Verifying the Pendulum Tester

The Pendulum Tester should be verified at the start of each day of testing, as well as after re-assembly/transportation. The verification procedure is a very important part of the slip testing process. It demonstrates to you, and all those making use of your results, that the instrument has been correctly set-up and is functioning properly.

Verification is achieved by performing pendulum tests on a set of standard surfaces with known PTVs. These are given in the table below:

TRL(55) Rubber Slider
4S(96) Rubber Slider
59-64 PTV
5-10 PTV
5-10 PTV
13-19 PTV
32-36 PTV


If the values given in the table are not obtained during the verification procedure, you must not proceed with testing. The pendulum setup procedure (including slider conditioning) should be re-performed, and rubber sliders checked for defects. If you continue to experience difficulties verifying your instrument, please contact us for further assistance.

References & Further Reading

We recommend that all Pendulum users purchase a copy of the UK Slip Resistance Group Guidelines (see reference below).

UK Slip Resistance Group, The UK Slip Resistance Guidelines, Issue 4.0,UKSRG (2016)

  • Available to purchase here

Please also refer to the specific British or International Standard to which you are testing.  Minor variations in the verification procedure are present in some standards.