Pendulum Test Value (PTV): How BS 7976 Measures Floor Slip Resistance

The Pendulum Test Value (PTV) is the result of a standardised slip-resistance test widely used in the UK and beyond to assess floor safety. The test simulates the action of a heel striking a surface, delivering a numerical score that indicates whether a floor poses a low, moderate or high slip risk. For building professionals specifying finishes in public buildings, workplaces or wet environments, understanding PTV thresholds and the test methodology is essential for meeting regulatory requirements and mitigating liability.

How the Pendulum Test Works

The Pendulum Slip Test—also known as the British Pendulum Test—uses a calibrated swinging arm fitted with a rubber slider. As the arm swings down, the slider contacts the floor surface; friction causes the arm to lose momentum, and the distance travelled after impact determines the PTV. Two slider types are specified: Slider 96 simulates footwear contact, while Slider 55 is used for barefoot conditions. The test can be conducted on-site or in the laboratory, and standards that reference it include BS 7976 for pedestrian surfaces, EN 1341 for external paving and EN 14231 for natural stone modular tiles.

Testing is carried out in multiple directions—with, across and diagonal to foot traffic—and on both dry and wet surfaces. This approach captures the real-world variability of floor conditions and ensures results are representative of the environment in which the floor will be used.

What PTV Scores Mean for Slip Risk

The PTV scale translates numerical results into slip-potential classifications:

In the UK, a wet PTV of 36 or higher is generally treated as the threshold for low-risk surfaces in public and commercial environments. Floors scoring below 25 under wet conditions pose a significant hazard and typically require remedial action—whether resurfacing, treatment or replacement.

The test is recognised by the Health and Safety Executive (HSE), the UK Slip Resistance Group (UKSRG) and is admissible in court as evidence of compliance with duty-of-care obligations under the Health and Safety at Work Act 1974. It is also the only slip-resistance method explicitly endorsed by HSE guidance.

Regulatory Context and Duty of Care

Floor finishes must not be slippery to the extent that they put people's safety at risk—a requirement enshrined in the Safety, Health and Welfare at Work (General Application) Regulations 2007. This duty of care applies to flooring designers, manufacturers, distributors, installers, contractors and the architects who specify flooring products. All parties must ensure that surfaces are fit for purpose and do not pose a safety risk.

Pendulum testing provides objective, repeatable data suitable for compliance audits, insurance claims and post-incident investigations. It is the only slip-resistance test method that holds up in a court of law; results from other methods are generally inadmissible as evidence.

Materials and Test Frequency

The test is applicable to a wide range of materials, including ceramic, porcelain, granite, slate, marble, natural stone, clay pavers, concrete paving blocks and flags, cement, timber, resin finishes, PVC and other flexible materials, glass, metal and plastic. On-site consultancy can identify factors that influence slip performance, such as cleaning regimes, maintenance, integrity of substrate, wearing or weathering of the flooring surface, presence of sealants and trafficking patterns.

Testing frequency depends on the environment. High-traffic areas, spaces exposed to water or contaminants and zones with a history of slip incidents should be tested more frequently. Regular testing also supports monitoring of cleaning regimes and the effectiveness of anti-slip treatments.

PTV vs R Ratings

While PTV is the preferred metric in the UK, some European standards use R ratings (e.g. R9, R10, R11) to classify slip resistance. R ratings are derived from ramp tests and are commonly cited in product specifications for tiles and flooring. However, the Pendulum Test is considered more representative of real-world pedestrian conditions and is the only method explicitly recognised by the HSE. For UK compliance and legal purposes, PTV results take precedence.

Implementation and Compliance

For building professionals, specifying floors with a documented PTV above 36 under wet conditions provides a defensible basis for demonstrating compliance. On existing floors, regular slip testing can identify deteriorating surfaces before incidents occur. The test is also valuable during product development: manufacturers can benchmark new finishes against performance thresholds before market introduction.

The combination of standardised methodology, regulatory endorsement and legal admissibility makes the Pendulum Test Value the benchmark for slip-resistance assessment in the UK. As regulatory scrutiny on workplace safety intensifies, PTV data will remain a critical component of risk management and specification practice.