OHS Canada Magazine

Donning for Danger

February 11, 2016
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By Jeff Cottrill

Protective apparel is a broad category that encompasses fire-resistant (FR) gear and garments, as well as clothing that shields workers from the elements. It also comes in a variety of forms, including frocks, jackets, overalls, gowns, laboratory coats and even high-visibility apparel.

The two primary markets for protective work clothing in Canada are businesses that need garments to protect against chemicals, hazardous materials, dust and dirt, and those in sectors requiring FR gear, according to Randy Hillmer, national sales manager with Lakeland Canada, a protective-clothing manufacturer based in Brantford, Ontario.

“Firefighting clothing is kind of the most technically advanced, if you will, of protective apparel,” says Hillmer, whose company specializes in disposable clothing and garments protecting against chemicals, heat and fire. He adds that employers need to consider all the hazards in an environment before deciding what types and brands of protective clothing to acquire.

“They are going to fall into one of those classes where it is going to be a chemical hazard, or it is going to be a flame hazard, electrical hazard,” he says. “They really need to consider clothing the same way you would consider respiratory protection or glove protection.”

The specific protective clothing that an employer must look for depends a lot on industry needs. The oil and gas industry uses coveralls, plus a lot of outerwear like jackets, parkas and sweatshirts. Electrical workers also need basic protective gear, often shirts and denim jackets, while research laboratories and similar environments where workers deal with chemicals and other caustic materials tend to wear traditional lab coats.

Under covers

According to the Canadian Centre for Occupational Health and Safety (CCOHS) in Hamilton, Ontario, the selection of materials and fabrics for protective clothing is just as diverse. A multilayer laminate of polyethylene and ethylene-vinyl alcohol can protect a worker against many chemical exposures, while Nomex, an aromatic-polyamide (aramid) fibre, is a common choice for resisting high temperatures and industrial chemicals, for example. Tychem is a tear- and puncture-resistant material, while Kevlar is another aramid fibre known for its protective strength against cuts, heat, flying fragments and even bullets.

Chemical-protective clothing often contains polymer or plastic film that acts as a barrier against specific or families of chemicals, Hillmer notes. “Certain plastics are going to be better for organic acids or inorganic acids, or hydrocarbons.”

The primary difference between chemical-protective clothing and standard FR gear is that the former is made of inherently fire-retardant material, explains Lyse Moreau, owner and president of International Sew Right in Niagara Falls, Ontario. “It has not been treated onto the fabric; it is right into the thread of the garment,” she says about anti-chemical gear, which is made of fabric that is woven, dyed and dipped in solution that is absorbed into the fabric, before one puts it through a dryer process.

In the United States, the Occupational Safety and Health Administration requires employers to conduct hazard assessments before donning workers with the necessary protection. In Moreau’s experience in Canada, firms tend to go by their own guidelines.

“Their health and safety area will have policies and standards that they have to adhere to,” she says, adding that her company occasionally receives detailed standard policies from clients who need a certain kind of protective gear. “And they will send me printouts of what the spec sheets are, and it can be up to 50 pages long,” Moreau reports. “They will specify that they want the surging to be done with the same type of thread, or that the stitches have to be so many per inch. And we have all the computerized sewing machines to do that here.”

In some cases, those who operate in environments containing more than one hazard, such as a worker who handles chemicals, may also need FR protection from flash fires, arc flashes or steam. Another way to use protective work clothing to guard against a variety of hazards is a process known as “layered” clothing, says Moreau, who lists several categories of layering that are standard in the industry.

“Category one, you can get away with wearing a shirt and pants. When you get into category two, and you are moving up higher, you have to get into what we call the layering effect,” Moreau says. “You have your garments that you were issued in the past, but then you will have your undergarments, long T-shirt, long underwear.” The higher categories, three and four, involve insulated clothing, such as those used for cold weather, she adds.

International Sew Right produces protective clothing of all kinds, including FR gear, high-visibility clothing and garments protecting from extreme temperatures. But its specialty is custom-designing protective work clothing according to employer requests, which means that the company sometimes needs to think outside the box — or outside the categories — when manufacturing original garments, especially when shielding workers from heat stress.

“We will get companies that will say, ‘I need to have something specifically designed,’” Moreau relates. “And then they want ventilations put in a certain area, so that the flow of heat that is occurring inside the coat has a way of getting out, and we will design it whichever way they want.”

Heat of the moment

Heat stress is an important issue to consider with protective clothing, especially for firefighting and chemical-protective apparel, Hillmer points out. The plastic and polymer film in anti-chemical garments tends to be part of the problem. “If you have a serious chemical hazard, then heat stress can become an issue, because chemical-protective clothing does not offer any kind of breathability,” he cautions.

Saner says that a mix of air permeability and moisture management, or the ability to absorb sweat rapidly, in a fabric is the best way to relieve heat stress. “You want fabrics that have high degrees of air permeability, so you get a lot of airflow that can go in and out, allow the heat out,” he explains. “You have some that will absorb moisture well, but they don’t dry very fast, and then you have some that will both absorb and dry quickly, and that is the ideal situation.”

Pricing is determined by the make of the garment, according to Moreau. “When you get into a fabric that is 100 per cent cotton, compared to one that is fire-retardant, or inherently fire-retardant, you are talking a lot of money per garment,” she notes. The price ranges anywhere from $70 to approximately $200, depending on the specifications required. “Your cotton and your poly-cotton are your two cheapest to go by.”

Cotton and poly-cotton clothing are most commonly used for high-visibility garments in the paving industry, she adds. “They will use the high-viz orange 100 per cent cotton or the poly-cotton that will protect them so that they can be noticed, but they don’t need the fire-retardant.”

Out with the old

Hillmer says that much industrial chemical-protective clothing is designed to provide “limited-use” wear. “Limited use is designed to be worn either until the garment is damaged or until it is contaminated,” he explains. “Essentially, it is a little bit more disposable, but it is really only designed to be used once if it is exposed to a chemical. Once the process of chemical penetration or permeation is standard, there is no way to stop it.” The only way to test the fabric to see if it retains its function as a protective barrier is to conduct destructive testing, which is counterproductive, he notes.

If a limited-use garment is worn without exposure to chemicals, it is best to clean the garment and make sure that it is dry before putting it away. “If you are going to fold it up and keep it in bags and stuff like that, it should be dried before it is folded,” Hillmer advises.

The CCOHS warns that no material can resist all chemicals, nor will any material be capable of resisting a specific chemical indefinitely. Some chemicals can permeate a fabric in a few seconds, while others may go through the same material in days or weeks. As such, it is vital to ensure that the material used is correct for the relevant chemicals and that regular inspections identify and replace garments before they become ineffective.

Jeff Cottrill is the editor of Canadian Occupational Health & Safety News.

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