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Slip Resistance

Dry Testing Results Interpretation Guide

Interpreting Dry Test Results

How to interpret your dry test report

Dry test results offer two possible outcomes: classification 'F' or classification 'G'.

The classification 'G' reflects a less slip resistant surface, while the recommended 'F' classification reflects a greater slip resistant surface.

Step 1
Note the test location described in the left side column of your report, and the corresponding test result classification achieved (listed in the far right side column).
Step 2
If the test result classification listed is 'F', the test surface is meeting the relevant recommendations.
Table 3: Classification of pedestrian surface materials according to the dry floor friction test
(Notional contribution to risk)
Test Result Mean Value
F (Moderate to Very Low) ≥ 0.4
G (High to Very High) < 0.4

Treatment Options

For test results that achieve a result below recommendations, the following treatment options are available to increase slip resistance and Reduce Your Risk!

While ISTS is solely an audit service, following is a short list of common types of treatments we see our clients using to improve the slip resistance of various pedestrian surface materials.

Cleaning procedures
Minimising detergent residue build up or other contaminants.
Acid etching
Increasing surface texture.
Coatings and sealers
Surface coatings and penetrative types.
Surface texture
Coatings, etchants, sandblasting, shot blasting, etc.
Surface replacement
May be the most cost effective option in some instances.

An internet search for 'flooring treatments' will identify surface treatment professionals in your local area. ISTS recommends sourcing a number of detailed proposals when considering treatments, outlining expected slip resistance improvements, visual changes, clean ability and life expectancy.

Frequently Asked Questions

  1. The mean test average is ≥0.40, however the reported result is a 'G' classification.

    A: The mean of the test results should be equal to or greater than 0.40 and each individual result should be equal to or greater than 0.35. If either of this criteria is not met, the lot shall be considered to be ‘G' classification’.

  2. What does * and ** indicate?

    • * Indicates part of a test run registered under 0.40.
    • ** Indicates part of a test run registered less than 0.35 resulting in a compulsory 'G' classification'.
  3. Why are test results rounded to the nearest 0.05?

    A: As described in the relevant standards, the mean result of Test 1 & Test 2 is rounded to nearest 0.05.

  4. What is the classification requirement for particular locations as stated in publication SS 485:2011 Annex B?

    A: The New Zealand testing standard indicates floors should have a dry floor friction classification of F unless normal usage dictates that the floor should have a low dry coefficient of friction, eg. dance floors.

  5. How about dry testing for external areas?

    A: Dry slip resistance measurement does not apply to external surfaces. If a pedestrian surface is likely to become wet and remain wet for any significant period of time, wet pendulum testing is the appropriate test method.

  6. How do I improve the slip resistance of a surface achieving 'G' classification?

    A: Many treatments and procedures are available to improve slip resistance. Treatment options will vary depending on the type of surface and whether a sealed or unsealed finish is required. Described on the right are a list of options to improve slip resistance and Reduce Your Risk!

Additional Notes & References


*TABLE 1 – HB197:1999 "An Introductory Guide to the Slip Resistance of Pedestrian Surface Materials" CSIRO 1999 and Standards Australia 1999

*The information provided is intended as a guide only, consult the referenced publications for further information in regards to measurement results and recommendations.