Laboratory and Field Floor Slip Resistance (Coefficient of Friction) Testing      

Sotter Engineering Corporation provides specialized floor friction, coefficient of friction, and Sustainable Slip Resistance testing services and instruments, both for the laboratory and in the field. We offer not only one-time field tests, but the option of periodic monitoring (quarterly, annually, etc.), which includes testing dry only for areas that stay dry in use; and dry and wet for areas that get wet in use. Our monitoring and our floor maintenance recommendations based on test data from your floors can drastically reduce your expenditures for slip-and-fall claims in areas with heavy foot traffic. Periodic monitoring of your floor's slip-resistance has many potentially multi-million dollar cost-saving benefits for building owners and safety mangers. We are approved by the City of Los Angeles (one of the few government agencies in the USA that has an approval process) for testing slip resistance of flooring. (If you'd like to buy your own slip resistance tester, click here.) We can test using the following methods:

Static Coefficient of Friction (SCOF):

  • Horizontal dynamometer pull-meter (ASTM Method C1028-07)  We conduct this test but do not offer the apparatus for sale. ASTM, Ceramic Tile Institute of America, Tile Council of North America, University of California Medical Center and Safety Direct America do NOT recommend this method as a primary means of assessing floor slip resistance. [ASTM standards rules allow only test devices that do not involve patented or proprietary
    technology. For this reason the best test methods for floor friction, except for the pendulum, are not and can not be specified by ASTM standards.] Laboratory slip-resistance tests for floor SCOF are $230, which includes a written     report signed and stamped by a California-licensed Professional Engineer. Field test prices are based on time and travel expenses for our technician. Contact George Sotter for a quote.

Dynamic Coefficient of Friction (DCOF):

Laboratory slip-resistance tests for floor DCOF are $230, which includes a report signed and stamped by a California-licensed Professional Engineer. Field test prices are based on time and travel expenses for our technician. Please contact George Sotter for a quote. We can test slip resistance using these four test methods and instruments:

  • Tortus with Four-S (hard) and/or TRRL (soft) rubber slider

  • British Pendulum (adapted for floors from ASTM Method E 303) with Four-S and/or TRRL rubber slider; and EN 13036-4 with CEN rubber slider. The pendulum is used for our highly recommended Sustainable Slip Resistance test, which is $290.

  • SlipAlert floor slipperiness indicator

  • BOT-3000 Binary Output Tribometer with Neolite, SBR, Four S, TRL or hosiery sliders. Can measure COF up to 1.00. We can test using the ANSI B101.1 and B101.3 methods with the BOT-3000.

Peak-to-valley surface roughness:

  • Taylor-Hobson Surtronic 10 profilometer


Normally three pieces of flooring are considered one sample. This allows for variation between pieces. Laboratory tests usually have a turnaround time of 2-4 business days. Please contact us for prices.


Ceramic Tile Institute of America endorses the Tortus and the Pendulum.  In a study of nine types of tribometers at the University of Southern California Medical Center in which slip-and-fall experts from around the world participated, the Tortus received the highest rating; click here for details.  SlipAlert has had very favorable reviews from British and Australian government safety research agencies. The static coefficient of friction method ASTM C 1028 is principally used for manufacturing quality control purposes rather than assessing slip resistance, but is sometimes specified as an indicator of slip resistance. We recommend using the Tortus or pendulum test instead, as these are more reliable and are recommended for slip resistance by Ceramic Tile Institute of America.


Horizontal dynamometer pull-meter (ASTM Method C 1028-07):

 

 

Click on the photo below to see VIDEO OF THE TORTUS IN ACTION (80 seconds):

 

 

Click on the photo below to see VIDEO OF THE PENDULUM IN ACTION (80 seconds):


 

The pendulum flies from right to left, sweeping out a five-inch-long path where its three-inch-wide slider contacts the floor


 

Click on either of the two photos below to see VIDEO OF SLIPALERT IN ACTION (50 seconds):

SlipAlert’s 1 3/4-inch slider contacts floor on its trailing edge while rolling of front wheels adds negligible friction:


BOT-3000 Binary Output Tribometer can measure both static and dynamic friction, and with "smart" sensors is the latest in floor friction technology (click on the photo below for a 2 minute VIDEO DEMONSTRATION)