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Method & accreditation

Two tests the HSE recognises

Slip resistance is invisible and changes over time. Two complementary methods measure it properly — and we’re accredited for both.

1 · Pendulum slip testing (PTV)

A weighted arm swings a calibrated rubber slider across the floor to reproduce a slipping heel, and records the grip as a Pendulum Test Value. We test wet and dry, in three different swing directions, with the correct slider for how the floor is used.

PTV result	Slip risk
0–24	High
25–35	Moderate
36 +	Low

A PTV of 36 or above is the HSE’s low-risk threshold; anything below 36 should be managed.

2 · Surface (micro) roughness testing (Rz)

A floor needs enough microscopic roughness to break through contaminants and grip footwear. Surface-roughness testing tracks that, and is best used alongside the pendulum — especially in kitchens, factories and other areas where floors get wet or greasy.

Surface roughness (Rz)	Slip risk
Below 10	High
10–20	Moderate
Above 20	Low

Roughness is measured in microns; an Rz below 20 should be managed back up towards the low-risk band.

The standards

• BS 7976-2 — operation of the pendulum tester.
• BS EN 16165 — the current standard for measuring surface slip resistance (it superseded BS EN 13036-4).
• UKSRG guidelines — how the results are interpreted in practice (we’re a UKSRG member).

Every duty holder has to manage slip risk — employers, facilities managers, and in care settings the CQC, which expects it to be actively assessed and controlled. A measured PTV or Rz result is that evidence.

Laboratory product testing

Beyond on-site work, our environmentally controlled laboratory (to ISO 291) tests more than 300 flooring products a year — tiles, stone, resin, vinyl, decking and more — and can issue slip-resistance certification or support product development. Useful if you want a floor tested before you buy it.