Slip resistance - Coefficient of Friction (COF)

In terms of shoes, slip resistance is the amount of resistance the sole of the shoe exerts while moving over a particular walking surface. This is measured on a scale based on the Coefficient of Friction (COF). This scale starts from 0.00, comparable to ice, oil or a similar slippery surface and goes up to 1.00, which is like walking on a dry carpet. Industry experts consider a reading of 0.40 to be the benchmark for a shoe providing above-average slip-resistant qualities.

This is not just important for people working in special environments but a major consideration for all of us. At kybun this has always been a significant factor in our research and development. The inventor of kybun Karl Müller has consistently talked about the slip-resistant qualities of the kybun soles and this new test* on a kybun sole backs up this claim with impressive results under controlled laboratory conditions.

The following tests were conducted on the kybun sole using a standard red quarry satra tile (combined test results):

Backward Forepart Slip


Forward Heel Slip


COF Scale

0.00   1.00

*These tests (according to ASTM F2913-19 Standards) were undertaken by Precision Testing Laboratories USA, an independent and renowned international company in the field of textile tests.

How dangerous are slippery surfaces?

Particularly in the winter months, the risk of falling for people on foot is greatly increased. One in four tripping or tumbling accidents occurs on account of the weather.  Most of the time, these accidents involve ice or frozen surfaces, and around 12,000 people are injured in these incidents every year.

    Tips to help avoid accidents:

    • Choose suitable footwear outdoors as well as indoors.
    • Always allow enough time for your journey.
    • Keep fit with balance exercises as well as strength, endurance and flexibility training.
    • From the age of 50, practice balancing in daily routines, e.g. brushing your teeth on one foot
    • Use snow- and ice-free paths whenever possible.