Floor Slip Resistance Testing Services

Certified Coefficient of Friction (COF) Testing for Roads and Floors, in the Laboratory and the Field

Safety Direct America/Sotter Engineering 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. We provide specialized, certified, engineer-stamped floor, tile, and roadway dynamic coefficient of friction (DCOF) testing, ASTM E303-22 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 COF tile slip test turn-around in about 3 days! We’re the tile slip coefficient testing experts! Get a COF tile 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

Lab Floor Slip Resistance Testing Services

Recommended Floor Slip Resistance Test Package

ANSI A326.3 and an ASTM E303-22 Pendulum DCOF slip test: $387.00 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 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) Test, which will give an indication of the slip resistance of your flooring after 1-2 years of use in a busy environment with lots of foot traffic. This is our most highly recommended option. $457.00 per sample.


Floor Slip Resistance Tests

ASTM E 303-22 Floor Slip Resistance Test or Road Skid Resistance 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. Th3 ASTM E303-93 (2022) 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 or ANSI A137.1 (aka “DCOF AcuTest”) – $200

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 (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, Australian test method, 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 DCOF Test – $320

Check whether the slip resistance of your flooring survives 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 B101.3 DCOF Test – $2

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 B101.1 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 (e-mail address, company name, name of the test sample, etc.), to:
Safety Direct America
c/o John C Sotter
26705 Loma Verde, Mission Viejo, CA 92691
Phone: 1(949)933-6971    E-mail: info@SafetyDirectAmerica.com
Contact Us

Field Slip Resistance Testing of Floors and Roadway Surfaces

To have slip resistance testing for dynamic coefficient of friction (DCOF rating) 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 $50 – 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 assess 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. If ten or more tests are ordered and paid for in the same calendar year, every tenth test will be at no charge. TURNAROUND TIME for laboratory slip resistance tests is usually around 3 business days. 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 of a $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.

Testing Floors for an “R Rating” using DIN 51130

Some clients are looking for an “R Rating” for their flooring. That involves the German Ramp Test, or DIN 51130, which is where a human subject wearing “work boots” (and who is attached to a safety harness) walks up and down a ramp with a a particular flooring sample on it, and the floor is covered in motor oil. The angle of the ramp is increased steadily until the subject slips, and then the angle at which the ramp was when the slip occurred is converted into an “R Rating” for the flooring. R9, R10, R11, R12, and R13 are the available classifications, R9 being the most slippery flooring, and R13 being reserved for flooring with very low slip potential. The test is a very expensive test that can only be done in a lab (usually in Germany or Australia), and it isn’t testing typical pedestrian conditions like the British Pendulum Tester. Here is more discussion on the German Ramp Test for Floor Slip Resistance, which includes some research that has been done comparing pendulum test values to German Ramp Test DIN 51130 values.

Fraudulently Testing Floors using ASTM D2047, the English XL and Brungraber Mark IIIB

ASTM D2047 (and UL 410, which uses the same test method) amounts to nothing less than fraud when it comes to claiming that these tests are reliable slip resistance tests for flooring. D2047 is the “Standard Test Method for Static Coefficient of Friction of Polish-Coated Flooring Surfaces as Measured by the James Machine”. This means that ASTM D2047 is a static test (SCOF), which is measuring whether the floor is slippery to someone who is standing still (static) on it, not walking on it. The test is done with a leather slider (supposedly only on polish-coated floors), with the flooring sample in the clean and dry condition. So it’s measuring if a floor is slippery when the floor is clean and dry and a person is just standing there on it. There has never been a slip and fall accident in the history of humankind in these conditions, and anyone trying to sell you flooring claiming their flooring has “passed” this test is either profoundly ignorant as to what constitutes a valid floor slip resistance test, or they are purposefully lying to you about the “safety” of their flooring. Either way, this is not science. At all.
The English XL and Brungraber Mark II tribometers are popular amongst expert “liars for hire” in the USA who work exclusively for lawyers. The “experts” who use these devices know they need to get certain answers in each case to either further or defend multi-million dollar slip and fall lawsuits. Both of these devices were rejected many years ago by both the ASTM and OSHA. They are not scientific devices and they lack precision, which means they are great for “expert court liars” who can manipulate the machines to get the answer they need to make a lawyer happy, which will keep their lawyer friends calling for a “test” each time they get a slip and fall victim in their law office. The Mark IIIB is just a shinier version of the Mark II. Again, these instruments were both rejected by both the ASTM and OSHA, and they have a published, peer-reviewed test method for their use in exactly zero nations on earth for that reason. The fact that judges allow these “instruments” in American courtrooms (and ONLY in American courtrooms) is enough to make one’s blood boil. Don’t be fooled by their fancy suits and claims that ASTM F2508 “validates” their instrument. (See previously mentioned blog post.) These are lies meant for courtrooms.

Reliable Floor Slip Resistance Testing/Floor Friction Testing

The pendulum test is easily the world’s most reliable test for assessing the slip resistance of floors, as it can test for the dynamic coefficient of friction (or slip resistance) 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 50 years of research around the world, and uses distilled water as the lubricant, which mimics real-world conditions much better than the ramp test. The DIN 51130 German Ramp test can only tell you how slip resistant a floor is when you first pull a tile out of the box, and how slippery it is to someone wearing work boots on a floor covered in motor oil. ASTM D2047, ASTM F1677 (for the Brungraber Mark II) and ASTM F1679 (for the English XL) are meant to fool flooring consumers and courtroom slip and fall lawsuit juries. If you’re looking for the truth, those tests will disappoint.

Send your flooring samples for slip resistance testing to:

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