Floor slipperiness is measured using pendulum testing, the method recognised by the HSE for assessing slip resistance. A weighted pendulum swings across the floor surface and records the resistance it meets, producing an objective slip resistance value for that floor, both wet and dry. This gives a precise number rather than a visual impression, which is the only reliable way to know how safe a floor actually is.
The short why
You cannot judge slip resistance by looking at a floor or walking across it. Grip is a physical property of the surface, and it changes depending on contamination, footwear and cleaning products. Measuring it with a standardised method removes the guesswork and gives a result that can be compared, tracked and acted on.
How pendulum testing actually works
The pendulum swings across the surface. A rubber slider on the end of a calibrated pendulum arm is released across the floor, replicating the action of a heel striking the ground. The resistance it meets produces a Pendulum Test Value, or PTV, which is the standard measure of slip resistance used across the industry.
Testing happens wet and dry. A floor’s grip changes significantly once it becomes wet, so a proper assessment tests both conditions. A floor that performs well dry can drop to a genuinely dangerous PTV once water is introduced, which is exactly the kind of hidden risk that a visual check would never reveal.
Results are compared against a safe threshold. Once a PTV is recorded, it can be checked against recognised safety thresholds for that type of area and footfall. This turns a subjective sense of “this floor seems fine” into an objective answer, backed by a number.
Why testing once is not the same as being safe
This is where many venues get the wrong idea. A single test result tells you the condition of a floor on the day it was tested, nothing more. Floors change over time as cleaning products build up, surfaces wear, and footfall patterns shift, so a good result last year does not guarantee a good result today.
The belief that testing equals compliance, and compliance equals safety, misses the point. A number on its own does not prevent a single slip. What actually reduces risk is what happens after the test: improving any floor that falls short, and then maintaining that improvement over time. Measure, improve, prove is the fuller picture, and it is where the real reduction in risk comes from.
What actually happens after a floor is tested?
Once a floor has been measured, the result should lead somewhere. If the PTV falls below a safe threshold, the surface or its maintenance needs to change, whether that means a different cleaning product, a surface treatment, or both. After treatment, the floor is retested to confirm the improvement has actually worked. Slip Safety Services has recorded slip resistance improvements as significant as a 50,000x reduction in risk on floors moved from a PTV of 24 to 36 or higher when wet, through this kind of tested, treated and retested approach.
What to do about it
If your venue has been tested before but never retested, or if testing happened once and was treated as a box ticked, it is worth revisiting. Start by identifying your highest-footfall or highest-risk areas, such as entrances, bars, kitchens and washrooms. From there, get those specific areas properly measured, so any decision about treatment or cleaning is based on an actual number rather than how long it has been since the last check.
Your next step
If you want a quick sense of where your floors currently stand before committing to a full test, the Slip Risk Scorecard is a fast way to find out. It takes a few minutes and gives you an honest starting picture.
Related questions
- What causes slippery floors in hotels?
- Are wet floor signs enough to prevent slips?
- How often should floors be tested for slip risk?
- What PTV is considered safe for a wet floor?
Slip Risk Scorecard: “take the Slip Risk Scorecard“
