Engineers Study Friction to Make Floors Less Slippery

A pair of engineers from the University of Pittsburgh (Pitt) is delving deep into the science of friction, in hopes of creating a floor surface that is significantly less slippery than a typical floor. The goal is to reduce the hundreds of thousands of slip and fall injuries that occur each year, as well as the billions of dollars of lost production due to such falls.

“Slips and falls in the workplace have an annual cost of $10 billion in workers’ compensation,” the press release announcing the project states. “This work is expected to lead to improved high-friction flooring that can help prevent these accidents and save both companies and employees the inconvenience of these injuries.”

BACKGROUND: SLIPS AND FALLS AFFECT US ALL

“The frictional relationship between two objects has beneficial effects,” the same press release states, “when you strike a match, friction lights a flame; when you use your vehicle’s brakes, friction helps bring it to a stop, This same relationship, when leveraged properly, can help prevent slips and falls in the workplace.”

According to the researchers involved, this is their exact goal.

“More than 140,000 workers suffer from fall-related injuries each year, and about half of them result from a slip,” said Kurt Beschorner, an associate professor of bioengineering and one of the two researchers behind this latest effort. “Designing specific, high-friction flooring could mitigate these injuries, but we need a better understanding of the flooring factors that lead to friction.”

ANALYSIS: MAKING THE GROUND LESS SLIPPERY

To try to improve this condition, Beschoner and fellow Pitt researcher Tevis Jacobs plan to use a recent award from the National Institute for Occupational Safety & Health (NIOSH), to measure the roughness of surfaces at the smallest scales ever measured. That’s because friction, or the lack thereof, is primarily governed by the relative topography of the two surfaces rubbing together. In this case, the shoe and the floor.

According to the press release, the team will then use those measurements “to build a model of friction performance with the long-term goal of innovating high-friction flooring to prevent occupational slips and falls.”

As Beschorner explained, “For this project, we will combine traditional measurements with metrics that can target smaller scales, including scanning electron microscopy.” 

This means that instead of using the traditional method of stylus profilometry to measure the topography of the floor, the duo will, according to Jacobs, be “cutting out a cross-section of the flooring and using electron microscopy, which can measure features that are one thousand times smaller,” than those seen by the previous method.

“These new measurements will allow us to establish the science behind roughness-dependent friction,” added Jacobs, “rather than just using trial and error to find the best surfaces.”

OUTLOOK: MORE FRICTION MEANS LESS FALLING

“To date, despite research worldwide, no one has yet reliably connected flooring topography to friction measurements for flooring,” said Eric Astrachan, executive director of the Tile Council of North America in that same release. “This is the ‘Holy Grail’ for flooring design, where an understanding of measurable topography parameters — parameters that also affect aesthetics and cleanability — can be used in the design phase to engineer flooring slip resistance.”

“Dr. Beschorner and Dr. Jacobs at the University of Pittsburgh are uniquely qualified to conduct this research that can directly impact worker and consumer safety, a key priority of the Tile Council of North America and our member companies,” added Astrachan. “It is our pleasure to facilitate this research through direct connections to the TCNA Product Performance Testing Laboratory and to the research and production departments of our members.”

Follow and connect with author Christopher Plain on Twitter: @plain_fiction