The HSE in conjunction with its own laboratories, the Health and Safety Laboratories (HSL) have carried out over many decades proving of the test equipment and the methodology and arrived at parameters recognised across the UK. It has published hundreds of papers on the topic and it works in conjunction with other leading industries to develop safe floor and safe working practices including the (UKSRG) United Kingdom Slip Resistance Group and the likes of the UK Building Research Establishment.
The Pendulum Test Equipment is built in the UK to EN-16165 (formerly BS-7976-) and precisely Calibrated Annually in accordance with EN-16165 mentioned above
The Pendulum Rubber Sliders used and some of the calibration mediums are also subject to a 12-month expiry limitation. The sliders dictated in EN-16165 and BS-7976-2 and the UKSRG Guidelines when the test was performed are IRHD (International Rubber Hardness Degree) #55 or #57 (softer rubbers) and #96 (harder rubber).
Slider #96 is typically used to emulate the shod environment.
Slider #55 / #57 is typically used to emulate the barefoot environment and on profiled surfaces particularly where a surface is too rough / profiled to effectively use slider #96 as the harder rubber has a tendency to skip / judder on some surfaces affecting the outcome of the results.
Where both sliders are used (55 and 96) for example in a swimming pool changing room where both bare foot and shod feet will be present, then it is always recommended to use the lowest value achieved as the final test result; the UKSRG Guidelines state also, on profiled surfaces. Using both 55 and 96 might help the user to understand the range of behaviours seen with different footwear (some footwear also has profiles soles / heels; some are smooth.). The UKSRG Guidelines also state profiled surfaces should also be tested with 55 and 96 sliders on the basis that profiles can give a wide range of slip resistance values.
Slider #96 is not temperature sensitive but slider #55/57 are. Adjustments both up or down to the PTV values must occur depending upon the ambient temperature at the test location, the adjustments vary for different standards, read the section on Rubber Sliders
Floor Slopes away from a horizontal surface will affect the ability to resist slips so the standards / guidelines inform an adjustment must occur. The mathematical calculation is the value 100 x tangent ‘a’ where ‘a’ is the slope angle. In more simplistic terms, a nominal nearly accurate value of 1.75 PTV (rounded up to the nearest integer) can be adjusted for each degree of slope.