Floor Slip Testing: Pendulum Tests and PTV Explained

Floor slip testing measures how likely a floor is to cause a slip and in the UK the most widely recognised method is the pendulum test, which produces a Pendulum Test Value (PTV). A PTV of 36 or above is widely used to indicate low slip risk and it is the measurement the Health and Safety Executive references and the courts recognise as evidence when a slip claim is contested. This guide explains how the test works, what the numbers mean and when a commercial floor should be tested.

Key takeaways

• The pendulum test is the main UK benchmark. It is the method the HSE references and provides key evidence in slip liability claims.
• PTV 36+ means low slip risk. 25-35 is moderate risk and 24 or below is high risk – and floors are tested wet, because wet is when people slip.
• R ratings and PTV are different scales. A German ramp-test R rating on a datasheet is not proof of installed performance; PTV measures the floor as actually installed.
• Floors change over time. Wear, polishing from traffic and cleaning residues all reduce grip, so slip resistance is a maintenance property, not a one-off purchase.
• Testing is low-cost evidence. A documented PTV history, alongside cleaning and maintenance records, is a strong part of an operator’s defence if a slip claim arrives.

What is the pendulum test?

The pendulum test (BS 7976 series, now published within the BS EN 16165 framework) uses a swinging arm fitted with a standardised rubber slider that sweeps across the floor surface. The friction between slider and floor slows the arm and the scale reading gives the Pendulum Test Value. The rubber slider is designed to represent a shoe heel striking the ground, giving a repeatable measurement related to how a slip happens – which is why the method is trusted: it can be used on the installed floor rather than a laboratory sample and works on wet and contaminated surfaces.

Tests are carried out in multiple directions and locations and critically in both dry and wet conditions. Most clean, dry floors perform adequately, so the wet reading is usually the one that matters, because water, cleaning solution or process spillage is present in the overwhelming majority of real slips – though dry contaminants such as dust, powders and oils can create slip risks without any water.

What do PTV ratings mean?

• PTV 36 and above – low slip risk. The target for any pedestrian area, wet or dry.
• PTV 25 to 35 – moderate slip risk. Acceptable in some dry-only contexts, a warning sign anywhere water arrives.
• PTV 24 and below – high slip risk. Historical research associates this range with roughly a one in twenty chance of slipping under controlled conditions – a risk that turns into an incident book entry quickly on a busy floor.

These thresholds come from the UK Slip Resistance Group guidelines and underpin how the HSE assesses workplace flooring. There is no blanket legal minimum PTV, but the Workplace (Health, Safety and Welfare) Regulations require floors not to expose people to risk – and PTV is a primary way that risk is measured in practice, within a wider risk assessment.

How do PTV and R ratings relate?

R ratings (R9 to R13) come from a different method: the German ramp test, in which an operator in standard boots walks on an oiled sample tilted until they slip. It is a useful laboratory classification for comparing products – our guide to anti-slip resin flooring R ratings explains the scale – but it is not carried out on the installed floor and an R rating on a datasheet does not confirm how the floor performs after installation, wear and a year of your cleaning regime. It is useful information, not a substitute for site testing.

The practical rule: specify with R ratings, verify with the pendulum. A floor bought as R11 should still be pendulum tested once installed where slip risk genuinely matters, since the R rating is a product classification rather than installed performance.

When should a floor be slip tested?

At handover of a new floor. A baseline PTV proves the floor was delivered as specified and gives a reference for every later test.

On a schedule in higher risk environments. Wet process areas, commercial kitchens, entrance halls and floors in audited hygiene regimes such as HACCP-managed food production benefit from periodic testing where the risk assessment calls for it, because grip declines gradually and invisibly.

After a change. New cleaning chemicals, a switch of process, visible polishing in traffic lanes – anything that changes the surface or its contamination changes its PTV.

After an incident or claim. Post-incident testing establishes facts fast. Operators with a documented testing history are in a far stronger position than those testing for the first time after the event.

How is slip resistance built into a resin floor?

Resin systems make this straightforward: slip resistance is a deliberate specification choice rather than an accident of the finish. Aggregate broadcast into the wearing course – fine for a cleanable light texture, coarse for wet process grip – is the main lever, alongside aggregate type, density, the finish coat and how the surface wears, so a resin floor can be tuned across a wide range from smooth showroom finish to R12 wet-area workhorse within the limits of the chosen system. The trade-off is real and worth stating: the more aggressive the texture, the harder the floor is to clean, which is itself a hygiene consideration. Getting that balance right for each area is a specification decision – our anti-slip resin flooring page covers the options and it is the kind of judgement made properly at survey on industrial and commercial projects.

Frequently asked questions

What PTV should a floor have?

36 or above for low slip risk in pedestrian areas, measured wet where the floor can get wet. Between 25 and 35 is moderate risk and 24 or below is high risk under UK Slip Resistance Group guidance.

Is slip testing a legal requirement?

No specific PTV is written into law, but workplace regulations require floors that do not put people at risk and the HSE and courts treat pendulum results as key evidence of that. Documented testing – backed by cleaning and maintenance records – is the practical way to show you have managed the risk.

How much does a pendulum test cost?

It is a modest survey cost that depends on the number of locations and visits – small against the typical cost of defending a single slip claim. Quotations follow from the site specifics.

What is the difference between PTV and R ratings?

PTV comes from the pendulum test on the actual floor, wet or dry; R ratings come from a laboratory ramp test on a product sample. R ratings help compare products before purchase, PTV verifies the installed floor.

Does floor slip resistance change over time?

Yes. Traffic polishes texture flat, wear thins the profile and cleaning residues fill it. A floor that tested at PTV 40 on day one can drift below 36 in service, which is why higher risk floors are re-tested periodically.

Can an existing slippery floor be fixed?

Usually, yes – options run from deep cleaning, which restores texture that is dirty rather than worn smooth, through compatible anti-slip treatments and seal coats with aggregate, up to overcoating with a textured resin system. The right fix depends on why the floor is slippery, which testing identifies.

Get your floor’s slip risk assessed

If you are specifying a new floor or unsure where an existing one stands, the starting point is measurement rather than guesswork. Tell us about your site and we will arrange a free site survey with a vetted specialist contractor from our network – slip requirements are built into the specification and the contractor provides a written quotation, typically within 48 hours with no obligation. Contact us to get started.