Skid Resistance Scale for Tile Flooring
Coefficient of Friction: Wet/Dry
The skid resistance scale is used to determine the degree of slippage on a tiled surface. While
assessing different tile surfaces, wet and dry conditions along with the speed of the subject are
monitored. Also, the required force to move that subject and the angle of the tiled place are
considered too. The Ceramic Tile Institute identifies tile in the following three categories:
-
Slip Resistant: Coefficient of friction is 0.60 or greater (wet). Meets or exceeds
general safety and health regulations, ADA and OSHA requirements.
-
Conditionally Slip Resistant: Coefficient of friction is 0.50 to 0.59 (wet). Meets or
exceed general safety and health regulations and OSHA requirements.
-
Questionable: Coefficient of friction less than 0.50
One important fact is that the more textured a tile is, the less slippery it is. And that�s why,
polished or highly polished tiles are not recommended for high traffic areas or for residential
sites with children and the elderly. Also, as a rule the greater the anti-slip finish on the tile, the
harder it is to keep clean.
The DIN classification for tile slippage
DIN, the German Institute for Standardization classifies tile slippage within the DIN 51130 set.
In this set, the various working areas are classified in five groups, according to the degree of
slippage. To determine in which of these groups a material should be classified, it is applied on a
surface that is gradually sloped. A person wearing shoes walks up and down the slope until he
starts slipping. The value in degrees of the slope reached before he starts slipping determines the
classification of the material in class. Here are the ratings:
Rating R9
Suitable for a less than 10% slope (minimal friction)
Rating R10
Suitable for a 10 to 19% slope (normal friction)
Rating R11
Suitable for a 19 to 27% slope (normal friction)
Rating R12
Suitable for a 27 to 35% slope (high friction)
Rating R13
Suitable for slopes more than 35% (very high friction)
Also, another set DIN 51097 classifies tiles from A to C for non-slip suitability, but this time for
foot traffic in wet areas:
Rating A
Suitable for a slope up to 12%
Rating B
Suitable for a slope up to 18%
Rating C
Suitable for a slope up to 24%
There is also the Pendulum Skid Resistance Test, which also gives following ratings for tiles:
Rating 35-65
Good skid resistance
Rating 66+
Excellent skid resistance