A few years ago Sotter Engineering Corporation’s Safety Direct America (SDA) floor slip resistance testing laboratory participated in a global interlaboratory program that showed SDA to be one of the world’s three most accurate labs in use of the pendulum floor slip resistance tester. The pendulum is a national standard for pedestrian floor and tile dynamic coefficient of friction (DCOF) slip resistance testing in at least 50 nations and is the most used pedestrian slip test method worldwide. It’s been in continual use for over 50 years now.
In that 2018 study, 39 laboratories in eight nations participated. The program was supervised by Carl Strautins of Safe Environments in Australia. Testing included five different flooring surfaces: three ceramic tiles and two abrasive films. Both hard and soft rubber test sliders were used, and all of the surfaces were tested wet for DCOF.
In 2022, Mr. Strautins then conducted a follow-up floor slip resistance testing program in which 20 laboratories participated. [In the new study’s results [(Proficiency Testing Report No. 26833, Safe Environments), SDA is identified as Lab K.] Two types of surfaces, two specific commercially-available ceramic tiles (one black and one gray), were used. For the study, these tiles were distributed to the labs for wet DCOF testing using the pendulum tribometer, using only the Slider 96 hard slider, which mimics standard shoe soles.
Statistical analysis of the results indicated that the wet Slip Resistance Value (or Pendulum Test Value) was approximately 20.3 for the black tile, with a maximum permissible error of 2; and 40.6 for the gray tile, with a maximum permissible error of 2.5.
Results submitted by the 20 labs were classified as “satisfactory performance,” “questionable performance,” and “unsatisfactory performance.” For both tested surfaces, Safety Direct America’s test results were well within the limits for satisfactory performance. This again provides reassuring proof that SDA’s floor slip resistance testing lab provides accurate data for pendulum floor slip tests.
Only one lab of the twenty participating labs had one result that was in the “unsatisfactory” category, which proves that the pendulum device has reproducibility and precision between labs, which is required for all sound scientific devices. The English XL (VIT) and Brungraber Mark II (PIAST) tribometers were not able to show that they had reasonable precision, which is why ASTM F1677 and ASTM F1679 were withdrawn by the ASTM in 2006. These instruments get wildly different answers on identical tiles depending on whether the user is working for the plaintiff or the defense in a big-money slip and fall lawsuit. Those instruments are therefore not considered valid scientific tribometers. Unfortunately, they are too often still allowed in American courtrooms where expert liars present bogus data to help win lawsuits using unproven, easily-manipulated instruments.
The BOT-3000E can also get wildly unreliable readings on many polished floors, which is why the latest test method, the Tile Council of America’s (TCNA) ANSI A326.3, clearly states that “it can provide a useful comparison of surfaces, but does not predict the likelihood a person will or will not slip on a hard surface flooring material.”
Unfortunately, the TCNA has proven over the decades that it works to help tile and flooring manufacturers sell slippery products with test methods that say almost all floors aren’t slippery, and their tests have never been based on any good science or research. They promoted ASTM C1028 before it was withdrawn, and then created ANSI A326.3 to fill the void left when that horribly misleading SCOF test needed to go away because it was so dangerous and was sending so many American to emergency rooms.
The most significant and useful pendulum test (and floor slip resistance test) in the world today is the Sustainable Slip Resistance (SSR) test. Initial wet slip resistance is first measured with the pendulum DCOF tester. Then the sample is abraded for 500 cycles with a standard abrasive pad uniformly loaded with 1 kg to mimic 1-2 years of heavy foot traffic on the flooring. A second wet pendulum test then shows how much the slip resistance has changed due to abrasion (or simulated wear of the flooring sample).
This is the most significant test because the value of a flooring to the buyer depends not only on the initial slip resistance, but the slip resistance after an economically reasonable life span. McDonald’s Restaurants in Australia, for example, has specified that the sample must have a wet Pendulum Test Value of 35 or more after abrasion before they install it in their restaurants. Otherwise, it has been found that an initially slip-resistant flooring can have become slippery wet after only a few weeks in a busy fast-food restaurant. A floor that doesn’t maintain it’s slip resistance over time is a floor that will need to be replaced often, costing the building owner unnecessary expenses.
The 2022 study by Strautins and Plucinski published on May 5, 2023 has analyzed results from the SSR test. Only five labs participated this time. Two samples were tested at each slip resistance test lab.
The test results after analysis indicated that Safety Direct America reported the most accurate results of the five, as indicated by Z scores. Therefore, we can conclude that Sotter Engineering Corporation’s Safety Direct America floor slip resistance test lab is the world’s top lab for accuracy in the world’s most important and informative floor slip resistance test.
If you need your flooring assessed for slip resistance, we conduct testing in our lab and around North America and beyond. We don’t specialize in lying in court when your floor has caused an avoidable injury to an innocent pedestrian, but we specialize in providing reliable and accurate slip resistance test data to help building owners and architects make informed decisions and avoid slip and fall accidents on their properties.
Our “recommended slip test plus wear package” includes both the ANSI A326.3 test (because so many people have been fooled into believing that it’s the “latest, greatest American test” and those results are too often needed to show to misinformed building inspectors), and also includes the Sustainable Slip Resistance Test which will evaluate the slip resistance of your flooring sample using 50 years of international pendulum testing research into real-world slip and fall accidents, and it’ll include testing the DCOF both before and after simulated wear.
Reach out to us and get your flooring tested for DCOF slip resistance today!