Slip resistance is one of the most important decisions in any floor specification. Despite this, the terminology surrounding it often causes confusion.
Two of the most common ratings you will encounter when determining the slip resistance of tiles include the PTV rating and the R rating.
Understanding the distinction between them and knowing which to apply when is fundamental to safe and compliant floor specification.
At Parkside, we are always happy to offer you tailored advice about all aspects of your tile specification, including compliance with the various slip resistance ratings that exist.
For now, here is an overview of the key differences between PTV and R ratings.
We’ve also shared our thoughts on how we think the terminology surrounding tile slip resistance should evolve to improve clarity and ultimately safety for tiling projects in the UK.
What Is The PTV System?
The Pendulum Test Value, commonly abbreviated to PTV, is the primary slip resistance measurement used in the UK for pedestrian surfaces.
It is derived from the pendulum test, a dynamic assessment that simulates the action of a heel strike on a floor surface under wet or dry conditions. During the test, a rubber slider is swung in an arc across the tile surface and the resistance generated by that contact is measured and expressed as a numerical value.
The test is conducted in accordance with BS 7976 and is the method recommended by the Health and Safety Executive for assessing slip risk in the UK.
The PTV scale classifies surfaces as follows:
- PTV 0 to 24 - High slip risk
- PTV 25 to 35 - Moderate slip risk
- PTV 36 and above - Low slip risk
A PTV of 36 or above is the accepted minimum for most commercial pedestrian surfaces. In wet-prone areas, higher values are recommended.
The pendulum test can be carried out both in laboratory conditions and in situ, making it particularly valuable for assessing existing floors where slip incidents have occurred. Or, where compliance needs to be verified on an installed surface.
The PTV system is also used in conjunction with the Surface Roughness Value (Rz), a microscopic measurement of surface texture. Together, PTV and Rz form the basis of the UK Slip Resistance Group guidelines and are the preferred framework for most UK specifications and legal contexts.
Learn more: What is PTV? Understanding Slip Ratings And How They Work
What Is The R Rating System?
The R rating system originates from Germany and is defined by DIN 51130, a standard developed primarily for occupational safety in industrial and commercial kitchens.
The test involves human subjects walking across a contaminated inclined surface wearing standardised footwear, with the angle of inclination at which slipping occurs determining the rating. The contamination agent used is typically a mineral oil, reflecting the conditions found in food preparation environments.
The R scale runs from R9 to R13, with higher numbers indicating greater slip resistance on steeper inclines:
- R9 - Suitable for low-risk areas with occasional contamination
- R10 - Suitable for commercial kitchens, food retail and similar environments
- R11 - Suitable for areas with heavier contamination such as butcheries and fishmongers
- R12 - Suitable for areas with significant oil or grease contamination
- R13 - For the most extreme conditions, including industrial food processing
A related DIN standard, DIN 51097, uses a similar method but with barefoot subjects and water as the contamination agent. It produces a V, A, B or C classification used primarily for wet barefoot environments such as swimming pools, shower areas and spas.
How PTV & R Ratings Differ
The fundamental difference between PTV and R ratings lies in what each system is designed to measure and for whom.
The PTV pendulum test simulates a pedestrian in normal footwear encountering a wet surface. It is a broadly applicable assessment relevant across the full spectrum of commercial and public environments.
In contrast, the R rating is a workplace-specific assessment designed for environments where oil, grease or other industrial contaminants are a predictable and consistent hazard.
The two systems are not interchangeable and cannot be directly correlated.
Therefore, a tile rated R10 does not automatically achieve a PTV of 36 or above. Likewise, a tile with a strong PTV may perform poorly under the contaminated oil conditions that the R rating is designed to test.
Why The Terminology Surrounding The Slip Resistance Of Tiles Needs To Adapt
It soon becomes apparent that the divergence between PTV and R ratings creates practical problems.
For instance, a tile manufacturer may publish an R rating on its datasheet without a PTV or vice versa. Or, a specifier working across a mixed-use commercial development may need to navigate between systems depending on the zone being specified.
In other cases, a facilities manager assessing whether an existing floor is compliant may find that the documentation from the original installation uses a different system from the one required by their health and safety assessment.
The following key reasons explain why an update to the terminology is needed.
The Built Environment Has Changed
The R rating system was developed for a relatively narrow industrial context. Contemporary commercial environments, particularly in hospitality, retail and mixed-use developments, blur the traditional boundary between food service, public circulation and amenity space. A kitchen that opens directly into a dining area, a food hall with shared pedestrian routes between wet and dry zones or a hotel that integrates spa facilities with public corridors all present conditions that neither system was originally designed to address in isolation.
Tile Technology Has Moved Ahead Of The Standards
Modern tile manufacturing produces surfaces with anti-slip properties achieved through micro-texturing, structured surfaces and surface treatments that can perform differently across wet, dry and contaminated conditions. A single rating from a single test method may not adequately characterise a tile's performance across the range of conditions it will encounter in a real commercial environment.
Legal And Regulatory Language Has Not Kept Pace
In the UK, slip-related personal injury claims are assessed with reference to HSE guidance and, frequently, to PTV thresholds. However, many tile manufacturers and their UK distributors continue to market products primarily using R ratings because of established European trade conventions. This creates a disconnect in which a specifier may be purchasing on the basis of one system while their legal obligation is framed in another. If a slip incident results in a claim, the documentation trail needs to be coherent and at present it frequently is not.
Brexit And Standards Divergence Add Further Complexity
Following the UK's departure from the European Union, the relationship between UK and European standards is evolving. DIN 51130 is a German standard that became widely adopted across Europe partly through mutual recognition frameworks that no longer apply in the same way to UK practice. British Standards Institution engagement with slip resistance testing methodology is ongoing, but the current position is one of parallel systems operating without a unified framework.
International Harmonisation Is Incomplete
The ISO has been working towards a unified approach to slip resistance testing, but no single globally accepted standard has yet emerged. The UK sits in a position where it must maintain alignment with European commercial practice for import and specification purposes while also developing its own regulatory framework post-Brexit. Until a clear direction is established, practitioners are working across multiple systems simultaneously.
The Future of Slip Resistance Ratings in the UK
Perhaps the most practically significant change likely to emerge is a push for clearer, more accessible terminology.
The current situation, in which a tile can carry a PTV of 42, an R11 rating and a Rz surface roughness value with no clear guidance on which is most relevant to a given application, serves neither specifiers nor end users well.
Bodies including the UK Slip Resistance Group and the British Ceramic Tile Council, have been engaged in efforts to simplify guidance. As a result, there is a reasonable expectation that future iterations of relevant British Standards will provide more explicit decision trees for system selection.
At Parkside, we will of course, keep you up to date with any changes to tile specifications, including those relating to slip resistance. Alongside reading our blog, we also recommend following us on LinkedIn to receive any industry updates we think will be of interest to anyone involved in the planning, design or installation of commercial tiles.
Practical Guidance for UK Specifiers Now
While the standards evolve, the following principles provide a reliable framework for current commercial specifications:
Use PTV as the primary measure for all general pedestrian areas, entrance zones, corridors, washrooms and public-facing commercial spaces. Verify that the PTV is tested wet in accordance with BS 7976 and aim for a minimum of 36 in all circumstances, with 45 or above in the highest-risk wet zones.
Use R ratings for commercial kitchens, food retail preparation areas, food production facilities and any environment where oil or grease contamination is a predictable and consistent hazard.
Apply R10 as the minimum in most commercial kitchen contexts, moving to R11 or above where heavier contamination is anticipated.
Where both systems are relevant to a single project, manufacturers are required to provide data for both. Do not assume that a strong performance in one system implies strong performance in the other.
Document the basis for slip resistance specification decisions in writing, referencing the relevant standard and the test conditions under which the rating was achieved. In the event of a slip incident or a legal claim, a clear and coherent specification trail is a significant asset.
Need Help With Choosing Slip Resistant Tiles For A Commercial Project? Ask Our Experts
As leading UK suppliers of tiles for commercial projects, tile slip resistance is something we consider to be of the utmost importance here at Parkside.
For this reason, we often provide our clients with tailored advice about the slip ratings that apply to their project. If you work with us, we’d be happy to do the same.
To ask us any questions about your tile specification, please get in touch.
Or, to speak with our tile technicians directly, call us on 0116 276 2532.
