and ADA Recommendations on COF
(Exerts from Public Law 101-336)
Safety and Health Administration (OSHA)
that all walkway surfaces shall be maintained in a non-slip condition.
Steps with non-slip surfaces shall be provided; floors, footwalks, and
passageways in the work area around machines or other places where a
person is required to stand, or walk, shall be provided with an
effective means to minimize slipping. A static coefficient of friction
of .50 or above is considered a safe walkway surface with a dry
condition. A reading below .50 is considered an unsafe surface.
with Disabilities Act (ADA)
states that ground and floor surfaces along accessible routes and in
accessible rooms and spaces including floors, walks, stairs and curb
ramps, shall be firm, stable and slip resistant.
The ADA sponsored a research project to conduct test with persons with
disabilities and concluded that such persons needed a higher coefficient
of friction. A static coefficient of friction of .60 is recommended for
of Friction (COF)
is the measurement of slipperiness on a surface. When testing the
surface, a rubber-soled shoe with a weight is pulled across a surface
while measuring the amount of force required to pull it across (Static
Coefficient). As may be expected, dry rubber soles on a dry surface have
the highest coefficient of friction. For example, on a dry untreated
Gloss Ceramic Tile, dry rubber has a COF of approx. .90 - .95. When the
tile becomes wet from mopping or spills, the COF drops to .40 - .45.
This is below minimum safety standards.