Why do slip, trip and fall accidents occur?
Technically speaking, a slip occurs when the coefficient of friction (COF) between the shoe material and the walking surface does not provide sufficient resistance to counteract the forward, resultant forces at the point of contact.
This happens most commonly on wet floors or surfaces because water — unlike air — does not easily compress and, when trapped between shoe and floor, can form a continuous film leading to hydroplaning.
Of course, hydroplaning is more common in environments where water is regularly present, such as entranceways during inclement weather, shower rooms, lobbies and kitchens or food service areas.
According to the U.S. Department of Energy (DOE), a study of workers at DOE facilities who experienced injuries from slips and falls showed that approximately three-fourths of the indoor events reported involved water.
Since a floor that is slip-resistant when wet will generally be slip resistant when dry, taking measurements of the condition of floors by benchmarking the wet COF — a number or range indicating the slip resistance of the floor surface when it is wet or contaminated — is an important starting point to raise safety levels.
Measurement Overview
There are three steps to slip and fall prevention involving wet COF measurement and data collection:
Slip and fall prevention and COF measurement science have greatly progressed as of late.
Until recently, the goal was to achieve and maintain a .5 static coefficient of friction (SCOF) on a dry floor surface.
However, laboratory and field research have led to new, emerging and more practical benchmarks, since it is now clear that slips occur most often on wet floors in dynamic "in motion" environments.
Establishing A Foothold
If an existing wet floor''s SCOF demonstrates that it is slippery, consider applying a specialized treatment or product to the surface that increases wet slip resistance.
Two product categories have proven effective in raising slip resistance on wet surfaces and, thus, provide an excellent means to help ensure floor slip safety in general:
Surface modifiers use chemical processes to alter the physical properties of an unfinished mineral-containing floor or surface, improving the SCOF.
The process creates micro-pores or imperceptible tread patterns, rendering tile and stone floors safer to walk on when wet.
Applying a penetrating sealer makes the surface more resistant to soil.
Slip resistance lasts several years with proper, regular cleaning, and application should be handled by trained professionals.
Surface modifiers are also very effective on porcelain or ceramic tubs and showers.
• Mop-on cleaners/treatments
Mop-on cleaners/treatments are high-performance pH-neutral cleaners with ingredients that raise the slip resistance of finished and other floors.
Though recommended dilution ratios must be followed, relatively unskilled employees can apply these water-based treatments for routine cleaning and maintenance of slip resistance.
Follow Up Testing And Documentation
The initial SCOF test should form the basis and reference point for all future recordkeeping and follow-up testing.
This information should ideally be available both electronically and in hardcopy formats and should be readily accessible.
The results of all future slip tests should be added to the existing file the day the tests are performed or shortly thereafter.
According to Ludwin, "A walkway auditing program can help identify trends within your facility that can result in reduced slip resistance to flooring surfaces. To be effective, the testing should be completed in a consistent, periodic manner and include more than a single set of measurements."
Documentation should also include a guide and logbook outlining all standard cleaning procedures, the cleaning materials and equipment that are used and the recording of any slip and fall incidents — and the surrounding circumstances — that occur in the building.
A written and enforced floor safety policy and procedures guide will improve floor safety, while demonstrating management commitment to prevention.
The policy/guide should address common causes of slips and falls, such as poor worker training, lack of weather contingency planning, inconsistent hazard identification, inappropriate footwear and improper cleaning of floors, among other factors.
It should thoroughly detail how to perform and document wet COF measurement, improvement and maintenance of floors.
Kenneth Fisher is an advisor to the National Floor Safety Institute (NFSI) and serves on the B-101.1 Committee of the American National Standards Institute (ANSI), which recently established a test method for measuring wet static coefficient of friction of common hard floor materials. He is chairman of a sub-committee (ANSI B-101.2), which is developing a standard for chemicals and treatments for hard tile surfaces and also sits on the ANSI B101.3 committee establishing dynamic COF guidelines. He served on ASTM''s F-15 committee dealing with slip and fall issues. Fisher can be reached at Ken_Fisher@Nu-Safe.com or 1-859-493-0701.