Safety flooring slip ratings explained

Slip resistance is the whole point of a safety floor and it is measured, not guessed. In the UK the headline figure is the Pendulum Test Value, or PTV, from the pendulum test (historically BS 7976, now within BS EN 16165), backed up by the R rating from the German DIN 51130 ramp test that appears on manufacturer data sheets. The Health and Safety Executive treats a PTV of 36 or above as low slip risk in wet conditions with higher figures specified for ramps, pool surrounds and other high-risk areas. This guide explains what each number means, how the tests work and how to match a rating to the area you are flooring, so a specification is defensible rather than a guess.

Key takeaways

• PTV is the UK measure. The pendulum test gives a Pendulum Test Value and the HSE treats 36 or above as low slip risk in wet conditions.
• R ratings come from a different test. R9 to R13 is the German DIN ramp test used on data sheets; it is a useful guide but the PTV is what UK enforcement relies on.
• Higher risk means a higher figure. Ramps, pool surrounds and barefoot wet areas are specified above the 36 baseline, often 45 or more.
• Grip runs through the floor. Safety vinyl holds its rating because the aggregate is through the wear layer, not a surface texture that wears off.
• Specify by area. The right rating depends on how wet the floor gets, whether it is walked in shoes or barefoot and how steep it is.

What is a slip rating?

A slip rating is a measured value that tells you how much grip a floor gives, usually in the wet, so a specifier can choose a floor that is safe for the way an area is used. It replaces the guesswork of how a floor feels underfoot with a number from a repeatable test. Two systems are in common use in the UK. The Pendulum Test Value, or PTV, comes from the pendulum test (historically BS 7976, now within BS EN 16165) and is the figure UK enforcement and risk assessment rely on. The R rating, from R9 to R13, comes from the German DIN 51130 ramp test and is quoted on most manufacturer data sheets. The two are not directly interchangeable, which is why it helps to understand both rather than reading one across to the other.

What is the pendulum test and PTV?

The pendulum test is the UK standard method for measuring slip resistance and it gives the Pendulum Test Value. A weighted arm with a rubber slider swings across the floor and the machine measures the friction between a standard rubber slider and the floor surface under controlled conditions. The result is the PTV, a single number. The higher it is the more grip the floor gives. The pendulum method was historically set out in BS 7976 and is now covered within BS EN 16165 (Annex C) and it can be run wet or dry and with different sliders to represent a shod or a barefoot condition, so a floor is tested in the state it will actually be used in. Because it can be done on site as well as in a lab, the pendulum is also the test an assessor uses to check a floor that is already down, which is why it carries weight with the HSE and in litigation after a slip.

What PTV do I need? The HSE thresholds

The Health and Safety Executive uses the pendulum result to band a floor by risk. A PTV of 36 or above is treated as low slip risk in wet conditions, a PTV of 25 to 35 as moderate risk and 24 or below as high risk. In plain terms a commercial floor that gets wet should be at 36 or above and most safety flooring is specified to clear that comfortably. The 36 figure is the baseline, not the ceiling. Areas where the consequence of a slip is higher, or where the floor is wetter or steeper, are specified above it, commonly at 45 or more. That covers ramps, pool surrounds, shower and changing areas and any barefoot wet space. The point of the banding is that a floor is chosen against the risk of the area rather than a blanket number, so the survey and the specification matter as much as the product.

What are R ratings and the ramp test?

The R rating comes from the DIN 51130 ramp test, a German method where a person in standard boots walks up an oiled ramp that is gradually tilted until they slip and the angle at which they slip sets the rating. The scale runs from R9, the lowest, to R13, the highest. It is the figure you will see most on manufacturer data sheets, so it is useful for comparing products, but it is a shod test done with oil rather than water and it does not translate cleanly into a PTV. As a rough guide R9 suits dry internal areas, R10 general wet areas such as washrooms and kitchens, R11 wetter or greasier commercial areas and R12 to R13 the heaviest industrial and food-production floors. These are typical applications rather than prescribed classifications and manufacturers vary. There is also a separate barefoot ramp test, graded A, B and C, used for wet barefoot areas like pool surrounds. Treat the R rating as a helpful indicator and the PTV as the figure that answers to UK enforcement.

PTV or R rating: which should I specify to?

Specify to the PTV and use the R rating to shortlist products. UK risk assessment, HSE guidance and slip litigation all turn on the pendulum result, so a specification written around a target PTV for the area is the one that stands up if it is ever questioned. The R rating is genuinely useful earlier in the process, because it lets you compare ranges quickly on a data sheet and rule out anything obviously too low, but it should not be the final word. A floor can carry a healthy R rating and still be wrong for a barefoot wet area, because that is a different test. The practical approach is to set the PTV the area needs, use the R rating and the barefoot rating to narrow the product options and then confirm the choice against the manufacturer’s pendulum data. Our child pages set out the typical figure for each area, from commercial kitchens to pool surrounds.

How does safety flooring achieve its slip rating?

Through hard aggregate carried all the way through the wear layer, not a texture pressed into the surface. Safety vinyl has particles of aluminium oxide or carborundum, the same abrasives used on sandpaper and grinding wheels, distributed through the thickness of the wearing surface. As the floor is walked on and cleaned, fresh aggregate is always presented at the surface, so the grip is maintained rather than worn away. That is the essential difference between a safety floor and a standard vinyl or LVT floor that relies on a surface finish: a textured coating grips until it wears smooth, whereas a through-aggregate safety floor holds its rating for the life of the floor. It is also why a safety floor should never be polished or sealed with a smooth coating, because a film on top buries the aggregate and defeats the very thing it was chosen for. The trade-off is that a heavily aggregated floor is harder to clean, which is why cleaning method matters and is covered in our maintenance guide.

Does slip resistance wear off over time?

Not in the way a surface texture does, but it can be masked by poor cleaning. Because the aggregate runs through the wear layer, a correctly specified safety floor keeps its underlying slip resistance for years of normal use. What changes grip in practice is contamination: soap film in a shower, grease in a kitchen, body oils and sunscreen around a pool, or a build-up of cleaning residue anywhere. These sit in and over the aggregate and reduce the effective grip even though the floor itself has not worn out. The fix is method, not replacement. Regular scrubbing that works into the aggregate with a neutral detergent and the right pad or brush, lifts the film and restores the grip the floor was specified to give. A floor that is only flat-mopped will slowly feel less grippy as residue builds, which is the most common reason a safety floor underperforms its rating. Our cleaning and maintenance guide sets out the regime that keeps a floor at its rated value.

How is slip resistance tested on a floor that is already down?

With the same pendulum test, run on site. One of the strengths of the pendulum is that the machine is portable, so an assessor can test an existing floor in place, wet or dry, in the exact spot where a slip happened or where a risk is suspected. That is why the pendulum result is the figure that carries weight after an incident: it measures the floor as it actually is on the day, complete with whatever wear, contamination or polish it has picked up, rather than the value it left the factory with. For a duty-holder this cuts both ways. A floor specified and maintained to the right PTV gives evidence that the area was managed properly, while a floor that has dropped below the threshold through poor cleaning or the wrong specification is exactly what an assessment or a claim will expose. Getting the specification right at the survey stage and keeping the floor clean are the two things that keep the on-site figure where it should be.

Slip ratings by area at a glance

Different areas need different figures, which is the whole reason a floor is specified rather than picked off a shelf.

• Dry internal areas. Offices and dry circulation need only a standard floor, around R9, where slip risk is low unless water is tracked in.
• Washrooms and general wet areas. Commercial WCs and washrooms are specified at or above the PTV 36 wet threshold, typically around R10.
• Commercial kitchens. Grease and water push catering floors higher, commonly to products around R11 or R12, provided they also meet the pendulum performance the area needs.
• Ramps and level changes. A wet slope is a higher risk than a wet level floor, so ramps are specified above the baseline, often PTV 45 or more.
• Barefoot wet areas. Showers, changing villages and pool surrounds are specified with a barefoot rating and at the higher, wetter end of the scale.

These are starting points, not a substitute for a survey. The right figure for a given room depends on how wet it gets, what is spilled on it, whether it is walked in shoes or barefoot and how it is cleaned, which is why the specification is confirmed on site.

Get the specification right with a free survey

Choosing the right slip rating is a judgement about risk, use and cleaning and it is best made once someone has seen the area. Surface Specialists helps businesses get the right safety floor. We arrange a free site survey and match your project to a vetted safety flooring contractor in our network, who assesses the area, confirms the slip rating and specification it needs and provides a written quotation. For a specific area see our pages on wet rooms and changing rooms, commercial kitchens, washrooms, pool surrounds and stairs, or start at our commercial safety flooring hub. Where a resin finish suits an area better than vinyl, our anti-slip resin flooring page covers that option.

Frequently asked questions

What does PTV mean?

PTV stands for Pendulum Test Value, the result of the UK pendulum slip test (historically BS 7976, now within BS EN 16165). It measures how much grip a floor gives, usually in the wet. The higher the number the more slip-resistant the floor. The HSE treats a PTV of 36 or above as low slip risk in wet conditions.

What PTV is safe for a wet floor?

The HSE treats a PTV of 36 or above as low slip risk in wet conditions, so a commercial wet floor should be at 36 or higher. Ramps, pool surrounds and barefoot wet areas are specified above that, often at 45 or more, because the risk is greater.

What is the difference between PTV and R rating?

They come from different tests. The PTV is from the UK pendulum test and is the figure UK enforcement relies on. The R rating, R9 to R13, is from the German DIN ramp test and appears on data sheets. Use the R rating to compare products and specify to the PTV the area needs.

What does R10 or R11 mean?

They are grades from the DIN ramp test. R9 suits dry areas, R10 general wet areas like washrooms, R11 wetter or greasier commercial areas and R12 to R13 heavy industrial and food-production floors. A higher R number means more grip in the shod ramp test.

Does safety flooring lose its grip over time?

Not through normal wear, because the aggregate runs through the wear layer rather than sitting on top. What reduces grip in practice is contamination such as grease, soap film or cleaning residue, which regular scrubbing into the aggregate removes. A floor that is only flat-mopped slowly feels less grippy as residue builds.

Can slip resistance be tested on an existing floor?

Yes. The pendulum test machine is portable, so an assessor can test a floor in place, wet or dry, in the exact spot of concern. That on-site figure is what carries weight in a risk assessment or after a slip, because it measures the floor as it actually is on the day.