Misleading ASTM C 1028 Friction Test Continues to Wreak Havoc in the USA
Misguided investments of hundreds of millions of dollars in slippery flooring … pain, suffering, and financial losses to accident victims and their families … lawsuits by the thousands … and lack of consumer confidence in ceramic tile and other hard flooring: these are some of the consequences of a poorly-conceived floor “slip-resistance” test — ASTM C1028, Static Coefficient of Friction, published and sold by the American Society for Testing and Materials. Floor safety experts in most developed countries have considered this test method to be a joke for many years.
Conceived decades ago as a simple way of testing static friction and giving passing grades to many visually attractive but hazardous slippery floors, ASTM C1028 survives despite the availability of far better test methods. No surprise, because lots of people profit from slippery floors: physicians and hospitals, physical therapists, lawyers, and expert witnesses, to name a few. Slip-and-fall accident victims and the disabled are often mystified as to how so many slippery floors (especially wet ones) came to exist and to dramatically change their lives in an instant.
The ASTM C1028 SCOF test measures the amount of force needed to overcome friction of a 50-pound stationary object, barely coaxing that object briefly into motion. The problem is, most people aren’t standing still when they slip and fall — they’re moving. This means that what’s relevant is dynamic, not static, friction. Test methods such as ANSI A137.1 (using the BOT-3000E tribometer, and now part of the International Building Code used in most U.S. jurisdictions and a number of other countries), and the pendulum and Tortus instruments endorsed by Ceramic Tile Institute of America (CTIOA), measure dynamic friction and correlate with pedestrian safety. The pendulum is a national standard for pedestrian friction in at least 49 nations and has been endorsed by CTIOA since 2001.
The Access Board of the U.S. Department of Justice issued a document in 1992 that was taken by many as an endorsement of ASTM C1028. A static coefficient of friction of 0.60 or higher seemed to appear safe for level floors, and 0.80 or higher for pedestrian ramps.
The Access Board long ago denied any support for, or confidence in, static friction. But like a vampire that keeps coming back, C1028 is still used by many architects, designers and building owners as their only criterion to try to prevent them from successfully being sued because of a slippery floor. It doesn’t necessarily work, because all competent U.S. slip-and-fall forensic experts acknowledge that static friction is not adequate to prevent accidents. For more information on ASTM C 1028, please see www.C1028.info.
Safety Direct America conducts laboratory and field coefficient of friction tests using ANSI A137.1, two other relevant ANSI tests, the pendulum, and the Tortus. For those who insist on ASTM C1028 we conduct that test too — but we do not recommend using it as your sole criterion for slip-and-fall safety.
If you want to prevent slips on your property, contact George Sotter at Safety Direct America, 1-800-988-6721, for our recommendations. We’re consultants to two major cruise ship companies as well as property owners, insurance companies, and attorneys. We wrote the book on slip prevention — see STOP Slip and Fall Accidents! at amazon.com. Have a safe day!