Floor Slip Resistance Testing Services

Certified Floor Coefficient of Friction (COF) Testing, in the Laboratory and in the Field

Sotter Engineering Corporation provides laboratory and field independent third-party floor slip resistance testing and road skid resistance testing services all over the USA and beyond. Our floor friction slip coefficient testing expertise is unmatched in the Americas, and our integrity is untouchable. Sotter Engineering Corporation provides specialized, certified, engineer-stamped floor, tile, and roadway dynamic coefficient of friction (DCOF) testing, ASTM E303 (updated in 2022) road and floor slip resistance testing, SCOF tile testing (ASTM C1028 and ANSI B101.1 – reliable in dry condition only), and we also sell floor floor friction test instruments (such as the pendulum DCOF tester and SlipAlert). Quick tile COF slip test turn-around in about 2-4 business days! Sotter Engineering is the tile slip coefficient testing experts! Get a tile COF test before installation and eliminate slips. Call or email John at 949-933-6971 to request a quote for field floor slip resistance testing, or with questions regarding floor slip resistance test standards. Prices quoted below are special “internet only” floor slip resistance testing prices, and are valid for tests ordered through our website without the need for us to fill out paperwork for your company. Additional charges may be required (at our discretion) if you need forms filled out by our technician.

Lab Floor Slip Resistance Testing Services

Recommended Floor Slip Resistance Test Package

ANSI A326.3 DCOF AcuTest AND an ASTM E303-22 Pendulum DCOF floor slip resistance test: $414.00 per sample. This lab slip resistance test package will give you two separate floor DCOF test reports – one for the latest test method written for the BOT-3000E (ANSI A326.3), which sets a very low bar, and another for the latest American floor slip resistance test (the newly revised ASTM E303-22 pendulum DCOF floor slip test), which we recommend the most for assessing the real-world safety of floors based on 50 years of peer-reviewed, international research in at least 50 nations.


Recommended Floor Slip Test Package PLUS Wear Test

OR, get the above tests PLUS our Sustainable Slip Resistance (wear) Pendulum Slip Test, which will give an indication of the slip resistance of your flooring before and after 1-2 years of use in a busy environment with lots of foot traffic. This is our most highly recommended option for high traffic areas. $495.00 per sample.


Floor Slip Resistance Tests

ASTM E 303-22 (2022 version) Pendulum DCOF Floor Slip Resistance Test or Road Skid Test – $230

Best dynamic coefficient of friction (DCOF) floor slip resistance test for measuring real-world coefficient of friction of both floors and the skid resistance of roads. Uses the pendulum tester, which has a published test method in over 50 nations. The ASTM E303-93 test was newly-revised in 2022. Safety criteria is based on 50 years of international research into real-world slip and falls. Our most recommended floor slip test method for reliable data.

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ANSI A326.3 DCOF Rating Test using the BOT-3000E or ANSI A137.1-2012 (aka “DCOF AcuTest”) – $230

According to the test method, this test is for “comparing surfaces”, not assessing slip risk. DCOF safety suggestions in this test method are easy to pass and written by people interested in helping sell slippery tile. Requires a 0.42 minimum DCOF for indoor level floors. Latest version gives minimums for other areas, too. Can give “passing” grades to very slippery floors. Do not rely solely on this test to assess safety.

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Pendulum DCOF Test using International Test Methods (Australia’s HB198, AS4586, AS4663, or Europe’s BS EN16165 or EN13036-4) – $230

Pendulum floor slip resistance testing using international standards such as the European pendulum test method EN 16165, Australian test method AS 4586, etc. Utilizes the most widely used slip resistance test device (tribometer) worldwide. Based on 50 years of real-world research in 50 nations.

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Sustainable Slip Resistance Pendulum Dynamic Coefficient of Friction (DCOF) Test – $320

Check whether the slip resistance of your flooring is acceptable both before and after significant wear by pedestrians and maintenance. For areas with high pedestrian traffic that must sustain its slip resistance over time.

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ASTM C 1028-07 SCOF Test – $290

Some specifiers still require it, but the results are meaningless in the wet condition. Obsolete, misleading test withdrawn by the ASTM in 2014. Not valid for assessing safety. Measures SCOF, which is irrelevant. Click the “Pay Now” button below to have this floor SCOF slip test done in our lab on your flooring sample.


ANSI/NFSI B101.3-2012 DCOF Test – $200

An expired U.S. standard using the BOT-3000E tribometer for indoor floors. Use A326.3 instead. The pendulum tribometer is much better for assessing safety because of decades of research behind it. Click the “Pay Now” button below to have this floor friction test done in our lab on your flooring sample.


ANSI/NFSI B101.1-2009 SCOF Test – $200

We do this floor slip test if required by a specifier, but it’s not a valid test for pedestrian safety, because it’s a static (SCOF) floor slip test. This is an expired test that can be helpful for dry areas only. Click the “Pay Now” button below to have this floor friction test done in our lab on your flooring sample.


SlipAlert DCOF Test – on-site floor slip resistance testing only – call for a quote

Qualitative demonstration that in most cases mimics pendulum readings. A simple, durable machine is used that requires minimal training. Email us to have this test done on your flooring on site. We can also sell you a SlipAlert (also known as iAlert now.)


Tortus Floor Friction Digital Tribometer DCOF Test – $230

Dry and wet slip resistance up to high values of coefficient of friction with hard or soft rubber. Endorsed by Ceramic Tile Institute of America since 2001. It appears in Australian floor slip resistance test standard. Click the “Pay Now” button below to have this test done in our lab on your flooring sample.



Click the button below if you’re using a United States credit card and want to pay for a Coefficient of Friction (Tile COF) Floor Slip Resistance Test:

Pay for slip resistance testInternational slip resistance testing clients will need to use a separate link to pay for testing services. Please add up what the charge is that you need to pay and then enter that amount on this page or enter the amount above the yellow button below.


If you also need to pay for a lab slip resistance test “rush fee” (an additional $75 per test for results in one business day), or if you need to pay for some field slip resistance testing at your location, or any other amount given to you by us for our services, you can enter the custom amount below and click on the yellow button to pay any amount necessary. Be sure to tell us what you’re paying for via email.
Amount: USD
If you’re sending a check, make it out to Sotter Engineering or Safety Direct America. Send your flooring or road samples for a slip resistance test, and your information to:
Sotter Engineering Corporation
c/o John C Sotter
26705 Loma Verde, Mission Viejo, CA 92691
Phone: 1(949)933-6971    E-mail: info@SafetyDirectAmerica.com
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Field Slip Resistance Testing of Floors and Roadway Surfaces

To have slip resistance testing for dynamic coefficient of friction (DCOF rating) done at your location, the charge will be based on time and expenses, or may be a fixed price, depending on the situation. 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 floors and roads, and slip resistance test reports come stamped by a registered professional engineer, usually within 3 business days of receiving your lab sample for slip testing. For more info, contact us by email or call (949)933-6971. Payment for field slip resistance testing (if we’ve already given you the price) can be paid for using the YELLOW “Pay Now” button above.

Sample Size Required For Slip Resistance Tests

Ideally, you will send a floor, tub or roadway sample 12″x12″ for slip resistance testing, but most slip tests can be done on smaller samples (for instance, a minimum of 5″x7″ for pendulum slip resistance tests, although bigger is better). Some test methods (ANSI A326.3, ASTM C1028-07) ask for three identical samples, but all tests can be done on one sample, if necessary. All tests above are done in the wet and the dry condition, except A326.3,  A1371.1, and B101.3…those test methods only call for wet testing (although we can do dry ANSI A326.3 dry testing for an extra $100 – pay using yellow “Pay Now” button above.) Here are some sample test reports: ASTM E303 Pendulum Slip Resistance Test Report, ANSI A137.1/A326.3, and Sustainable Slip Resistance (SSR) Pendulum Test. Using decades of research from around the world, we can now use ASTM E303-22 pendulum test results to guide in the assessment of real-world slip resistance using the safety criteria used in the United Kingdom, Europe, Australia, New Zealand, and elsewhere.

Floor Slip Resistance Testing Experts

Rush Fee and Other Common Slip Resistance Test Questions

RUSH/EXPEDITE: If you need your floor slip resistance tests expedited, we can usually get your flooring or roadway surface tested and a report sent to you within one business day (with rare exceptions) of receiving your sample for an extra $75 (expediting fee per test). Pay that fee here by entering “75” (per test) above the yellow “Pay Now” button. Contact us by email to make sure that we’ll be able to handle your request.

If MULTIPLE TESTS are ordered on one sample at the same time, a 10% discount applies to the test total charge. Test samples are stored for 21 days before being discarded. If you’d like your slip resistance test SAMPLES RETURNED, please let us know promptly. There is minimum $25 fee (plus the cost of shipping if you don’t have an account number we can use) for the return of a sample. This charge could be more based on individual circumstances. Preferably, you can include a return shipping label with your shipment to us, which will help keep this charge low.

We have field slip resistance testing clients from Bermuda to Japan to Guam, Mexico to Canada, New York City to Seattle, and throughout the entire USA. 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. Periodic slip resistance testing (or traction auditing) of your floor’s slip-resistance has many potentially multi-million dollar cost-saving benefits for building owners and safety mangers. We can test dry only for areas that stay dry in use; and dry and wet for areas that get wet in use. (We can also help you if you’d like to buy your own slip resistance test instrument.) Here’s more detail on our slip resistance testing.

Some Floor Friction Tests We Don’t Do and Why

Some clients are looking for an “R Rating” for their flooring, which involves the German Ramp Test, or DIN 51130. A human subject wearing “work boots” walks up and down a ramp with a a particular flooring sample on it, and the floor is covered in motor oil. R9, R10, R11, R12, and R13 are the available classifications, R9 being the most slippery flooring. This floor slippage test is very expensive, can only be done in a lab, and it isn’t testing typical pedestrian conditions like the British Pendulum Tester, which uses water and standard shoe sole simulating rubber. Here is more discussion on the German Ramp Test for Floor Slip Resistance.
ASTM D2047 (and UL 410, which uses the same test method) amounts to nothing less than fraud when it comes to claiming that this test using the James Machine is reliable for assessing a floor’s slip resistance. ASTM D2047 is a static test (SCOF), which is measuring whether the floor is slippery to someone who is standing still (static) on it, and the floor is tested in the clean and dry condition. There has never been a slip and fall accident in the history of humankind in these conditions.
The English XL and Brungraber Mark II and Mark IIIB tribometers are popular amongst expert “liars for hire” in the USA who work exclusively for lawyers. The “experts” who use these devices are great at (miraculously) getting exactly the answer their lawyer client wants them to get each and every time they’re called to “test” a floor. Both the English XL and Brungraber Mark II were rejected many years ago by both the ASTM and OSHA. The Brungraber Mark IIIB appears to be just a shinier version of the Brungraber Mark II. All three of these instruments have a published, peer-reviewed test method for their use in exactly zero nations on earth. They lack precision.

Reliable Floor Slip Resistance Testing/Floor Friction Testing From Sotter Engineering Corporation

The pendulum test is easily the world’s most reliable floor friction test for assessing the real-world slip resistance of flooring, as it can test for the dynamic coefficient of friction (DCOF) both in the lab and after the flooring has been installed and maintained, which is often crucial to avoiding slips on your property. It’s based on over 50 years of research around the world, and uses distilled water as the lubricant and standardized shoe rubber as the slider, which mimics real-world conditions.

Send your flooring samples for slip resistance testing to:

Sotter Engineering Corporation
c/o John C Sotter
26705 Loma Verde, Mission Viejo, CA 92691