Pendulum DCOF Slip Resistance Test Method

Pedestrian Floor Slip Resistance Testing

Contact John at 949-933-6971 for field or laboratory British pendulum (or ASTM E303-22) DCOF floor slip resistance or road skid resistance tests. Turnaround time for lab floor friction tests is normally two-three working days, and the charge for most samples is $265.00 per sample (a sample is one to three representative pieces of the same material). Field floor slip resistance testing charges are for time and expenses from southern California. We can also annually calibrate your British pendulum in our laboratory (see bottom of page for details). As a validation of our expertise in pendulum calibration (and operation) an international study has found us to be one of the world’s top three pendulum labs for accuracy.

The British pendulum is the most accepted pedestrian slip resistance test method worldwide. The test is well-proven and long backed by an ASTM (American Society for Testing and Materials) standard ASTM E303-22 that was validated in 1971 by 3500 test results in the United Kingdom on walking surfaces obtained over more than 25 years. The pendulum received the highest rating for correlation with human traction in a peer-reviewed published scientific study of 11 types of tribometers (friction meters) by the University of Southern California Medical Center.

Slip Resistance Testing for Tile/Floors

The world’s best and most sophisticated safety standards and the test method to go with them are in Australian Standards HB198. There are situation-specific safety standards for Pendulum Test Value (PTV) for more than 27 specific situations. Recommended minimum wet PTV’s range from 12 (for dry areas) to 55 (swimming pool ramps and stairs leading to water.) We recommend using these standards to supplement the rudimentary minimum of 0.42 wet dynamic coefficient of friction in ANSI A137.1 and ANSI A326.3, incorporated by reference in the International Building Code. Those minimums do not protect the building owner from liability, since it requires that the user consider numerous other factors. We recommend using HB198 to allow for those factors.

Floor Slip Resistance Testing and Road Skid Resistance Testing

The method for pedestrian slip resistance testing and road skid resistance testing in the United States is described in the newly-revised ASTM E303-22, the “Standard Test Method for Measuring Surface Frictional Properties Using the British Pendulum Tester”. Data on precision and bias relevant to human traction are available for that method, as a precision statement is included in E303. Some of the bias data are in an ASTM Publication: STP 1424, pp. 112-136. Greater London Council Bulletins 43 and 145 contain validating information dating from publication in 1971 and 1985. The safety criterion specified in those bulletins has become a standard in the United Kingdom, Australia, Dubai, Malta, New Zealand, Singapore, Spain, and other countries that follow British law, and has been in use continuously, with the same numerical safety criteria (shown here in a document published by the United Kingdom’s Health and Safety Executive), since 1971.

As ASTM E303-93 was updated in 2022, it now more closely mirrors other pendulum test methods from around the world, such as AS 4663 and EN 16165. We can now use the ASTM E303 test method to measure both the slip resistance of floors and the skid resistance of roads using the same test method with the pendulum slip resistance tester. The harder Four S rubber (Standard Shoe Sole Simulating) is most commonly used when testing floors, and the softer TRL rubber (Transport & Road Laboratories) is usually used for road skid testing, although the softer rubber is also used for testing floors that will be used by barefoot pedestrians. The ASTM E303 floor friction test method now has greater precision and is much more reliable and useful with the new 2022 improvements to the test method, and so we can reliably now use the floor slip resistance testing safety criteria used in other countries with America’s version of the pendulum DCOF test.

Here’s a video of the pendulum DCOF tester in action:

The pendulum test method and its safety standard have these advantages:

  • Developed in the USA by the U.S. National Bureau of Standards
  • Specified by ASTM E303 for decades, with precision data included in the ASTM standard
  • Validation [bias] study of 3500 test results over 25 years, accepted by many government agencies internationally, and other published studies
  • In continuous use for assessing pedestrian slip resistance since 1971
  • International acceptance in courts of law
  • An international study established Sotter Engineering/Safety Direct America as one of the top three most accurate pendulum test laboratories worldwide

The British pendulum dynamic coefficient of friction (DCOF) test method is the national standard for pedestrian slip resistance in at least 50 nations on five continents. This includes:

Armenia, Austria, Australia, Azerbaijan, Belarus, Belgium, Bosnia-Herzegovina, Bulgaria, China, Cyprus, Czech Republic, Denmark, Dubai, Egypt, Estonia, Finland, France, Georgian Republic, Germany, Greece, Hungary, Iceland, India, Ireland, Israel, Italy, Latvia, Lithuania, Luxembourg, Macedonia, Malta, Moldova, Netherlands, New Zealand, Norway, Poland, Portugal, Romania, Russia, Serbia, Singapore, Slovakia, Slovenia, Spain, Sweden, Switzerland, Tunisia, Turkey, Ukraine, the United Kingdom, and the United States of America.

Many other nations, like South Africa, don’t try to re-invent the wheel. They use the European floor friction test methods, which includes the pendulum tester for reliable results in both the lab and field.

The pendulum method has been endorsed by Ceramic Tile Institute of America since 2001. It is also used for indoor and (by ASTM Specification F 2157 – 09) outdoor sports surfaces. The National Sanitation Foundation (NSF), together with American National Standards Institute (ANSI) and National Standard of Canada (CAN) established a slip resistance standard for recreational water facilities, including splash pads and water parks. Formalized in NSF/ANSI/CAN 50 – 2019, the standard requires a wet Slip Resistance Value, SRV, of 40 or greater, measured using the pendulum slip resistance test method. Other ASTM test methods for wet slip resistance are obsolete and include no safety standards. The pendulum DCOF tester is also used in AASHTO T 278 in the USA. Click here for more information on the C1028-07 test method, which is NOT endorsed by the ADA and is not appropriate for assessing pedestrian slip risk.

Percy A. Sigler at the U.S. National Bureau of Standards developed the pendulum method specifically for assessment of pedestrian traction potential, publishing his results in 1948. Minor modifications to ASTM E 303-93 (2013) and safety standards for pedestrian traction are specified by the United Kingdom Slip Resistance Group in their 2011 publication “The Assessment of Floor Slip Resistance: The UK Slip Resistance Group Guidelines (Issue 4)”. This group ( has members in the UK, USA, and Australia who contributed to the fine-tuning of the guidelines based on experience with the method. Two members of the committee represent the British Governments Health and Safety Executive.

British Pendulum Calibration

British pendulum calibration used to require sending your pendulum over to Europe for a few weeks or more. The pendulum needs to be calibrated annually, and we can calibrate your British pendulum here at Sotter Engineering/Safety Direct America in California in a matter of a few business days in most cases. We’ve been calibrating the British pendulum for well over 10 years here in the USA for many clients both domestic and abroad. Please call (949)933-6971 or email for details concerning British pendulum calibration here in the United States. The price for pendulum calibration is $850.00, plus the cost of shipping to and from our lab (which preferably can be done on your FedEx or UPS account). This price assumes we won’t need to replace any broken or missing parts on the pendulum. We have been found to be one of the world’s most accurate pendulum test labs in an international study after nearly twenty years of calibrating our own in-house pendulums.

Please click on British Pendulum Calibration Services for more information and to pay online for your pendulum tester to be calibrated in the USA today.

More Information on pendulum slip resistance testing:

Buy Your Own Pendulum Slip Resistance Test Device (Tribometer)

KSS British Pendulum and supplied accessories

The pendulum slip resistance tester is presently used for measuring pedestrian slip resistance in at least 50 nations on five continents. This pendulum DCOF test device (sometimes called the British Pendulum) is endorsed by the Ceramic Tile Institute of America and has an American test method for its use – ASTM E303-22. It’s also used to assess slip risk all over Europe and the United Kingdom with BS EN 16165:2021, in Australia and New Zealand with AS 4586 and AS 4663, and plenty of other test methods in various nations around the globe (China, Singapore, India, Israel, etc., etc., etc.). We recommend the pendulum for the most reliable results in assessing real-world slip risk based on 50 years of international research. Perfect for lab and field testing. It’s also used to measure the skid resistance of roads using ASTM E303-22. Includes hard flight case, four rubber sliders, and all other tools in the photo above. The verification sample holder and float glass sample can be purchased at checkout along with your pendulum, or you can order a pendulum without those items to save a bit of money. We can usually have one on your doorstep within 5-7 business days of payment, freshly calibrated. You will be responsible for paying any customs duties before DHL delivers your pendulum since it’s coming directly from the manufacturer in the United Kingdom (so that the calibration and sliders are as fresh as possible.)
$6,240.00 (delivered to you in the lower 48 states) or $6,640.00 with verification holder and float glass

Buy Floor Safety Now

We also sell new rubber sliders for the pendulum tester. We have them with the aluminum backing or just the rubber itself (which you can replace yourself on your old aluminum backing.) We have FourS rubber (IRHD of 96) for shod pedestrian testing, TRL (IRHD of 55) for barefoot pedestrian and roadway testing, and CEN rubber (IRHD of 57) for the European pendulum test method EN 16165:2021.

pendulum tester rubber slider

$133.00 for just the rubber. or $223.00 with the aluminum backing plate

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