Ergonomics, ability to drain liquids, heat-resistance may also need to be considered
When the owners of ICON Safety Consulting in Camrose, Alta., were deciding on the kind of flooring they should put in, they had two main considerations in mind: the expected foot traffic and Alberta winters.
“We figured, it is a concrete floor. It’s going to get slippery with snow and mud. So we decided to put in mats that are removable and cleanable,” says Jodi Tetz, general manger at ICON Safety Consulting.
“We also decided to go with heavier, really good mats, so they don’t roll and cause a tripping hazard. We wanted to make sure the mats themselves couldn’t slide and cause a hazard. Particularly because we’re a safety place, we didn’t want tripping hazards.”
Slips and trips occur in all industries and are among the most common causes of workplace injuries. In many cases, the floor surface is an important factor in the incident: floors may be uneven, wet or dirty; carpeting or mats may be unsuitable, loose or damaged. Knowing what kind of flooring will prevent slips and trips and is best suited to the conditions of a particular workplace will help reduce injuries.
Most types of flooring are relatively slip-resistant when dry. However, any contaminate — water, dust, oil or solvents — can substantially reduce the non-slip effectiveness. Traction is also greatly reduced when a surface, like concrete, vinyl and timber, has been polished. Worn surfaces, which are especially a problem with steel and concrete, will increase slipperiness. In general, the duller a surface is, the more slip-resistant it is.
Before choosing anti-slip flooring, companies should make sure the product has been properly tested, says Erick Schuetz, vice-president of sales and marketing at Streetsboro, Ohio-based Safeguard Technology. Slips occur where there is too little friction or traction between the footwear and walking surface. The slip-resistance of flooring is established through laboratory testing and is expressed in terms of its “coefficient of friction” (COF). The higher the value, the less slippery the surface. Generally, a COF of 0.5 is recommended, although some work tasks may require a higher COF. Flooring should be tested when the surface is not just dry and flat but also with water, oil and on an incline to simulate a ramp.
What gives flooring its slip resistance is its grit (or aggregate) surface, which provides traction through the presence of hard, rough edges that grip footwear. This grip is sometimes created by quartz or silica sand (such as in coatings and tapes) or aluminum oxide. However, due to its durability, the component most often used to create grit is epoxy; it is the preferred grit in industrial, commercial work sites. Where finer grit is required, a variety of materials are used, including alkyds or acrylics.
This top, grit layer is affixed to a base material, commonly PVC (vinyl), steel or aluminum. Fibreglass is also used, particularly where there is heavy traffic, says Nigel Altman, president of Toronto-based No Skidding Products. Common applications are in mass transit and heavy industrial sites, including factories, where oils and hydraulic fluids are used.
MATS AND TILES
Anti-slip mats and tiles, which may be interlocked to fit together during installation, are usually made of rubber, PVC or polyurethane and have a grit surface of a hard substance, such as silicon carbide. Traction may be increased by the use of knobbed, ribbed or corrugated top surfaces — useful in workplaces, such as food processing plants, where there is a lot of grease in the environment.
“If you drop grease on something that is completely flat and smooth, then it smears out and can become very slippery. But if you drop grease on something and there is a centimetre or so of very small knobs, the grease will fall down in between the knobs, away from the surface,” says Hans Lofgreen, president of Jenelex in Toronto.
To reduce the risk of tripping, mats often have bevelled edges: The edges incline gradually to the floor. (Bevelled edges can also be added to tiles.) In contrast, standard mats and those that come in rolls and are cut to measure have raised edges that may cause trips. They can also become dog-eared, and the curled corners can cause a worker to trip.
Anti-slip mats and tiles are often constructed to raise the worker up off the wet, slippery floor and, at the same time, allow spilled fluids to drain down through holes or deep ridges while the grit surface stays dry.
FLOOR AND STEP COVERINGS
Non-slip surfaces can be created on flat walkways through the use of coverings. These can be customized to fit different area lengths and widths and are attached to the substrate by mechanical fasteners or adhesives. The gritted surface ranges from very coarse (for extreme environmental and traffic conditions, such as off-shore oil rigs) through fine (for commercial spaces) to very fine (for more protected indoor conditions, such as shower areas).
Floor coverings are mostly commonly used in the oil and gas, transportation and food processing industries, as well as in chemical and oil refining facilities, Schuetz says.
Colour can be used to increase the non-slip effectiveness of a covering or mat, he adds. On steps, for example, it is a good idea to use two contrasting colours to increase workers’ ability to distinguish stair edges. In manufacturing facilities, colour helps identify the safe path walkways designated for office staff and visitors. The main colour of the covering may be green while the edges are bright yellow.
Using colour also helps reduce incidents that happen when people move from a regular floor area onto anti-slip flooring, Schuetz says.
“All of a sudden, they may catch their foot or they may stick and their momentum pulls them forward. So it’s always important to call out by colour a difference in profile and texture.”
Anti-slip floor coatings, or paints, are particularly suited to large areas and are applied onto conventional flooring, such as concrete, wood and metal, Altman says. They provide substantial traction and are often used in industrial, factory and warehouse workplaces, where work boots are worn and there is forklift or pallet-truck traffic. Coatings, which can be used on interior and exterior surfaces, create a visible, textured surface. They may be clear or coloured.
In contrast to coatings, which create a surface texture on top of the substrate, non-slip treatments contain a chemical that increases the roughness of the floor surface.
“They create a microscopic tread on the face of the tile. Then, when that tile gets wet, the tile creates a suction-cup effect to help grip the foot on the substrate,” says Altman.
Treatments can be used where street shoes are generally worn. They are typically applied to hard surfaces that become extremely slippery when wet. Common applications are ceramic, granite, terrazzo and vinyl, as well as concrete and porcelain tile. The coating increases the COF and thus the traction of the floor surface.
With treatments, the floor retains its original appearance. This makes them an attractive option for businesses and organizations that serve the public, such as offices, banks, stores, hotels, governments, schools and transit.
One advantage of coatings and treatments is they eliminate the trips that happen due to a change in floor surface, which a mat or carpeting might cause, Altman says.
“If someone is walking from one flooring type to another and there’s a change in the slip resistance or COF, this can result in a slip and trip because they are in their stride. Consistent flooring type is key with selecting flooring types.”
Coatings and treatments need to be maintained through regular use of proper cleaners and de-greasers to remove soil and debris that can reduce the effectiveness of the slip-resistant surface.
The big advantage of anti-slip tapes is they can be installed over irregular surfaces. Tapes, which come in different widths and lengths and in varying grit sizes and strengths, are commonly used on construction sites and scaffolding planks. They are especially useful on ladder rungs, wheelchair ramps, truck running boards, stairs (particularly those with vertical exit enclosures) and in shower areas. Tapes are an inexpensive, quick fix but must be repaired or replaced on a regular basis.
Different workplaces will require different anti-slip flooring solutions. In the municipal transport sector, especially subway systems, safety managers should consider that flooring must also be able to meet stringent fire retardant requirements. As well, entry and exit points should have photo luminescence for emergencies. Moreover, due to the high traffic, the flooring, as on bus wheelchair ramps, should be easily cleanable.
“When they clean their buses each night, they usually use a mop and a bucket of water. So if you have a high coefficient-of-friction-product, the fibres of the mop get in there. High COF products don’t stay clean very long,” Schuetz says. “If you’re purchasing a $700,000 fire truck, you don’t want the anti-slip on that to be dirty and always look bad. With municipal transportation, it’s always a balancing act between safety and aesthetics.”
Cleaning is also a major consideration in restaurants and food processing plants, where strict sanitation standards must be met. Grease and food residue can accumulate in slip-resistant mats. One solution is to consider selecting a finer grit grade. A company may also need to seal the perimeter of the covering with a moisture-cured urethane to eliminate bacteria or moisture becoming lodged under surfaces in a plant, where it might contaminate food.
Alternatively, food processing companies may prefer removable mats over fixed flooring. Because they can easily be taken away to be cleaned, it’s easier to make sure they remain free of spilled food and liquid. Some nitrile rubber mats can be sanitized in a dishwasher.
Another consideration is the cleaning regimen: Harsh chemicals can quickly degrade an aggregate surface.
“When they’re choosing anti-slip flooring, they must consider their cleaning method. If it’s a food processing plant that uses a high-temperature alkyd solution, think about what you’re going to put down as your anti-slip because it may not stand up to that,” Schuetz says.
In manufacturing and automotive plants, managers should consider selecting flooring that both prevents slips and trips and has ergonomic or anti-fatigue properties, Lofgreen says. Many non-slip mats are designed for workers who have to stand on hard floors for long periods of time. These help relieve stress in the back, legs and feet and reduce musculoskeletal disorders.
“When people stand on them, they give in a little and bounce back. That increases the circulation in the legs to reduce fatigue,” he says.
Some areas in manufacturing sites tend to be constantly wet. Thick, non-slip mats that allow oils and other fluids to drain down will prevent workers from standing on wet floors. These mats are often made to be heat-resistant to withstand chemicals and extreme heat.
Altman says it’s important to remember flooring is just one aspect of preventing slips and trips. He advises companies to be proactive and adopt a “systems approach” to preventing incidents. In addition to the selection of the flooring, the other essential elements of the system are proper footwear and regular housekeeping.
“Good housekeeping is critical because often slippery floors are the way they are because of surface contamination. So clean up spills quickly, sweep dirt off the floor and remove clutter and obstacles,” he says. “It’s not just about selecting a slip-resistant floor but also about ensuring that floor stays slip-resistant after it’s installed.”
Linda Johnson is a freelance journalist based in Toronto. She can be reached at firstname.lastname@example.org.
This article originally appeared in the October/November 2017 issue of COS.