SlipNOT®products help business owners meet the legal requirements to provide a safe working environment for employees - unlike traditional metal floor covering. Coefficient of friction tests conducted for the City of Los Angeles revealed that "Diamond" or "Checker" plate surfaces "provide inadequate slip resistance, particularly
when wet or worn" according to an article by Jeffery S. Robertson dated May, 1984 that appeared in Professional Safety, the official publication of the American Society of Safety Engineers. The article also states, "when worn, these plates actually become slippery to the point of being
dangerously unsafe. Adding water, dust or road film to this type of vault cover creates a potentially critical problem in public safety."