If you manage a building or specify flooring, you have probably been asked whether your floor is "slip resistant" — and how you can prove it. The pendulum slip test is the answer. It is the method the Health and Safety Executive (HSE) prefers for measuring how slippery a floor really is, and it produces a single, defensible number you can put in front of an insurer, a client, or a court.
What the pendulum test actually measures
The pendulum test measures the slip resistance of a floor — in effect, how much grip there is between a shoe (or bare foot) and the floor at the moment a person's heel strikes it while walking.
The test uses a swinging arm fitted with a rubber slider that mimics the heel of a shoe. The arm is released, the slider sweeps across the floor, and friction slows it down. The more grip, the more the swing is slowed. That result is read off as a Pendulum Test Value (PTV).
Crucially, the test can be run on a wet floor as well as a dry one. That matters because the overwhelming majority of slips happen when a floor is contaminated — usually with water. A floor that grips well when dry can become dangerous the moment it gets wet, and only a wet test reveals that.
How the test is carried out
A professional pendulum test follows the method set out in BS EN 16165:2021 (Annex C) and the UK Slip Resistance Group (UKSRG) Guidelines, Issue 6 (Jan 2024). In practice that means:
- The floor is tested in three directions to capture how it behaves whichever way someone walks across it.
- It is tested in both dry and wet conditions, because the wet result is usually the one that matters for risk.
- The lowest reading is taken as the most honest indicator of risk, not a flattering average.
Two different rubber sliders are used depending on the environment:
- Slider 96 (formerly "4S") — used for areas where people wear shoes.
- Slider 55 (formerly "TRRL") — used for barefoot areas such as pool surrounds, changing rooms and bathrooms.
Testing can be done on-site, or on a sample sent to a laboratory.
What your result means
The PTV is banded into three levels of slip potential — the classification published by HSE and UKSRG:
| Slip potential | Pendulum Test Value (PTV) |
|---|---|
| High | 0 – 24 |
| Moderate | 25 – 35 |
| Low | 36 and above |
A PTV of 36 or above corresponds to what the research describes as an acceptably low risk of slipping — roughly a one-in-a-million chance for a reasonably active adult walking in a straight line on the level. It is worth stressing that the PTV is not a simple pass/fail. It forms part of a wider risk assessment that also considers footwear, contamination, cleaning regimes and how the space is actually used.
Why it's worth doing
A pendulum test gives you three things a visual inspection never can: an objective number, a written report, and a paper trail. If someone slips and a claim follows, being able to show that your floor was independently tested — and, if needed, treated to bring it up to standard — is powerful evidence of due diligence.
Frequently asked questions
How long does a pendulum test take?
A typical on-site test takes a couple of hours depending on the number of areas. You will receive a digital report with the PTV results.
Is the pendulum test recognised by the HSE?
Yes. HSE describes the pendulum as its preferred test method because it is portable and works in the wet conditions where slips occur.
My floor failed. What now?
A low PTV doesn't mean you must rip the floor out. An anti-slip treatment can often raise the slip resistance of your existing floor, and a re-test then documents the improvement.