The most popular glazing product used in Canada is a single layer of plastic, a material called polyethylene terephthalate (PET), according to the Canadian Institute for Occupational Safety and Health.
But some experts say the substance used in glazing should be considered safer.
“The use of polyethylenes in Canada should be restricted to those with approved safety documentation,” said Alana Vauch, an occupational safety and health specialist at the University of Ottawa.
“Polyethylenes are highly flammable.
So, it’s very important that you have a fire-resistant polyethylenimine or polyethylbenzene-based flame retardant.”
The federal government says there are more than 100,000 safety documents in place to ensure that workers can safely use plastics.
But there are questions about whether the safety protocols are being followed.
The federal Occupational Health and Safety Board is also investigating.
Vauph said it’s also important to look at the chemicals in the products and the levels of exposure.
“If you have one or two of these chemicals, the risk is increased, but the potential benefit is also increased,” she said.
“What we need to know is what the actual health risks are and if there are risks that are greater than the risks that you’re really exposed to.”
The study, conducted by the University’s Faculty of Engineering, tested six types of polycarbonate glazing, including a single sheet of PET.
Each product was tested using a variety of different flame retardants.
They were also tested for their toxicity.
The study found that the polycarbonates had a safety record of 97 per cent, while the fire-retardant products were 99 per cent.
One of the fire retardants was found to be 100 per cent toxic.
The results also showed that polycarbonated glazing has a higher rate of fire and water entry than other types of glazing.
The research, which was published online last month in the journal Occupational and Environmental Health, found that fire-resistance was a factor in a significant number of the pyroclastic flows that occurred.
The polycarbonatess were found to contain polyvinyl chloride (PVC), which can cause toxic fumes, and polyethylacrylonitrile, or PE, which is an ingredient in polyurethane foam.
The materials are known to have high levels of flame retardancy and toxic fumes.
A report published by the International Agency for Research on Cancer (IARC) in 2013 warned that polyethylacetone was linked to cancer, and that polypropylene foam could be linked to lung cancer.
“PVC foam is a high-end product that can be used to protect against fire, particularly when it comes to outdoor lighting,” said David Kravets, a University of Toronto professor who is an expert on plastics.
“It is not a very good choice when it came to fire safety because it can be a very reactive material.”
But Kravet said he believes polyethylane foam can be better used in situations where fire is more of a concern.
“I think it’s the best option for use in fire protection,” he said.
He also thinks the flame retardency of polypropene foam is probably higher than that of other types.
But, he said, “the flame retardation of polystyrene is very low.”
Another study found polyethyleneglycol, a foam used in many products, had a flame retardance of 94 per cent and had a fire resistance of 97.5 per cent compared to the other types tested.
“These types of flame-retaining compounds are used in a variety or applications in different countries,” said Professor Kraveys.
“They’re not in high demand or in widespread use, but they’re not bad ones.”
Kravech said the risk of exposure to polyethylpropylene, PE and other flame retardents is a big concern for the general public.
“We have a lot of plastic waste in our country and we are not getting the material to use responsibly,” he added.
“So, that’s something that we need as a society to look out for.”
But Vaucher said plastic foam is also used in products that are more flammible.
“For example, polystyrenes, which are a very flammant product, have a flame-resisting capability,” she explained.
“That means they’re more of an issue for outdoor fires because you’re going to get a lot more flamable stuff.”
But she said there are other products, like foam, that are safer to use.
“In a lot that we’re using these products for, it doesn’t matter whether it’s plastic or foam, the fire safety is still important,” she added.