Published 2026-02-22 · Slip-Tests UK
What is a Pendulum Test Value?
The Pendulum Test Value (PTV) is a numerical measure of floor slip resistance produced by the BS 7976-2 pendulum test. The apparatus — originally developed in the 1940s for road-surface testing — uses a weighted pendulum arm fitted with a rubber slider that strikes the floor surface and swings across it. The deceleration of the pendulum is measured and converted to a PTV from 0 to 150.
Higher values mean higher slip resistance. Lower values mean lower slip resistance. The HSE and the UK Slip Resistance Group (UKSRG) have established numerical thresholds that classify any PTV reading into three bands.
The three thresholds
| PTV | Classification | Meaning |
|---|---|---|
| 36+ | Low slip potential | Compliant and acceptable. Floor is suitable for commercial use. |
| 25–35 | Moderate slip potential | Active management required — matting, signage, cleaning regime. |
| Below 25 | High slip potential | Unacceptable. Immediate remediation required. |
Dry vs wet: the critical distinction
A single PTV figure is never enough. Every floor must be tested in both dry and wet conditions, because the two can differ dramatically. A polished porcelain tile might produce a dry PTV of 45 and a wet PTV of 12 — perfectly safe when dry, lethally slippery when wet. A textured rubber mat might produce a dry PTV of 60 and a wet PTV of 58 — almost no variation.
The single most common mistake in UK slip testing is to consider only dry PTV. For a floor in a UK commercial environment, the wet PTV is almost always the figure that matters — because real-world slip incidents overwhelmingly occur in wet or contaminated conditions.
What slider do you use?
The pendulum test uses different rubber sliders for different purposes. BS 7976-2 / BS EN 16165 slider 96 is used for shod (shoe-wearing) environments — the normal commercial specification. Slider 55 is used for barefoot environments like swimming pools and shower trays. Any competent UKAS report will state the slider used — and the classification thresholds apply equally to both sliders.
Site-specific context matters
The 36/25 thresholds are the baseline, but specific environments have their own norms. Wet pool surrounds are tested additionally using DIN 51097 (a ramp test) and classified A/B/C — class C is the highest. Ramp sports surfaces have their own R-rating range (R9-R13) under DIN 51130. Industrial environments may have client-specific thresholds (often PTV 40+) reflecting higher contamination risks.
Reading a pendulum test report
A UKAS-accredited BS 7976 / BS EN 16165 report should show, for each test area: the PTV in dry conditions (usually averaged over multiple test runs), the PTV in wet conditions, the slider type used, photographs of the test location, and a classification against UKSRG thresholds. The report should also state the instrument calibration reference and the engineer’s qualifications.
If any of those elements are missing, the report is not meeting UKAS standards — regardless of what badge it carries.
Getting below 36
Most commercial floors can be brought above PTV 36 by one or more of: changing the floor surface (replacement or overlay), applying a chemical or mechanical anti-slip treatment, changing the cleaning regime, improving matting and drainage, or removing contamination sources. The right answer depends on which PTV — dry, wet, or both — is failing, and why.
A good UKAS testing report identifies the problem; good remediation advice (independent from the testing laboratory, to preserve impartiality) identifies the solution.