Evolution of the Australian slip resistance standards

AS/NZS 3661.1 - Slip resistance of pedestrian surfaces

Published in 1993, AS/NZS 3661.1 was the first Australian Standard for the Slip resistance of pedestrian surfaces. The standard specified the minimum coefficient of friction values under WET and Dry conditions. A surface with a coefficient of friction equal to or greater than the minimum specified value of 0.4 (or 40 BPN) was considered slip resistant. Ramps and other sloping surfaces required an increased minimum coefficient of friction according to a formula in clause 5.2. The greater the slope, a higher coefficient of friction being required.

AS/NZS 4586 1999 - Slip resistance classification of new pedestrian surface materials

AS/NZS 4586 established a new philosophy, rejecting the concept of a universal minimum slip resistance threshold irrespective of their intended use. Instead AS4586 introduces the concept of considering all underlying variables including an understanding that slip potential is a function of footwear, activities, gait, contamination, environment and other factors. The WET Pendulum test  results being classified in terms of the 'contribution  of the floor surface  to the risk of slipping  when wet'.

AS/NZS 4586 both acknowledges the pedestrian contribution to the risk of slipping and also the nature of the anticipated activity and the probability of a range of contamination conditions. It intrinsically recognises that there is a significant difference between the type of flooring that would be safe, for example, in a large commercial kitchen and that in a domestic kitchen. See table below:

HB 197:1999 - An Introductory Guide to the Slip Resistance of Pedestrian Surface Materials

This Handbook was prepared to assist in the use of AS/NZS 4586:1999 and specifying pedestrian surface materials for various locations. The Handbook does not provide any interpretation of dry slip resistance test results. The AS/NZS 4586 wet pendulum classification system is based on a risk management approach rather than one size fits all approach of AS/NZS 3661.1. The Handbook states that “one should not presume that the recommendations in this Handbook provide a guaranteed solution for every circumstance”.

The Handbook provides recommendations for pedestrian surface materials in various common building locations. In providing this advice the Handbook states “Other design considerations include the amount and type of expected traffic (vehicles, trolleys, people hurrying, elderly, disabled people with or without walking aids, and children); the product characteristics (wear resistance and cleanability) and the consequences of exposure to the types of contaminants that might be anticipated; 

AS/NZS 4586: 2004 - Slip resistance classification of NEW pedestrian surface materials AND AS/NZS 4663:2004 - Slip resistance measurement of existing pedestrian surfaces

“A new floor is considered to become an existing floor once it has been installed and made available for pedestrian traffic, other than movements specifically for purposes of formal testing to determine compliance with this Standard. Testing of existing floors is covered in AS/NZS 4663, Slip resistance measurement of existing pedestrian surfaces”.

Classifications and interpretation of WET Pendulum results remain the same as first published in AS/NZS 4586 1999 - Slip resistance classification of new pedestrian surface materials. This includes reference to interpreting these standards in conjunction with the Handbook HB197.

AS 4586-2013 - Slip Resistance Classification of New Pedestrian Surface materials AND AS 4663-2013 - Slip Resistance Measurement of Existing Pedestrian Surfaces

This revision incorporates an additional requirement for preparing rubber sliders on testing instruments when testing smooth surfaces and changes to the nomenclature for classifying surfaces. The adoption of a lapping film (very fine abrasive) may result in some smooth surfaces receiving lower classifications.

The new nomenclature for classifying surfaces based on their BPN in outlined in the table below. TABLE A2.3 – Classification systems from AS/NZS 4663:2004 and AS4586:2013

Note 1: Font in purple is from AS/NZS 4663:2004

Note 2: Contribution of the floor surface to the risk of slipping when wet has been removed from the 2013 standards

SA HB 198:2014 - Guide to the Specification and Testing of Slip Resistance of Pedestrian Surfaces

The updated handbook was published in 2014 and introduced changes outline some of the changes which were introduced to the new 2013 slip testing standards: As well as outlining changes to the way in which the testing methods have been altered, the Handbook contains Table 3A – “Minimum WET pendulum or oil-wet inclined platform classifications that are deemed to satisfy the building applications in the National Construction Code (NCC). NCC compliance is demonstrated by achieving the values set out in this Table.”

Prior to 2014, the NCC Provisions for slip-resistance were drafted using qualitative language that essentially reflected the Performance Requirement. However, amendments to the DTS Provisions included in the NCC that came into force on 1 May 2014, specified slip-resistance classifications for:

  • landings and ramps in Class 2-9 buildings; and
  • stair treads or nosings to treads for all classes of buildings.

The DTS Provisions in NCC 2014 required treads or nosings to treads of a stairway, and for certain buildings the surfaces of ramps and landings, to comply with a slip resistance classification specified in the NCC when tested to the 2013 edition of AS 4586 ‘Slip resistance classification of new pedestrian surface materials’. This requirement applies to all finishes and surface types (including carpet, tiles, timber, vinyl, concrete and metal). Other notes to consider in HB 198 which was also outlined within HB 197:1999 is that factors relating to a slip and fall are not always a direct result of the frictional characteristics of the floor. Other factors include:

  • Lighting, including luminance contrast
  • Age, gait and nature of the pedestrian activity
  • Gradients & sloping surfaces
  • Type of contamination, oil, water
  • Footwear, soling material, trad and fit
  • Handrails, barriers and balustrades
  • Stair geometry and dimensional consistency
  • Cleaning, wear, maintenance and residues

This is why there are limitations in HB 198 which outlines that it is for general guidance only and that as there are almost always a complex interaction of factors, even specifying and ensuring surface achieve the recommendations, it will not stop incidents from occurring.