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Method & accreditation
Slip resistance is invisible and changes over time. Two complementary methods measure it properly — and we’re accredited for both.
A weighted arm swings a calibrated rubber slider across the floor to reproduce a slipping heel, recording grip as a Pendulum Test Value. We test wet and dry, in three 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 floor needs enough microscopic roughness to break through contaminants and grip footwear. Roughness testing tracks that, and works best alongside the pendulum — especially in kitchens, factories and other areas that 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 towards the low-risk band.
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.
Surface Performance is entirely independent: no connection to any flooring manufacturer, treatment company or equipment maker, and no commission from anyone. UKAS-accredited (UKAS Testing Laboratory No. 7933, ISO/IEC 17025), and recognised by RoSPA, FIFA, World Rugby, the ITF and FIH for related work. Nothing influences the figure.
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.