specification for new flooring.
Under the McDonalds spec, flooring is first tested for wet slip resistance using the pendulum tester. Then it is abraded using a standard three-inch-square abrasive pad under 2.2 pounds (1 kilogram) of load. Finally, it is tested wet again with the pendulum tester. For a level floor, McDonalds requires that the wet Pendulum Test Value be 35 or higher.
This test has since been adopted by two major cruise ship companies, and by property owners such as Westfield, Toyota, Aldi Supermarkets and Stockland.
You can have tile and stone laboratory-tested by Safety Direct America using the SSR test. The charge is $320 per sample. We can also recommend a number of types of tile and stone that have already passed this test.