Testing and measuring

What's the best way to test slip resistance?

These are the most common and reliable methods of testing slip resistance. At Altro we combine all of them to get the most accurate proof of just how safe our flooring is.

The TRRL Pendulum Test (BS7976)

The 'pendulum' is a swinging, dummy heel that sweeps over a set area of flooring in a controlled manner to simulate slipping on a wet floor. The slipperiness of the flooring has a direct and measurable effect on the pendulum value. Flooring that achieves a wet result of ≥36 on the Pendulum Test has a low slip potential.

All Altro safety flooring for shod areas exceeds the ≥36 rating, indicating the lowest potential for a slip.

In most cases both TRRL Pendulum Coefficient of Friction (CoF) and Surface Microroughness readings are needed to give an accurate indicator of floor surface slipperiness.

Surface Microroughness Meter

The total surface roughness of flooring materials is measured using a microroughness meter, which measures in Rz microroughness values (microns). It traces a needle over different areas of the flooring, taking peak to valley measurements to calculate surface microroughness. A surface roughness of 20 microns or above implies a low slip risk.

The Ramp Test (DIN 51130)

The Ramp Test is widely used, and its 'R' values are quoted by most flooring companies. R9-R13 values are based on angle measurements of a motor oil-covered ramp that an operator walks on. The angle at which the operator slips forms the R value, but because the most common contaminant on floors is water, using oil doesn't give a true representation of what happens in real life situations. We quote R values for our products because some of our customers are used to working with them. But we believe the values don't always provide clarity of slip potential and that the categories of values are too broad.

Why the Ramp Test can be confusing…R9 Is Not Fine!

It's often assumed that the scale of R values starts at R1 and ends at R13 – R1 being a measure of the greatest slipperiness. So an R9 value is often thought to indicate a surface that provides good slip resistance and some manufacturers don't try to dispel this misunderstanding. The truth is that R values start at R9, and it indicates the least slip resistance. R values don't tell you the whole story. Only where you see R10 AND a corresponding TRRL ≥36 together , like on Altro sample cards, can you be sure of the slip resistance of the product.

SATRA Pedatron Test Machine STM 528

The SATRA Pedatron Test measures the effect of one million steps over a confined area of flooring, using a shoe with standard sole. It's used to measure flooring surface wear. Accurate wear patterns are produced by studying and replicating different walking gaits, incorporating straight and turning steps.

At Altro, we invest in this test as yet another accurate way to measure sustained slip resistance.

Health and Safety Executive Slip Assessment Tool (SAT)

You can download free software at www.hse.gov.uk/slips which helps you carry out a risk assessment with a surface microroughness meter, so you can get a slip risk classification for a floor.

European Tests

These two tests are:

• EN 13893 – a pull sled test where the requirements are a coefficient of friction of >0.30
• EN 13845 Annex C – a ramp test similar to DIN 51130 and DIN 51097 using water and soap as the contaminant

EN 13845 – what the results tell us

This test measures slip resistance by counting particles over a given area on an ex-factory flooring sample. If it passes, the flooring can then be classed as either Enhanced Slip Resistance Footwear (ESf) or Enhanced Slip Resistance Barefoot (ESb).The number of cycles reached indicates what building use classification is achieved. After 50,000 cycles the flooring is suitable for the top classification of 34/43, which is very heavy commercial and very heavy industrial respectively. All Altro safety flooring passes the 50,000 cycle test classification.

Test results combine the ESf or ESb with the number of cycles indicating the level of sustained slip resistance. We recommend that whenever this information isn't provided, you should ask a manufacturer for the specific number of cycles that the flooring has passed as an indicator of that product's level of sustained slip resistance.

Manufacturers like Altro have to pass these standards to claim that their flooring is slip-resistant and can be sold in European countries.

What do the results of slip resistance tests actually mean?

Some manufacturers send ex-factory materials to independent test houses to certify that their products are slip resistant. This means the results can be based on flooring that has a thin coating or emboss which was applied to increase the level of slip resistance for the test. We, and some other British safety flooring manufacturers, believe that these thin levels of slip resistance can wear off in just a few months. And this leaves a much less slip-resistant surface which could fall significantly below the HSE minimum recommended level of TRRL ≥36.

If this happens, the floor could be unsafe. Which is why here at Altro we believe that the only true way for a floor covering's performance to be measured is when it's already installed.

'Polyvinyl chloride floor coverings with particle based enhanced slip resistance – Specification', is the test for the European standard that covers safety flooring. To be classified as a PVC safety floor, we believe the product must conform to this standard.

The only reliable way to test slip resistance

Altro are a member of The United Kingdom Slip Resistance Group, who believe that the best way to measure slip resistance is to use the TRRL Pendulum Test. We believe this too and it's also the preferred method of the Health and Safety Executive. It has several advantages over the Ramp Test, the biggest being that it can be used to measure in situ floor coverings and therefore sustained slip resistance, which will tell us if we can classify the product as true safety flooring.