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

and ASTM E303 Road Skid Resistance Testing

Our floor slip resistance testing equipment and expertise is unmatched in the Americas. Sotter Engineering Corporation provides specialized floor slip resistance/coefficient of friction and Sustainable Slip Resistance testing services and instruments, both for the laboratory and in the field. We have slip resistance testing clients from Florida to New York to Hawaii to Canada, and are based in the Los Angeles area. To have your floor slip resistance tested at your location, the charge is based on time and expenses - contact George at (949)582-0889 for a quote. We offer not only a one-time field slip resistance tests, but the option of periodic slip resistance monitoring (quarterly, annually, etc.) of the coefficient of friction of your floors. We can test dry only for areas that stay dry in use; and dry and wet for areas that get wet in use.

We are certified 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, and reports come stamped by a registered professional engineer. (We can also help you if you'd like to buy your own slip resistance tester.) Watch our video on Slip Testing at the bottom of the page.

Send your flooring samples for a slip test and your information (including what test you'd like, your name, email address and company name, name of the test sample, and a check [made out to Safety Direct America]) to:
George Sotter
26705 Loma Verde, Mission Viejo, CA 92691
Phone: 1(949)582-0889    E-mail:
Or you can pay by credit card by clicking the orange "Buy Now" button below to pay for any of our slip resistance tests, then just send us the samples and your information:
Floor Slip Resistance (COF) Lab Test
Charge per Sample
Why do this test?
ANSI A137.1 (aka "AcuTest") DCOF Test$179Specified in 2012 International Building Code. Easier to pass than ANSI B101.3, a similar test.Similar to ANSI B101.3 but easier to pass due to lower detergent in wetting solution.
ANSI B101.1 SCOF Test$179
If required by specifier. Not a valid test for pedestrian safety, because it's a static test. Made obsolete by ANSI B101.3, a dynamic test.
ANSI B101.3 DCOF Test $179
A recent U.S. standard using the BOT-3000E digital tribometer, mostly indoors. Based on extensive research.Pendulum is more appropriate for outdoor surfaces because of its higher speed.
ASTM C 1028-07 SCOF Test
Some specifiers still require it.
Obsolete, misleading test due for withdrawal by ASTM. Not valid for assessing pedestrian safety. 
ASTM E 303 Road Skid Test$179
An American skid test for road surfaces.
A simplified pendulum test with soft TRL rubber.
Pendulum DCOF Test (CTIOA or EN 13036-4)$230
Dry and wet slip resistance appropriate to various conditions, e.g. pool deck, lobby, rest room, etc.
The most widely used slip resistance tests worldwide. Endorsed by CTIOA since 2001.
Slip Alert DCOF TestOn-site only
Qualitative demonstration that in some cases mimics pendulum readings.
A simple, durable machine is used that requires minimal training.
Sustainable Slip Resistance Pendulum DCOF Test$290
Check whether slip resistance survives after significant abrasive wear by pedestrians.
For areas with high pedestrian traffic that must remain slip resistant.
Tortus Digital Tribometer DCOF Test $230Dry and wet slip resistance up to high values of coefficient of friction with hard or soft rubber.CTIOA endorsed since 2001.

Pay for a Floor Slip Resistance (Coefficient of Friction) Test

Most tests require at least one flooring sample of at least 10"x10".
Sending three samples of each flooring type you'd like tested is ideal, as some tests require three independent pieces (this allows for variation between pieces). For pendulum testing, the samples must be at least 5"x7", and the Tortus Tribometer can measure anything down to 1"x1", but bigger is always better (12"x12" is ideal). All tests above are done in the wet and the dry condition, except A137.1, B101.3 and E303...those test methods only call for wet testing (although we can do ANSI A137.1 testing dry by request.) If multiple tests are ordered on one sample at the same time, a 10% discount applies to the test total charge. If ten or more tests are ordered and paid for in the same calendar year, every tenth test will be at no charge. Laboratory slip resistance tests usually have a turnaround time of 2-3 business days.

Our slip-resistance test monitoring and floor maintenance recommendations based on slip-resistance test data from your floors can drastically reduce your expenditures for slip-and-fall claims in areas with heavy foot traffic. Periodic slip resistance monitoring (or traction auditing) of your floor's slip-resistance has many potentially multi-million dollar cost-saving benefits for building owners and safety mangers.
Here's more detail on our slip resistance testing:

Dynamic Coefficient of Friction (DCOF):

We can run slip resistance tests using these four test methods and instruments, all of which measure dynamic coefficient of friction:

  • BOT-3000E Binary Output Tribometer with Neolite, SBR, Four S, TRL, leather or hosiery sliders. Can measure COF up to 1.00. We can test using the ANSI B101.3 (dynamic coefficient of friction) and ANSI B101.1 (static coefficient of friction) methods with the BOT-3000, as well as the new ANSI A137.1 dynamic coefficient of friction (DCOF) AcuTestSM that is now part of the current International Building Code.

  • 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. We can also run an ASTM E-303 test for road skid resistance with the British Pendulum.

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

  • SlipAlert floor slipperiness indicator

Peak-to-valley surface roughness:

  • Taylor-Hobson Surtronic 10 profilometer

Static Coefficient of Friction (SCOF):

  • Horizontal dynamometer pull-meter (ASTM Method C1028-07): Laboratory floor slip-resistance tests for SCOF includes a written report signed and stamped by a California-licensed Professional Engineer.  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 (or any wet static coefficient of friction test) 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.] We can also run the ANSI B101.1 static COF test, if required. Field slip resistance test prices are based on time and travel expenses for our technician. Contact George Sotter for a quote.

We presently do floor slip resistance testing both on-site and/or in our laboratory for two major cruise ship companies, Outrigger Reef on the Beach in Waikiki, Exeter Hospital in New Hampshire, the Ceramic Tile Institute of America, attorneys representing both plaintiffs and defendants, the Cities of New York, San Francisco and Los Angeles, Cartier, The Montage Resort and Spa, Crowne Plaza Hotels, Intel, and many other major international companies all over the USA.

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 on the slip-tester test.  SlipAlert has had very favorable reviews from British and Australian government safety research agencies. The static coefficient of friction method ASTM C1028 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 slip resistance test instead, as these are more reliable and are recommended for slip resistance testing by Ceramic Tile Institute of America. We also recommend the BOT-3000E as it has an ANSI test method (B101.3 dynamic coefficient of friction test) and safety standards for wet slip resistance testing.


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

Click on the photo below to see a
video of the TORTUS in action (80 seconds):

Click on the photo below to see
video of the PENDULUM in action (80 sec.):

Click on the photo below to see
video of SLIPALERT in action (50 sec.): 

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


Slip Resistance Test Methods Video

Send your flooring samples for slip resistance testing and your information (including what test you'd like, your name, email address and company name, name of the test sample, and a check [or call us with your credit card info]) to:
George Sotter
26705 Loma Verde
Mission Viejo, CA 92691
Phone: 1(949)582-0889