Unreliable/Withdrawn Floor Slip Test Methods

ASTM C1028 SCOF test

The ASTM C1028 static coefficient of friction (SCOF) test was withdrawn (with no replacement) by the ASTM in 2014. SCOF testing in the wet condition has shown to have little relevance in predicting slip and fall accidents due to issues such as stiction and the fact that SCOF testing measures how slippery a floor is to someone who is standing still on it – not walking across it. More information on why this test is unreliable (in the wet condition) and was finally withdrawn by the ASTM (never to return) is available at C1028.info.

C1028 SCOF test in progress

ASTM C1028 SCOF test in progress

Brungraber Mark II

The now defunct and withdrawn ASTM F1677 used the Brungraber Mark II (also known as PIAST) test device (pictured below). ASTMĀ withdrew this standard in 2006 (only a little more than a year after passing the standard), with no replacement. One reason for ASTM’s withdrawal was poor precision in interlaboratory studies, meaning that everyone gets a different answer when testing the same tiles using this device. This tester and it’s withdrawn test method are therefore unreliable for assessing pedestrian slip risk.

Brungraber or PIAST

Brungraber Mark II

English XL – VIT

The now withdrawn and defunct ASTM F 1679 used the English XL Variable Incidence Tribometer (VIT), primarily for wet testing (pictured below). ASTM withdrew this standard in 2006 (with no replacement) shortly after passing this standard (in 2004). One reason for this standard being withdrawn was poor precision, which made different users get totally different answers when testing the exact same tiles. Results from this slip tester depend highly on how the button is pressed to initiate the test, and therefore wildly different results can be obtained depending on who is pushing the button. The English XL’s test results can be manipulated by experienced users by pushing the button slowly or quickly, which makes it a popular device amongst professional expert witnesses who can get the results the lawyer (paying his bill) wants to see to support his/her case.

English XL - VIT

English XL – VIT

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Periodic walkway slip-resistance audits of your floors by Sotter Engineering Corporation can significantly reduce the risk of slip-related injuries for everyone, while at the same time providing peace of mind and protection from frivolous or fraudulent claims based on an allegedly slippery floor.

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