Printed from the ArchiMentor Knowledge pages on - www.archimentor.net

Slip resistance

• Introduction
• Pendulum test method
• Alternative test methods
• Slip resistance and surface roughness
• Further reading

Introduction

• The issue of the slip resistance of flooring is still highly confusing and emotive despite numerous attempts to reach agreement on common methods of assessment. This page must be regarded as no more than a starting point for serious research, if such is required.
• Specifiers should be aware that there is no relationship between the results obtained from the pendulum, ramp, and sled test methods and this may mean that direct comparison between products sourced from different EU countries (which favour different test methods) may be impossible.
• Slip resistance is referred to in Approved Document B of the Building Regulations.

Pendulum test method

• BS 7976 Pendulum Testers. Covered by BS 7976, Parts 1 to 3, these are now the preferred method for testing the slipperiness of floors in the UK. The test is referred to in several British Standards, the HSE publication attached, and many other authoritative documents.
• From the Foreword to BS7976-2:2002:
  The pendulum tester was originally designed by Percy Sigler in the USA in the 1940s to test pedestrian surfaces. It was adopted and further developed in the late 1950s by the then Road Research Laboratory (RRL, now known as the Transport Research Laboratory, TRL). This design has remained basically unchanged to the present day, and other designs based on the same principle are now available. The pendulum tester specified in BS 7976-1 operates on the principle used in the original RRL apparatus.
• When assessing the results of pendulum tests it is crucial to know the type of rubber used in the "slider". Tests carried out in prior to the mid 1990s are more likely to use the "TRL" rubber whereas more recent tests should have been carried out using the "Four-S" (standard simulated shoe sole) rubber. Although the results are not directly comparable it is helpful to display them together to minimise the possibility for any misunderstanding:

SRV (slip resistance value) using TRL rubber slider	Safety category	PTV (pendulum test value) using Four-S rubber slider	Slip risk
19 and less	Dangerous	0 to 24	High
20 to 39	Marginal	25 to 35	Moderate
40 to 74	Satisfactory	36 to 64	Low
75 and over	Excellent	65 and over	Extremely low

Alternative test methods

Ramp tests

• Ramp tests have a long history in continental Europe but use of the results is now actively discouraged by UK authorities such as the HSE. You will find, however, that many manufacturers are still quoting 'R' values to DIN 51130 in their trade literature. There is no direct correlation between the results of the pendulum test and the various ramp tests and it is virtually impossible to make a true comparison between products tested to the different standards.
• DIN 51097. This is specifically for testing floor coverings in "wet-loaded barefoot areas". There are three categories, A to C, with A the "worst" and C the "best".
• DIN 51130. This is the more widely used-and-quoted of the two DIN tests. There are five categories, R9 to R13, with R9 the "worst" and R13 the "best". The DIN standard provides examples of suitable uses for each category.
• HSL (Health and Safety Laboratory) Ramp Test. This has been developed as the UK equivalent of the two DIN ramp tests and has useful applications for specific laboratory tests, as explained in the CIRIA book referred to below. It cannot be used on site and has not yet been developed to the stage where it has as wide an application as the pendulum test.

Sled tests

• The use of these is now actively discouraged by UK authorities such as the HSE, and few flooring manufacturers now quote results from these tests in their trade literature.
• BCRL Bench Friction Apparatus (Tortus). There has been significant debate about the validity of the results from this test in wet conditions and the test is now rarely used.

SlipSTD

• The SlipSTD Project [http://www.slipstd.com/], part-financed by the European Commission, is an attempt to produce a harmonised classification system for defining slip resistance requirements. But, as the article in the November 2009 edition of the RIBA Journal suggests, the classification method proposed by the SlipSTD Project is unlikely to replace the pendulum or ramp test methods anytime in the near future.

Slip resistance and surface roughness

• None of the publications referred to in the Further reading section below provide any really definitive answer to the practical relationship between slip resistance values and surface roughness when assessing the suitability of a particular flooring material in a particular situation.
• The closest that we've found to an answer is that the slip resistance should be the determining factor in a new installation, and the relevance of surface roughness is (a) in assessing the slipperiness of the surface when wet or contaminated, and (b) as a method assessing the wear of a particular surface over time.

Further reading

• BRE. Information Paper IP 10/00. Flooring, paving and setts - Requirements for safety in use. 8 pages. Published 2000.
  The research concentrated on natural stone products but the paper has information relevant to all surface materials. Available from the BRE Bookshop at http://www.brebookshop.com/details.jsp?id=30041.
• British Standards Institution. BS 7976-2:2002. Pendulum testers, method of operation.
  Not, strictly speaking, essential reading but now generally agreed as the definitive UK test method. It is referred to in all the other publications listed here.
• CIRIA. C652 Safer surfaces to walk on. 254 pages. Published 2006.
  This is currently the definitive publication on the subject, written by Ove Arup & Partners under contract to CIRIA and part-funded by the HSE. There is a link from this page of the HSE website - http://www.hse.gov.uk/slips/information.htm - to the Publications page of the CIRIA website but the PDF download is only available to CIRIA members.
• Health and Safety Executive. The assessment of pedestrian slip risk. 9 pages. Published 10/04.
  This is by far the most concise starting point and is available free from the HSE website at http://www.hse.gov.uk/pubns/web/slips01.pdf or from this attachment.
• UK Slip Resistance Group. Guidelines Issue 3. Published November 2005.
  More information is available from their website at http://www.ukslipresistance.org.uk/guidelines.php.

© 2008-9. ArchiMentor.