Heavy woolen and fleece clothes may help Canadians survive the country's long and frosty winters. But many people don't realize that they also carry a hidden hazard: when tumbled in a dryer, they shed loads of lint that can pack into cavities and exhaust pipes and increase the risk of fire.

There are about 12,700 clothes-dryer fires in residential buildings annually in the United States, according to the U.S. Fire Administration. These preventable fires caused 15 deaths, 300 injuries and about $88 million US in property damage. There are no comparable statistics available for Canada.

Marla Friebe, the acting information officer for the Toronto Fire Services, said Canadians in particular must be vigilant about maintaining a lint-free clothes dryer because of our long, slushy winters.

"In Canada, we use our dryers probably excessively," Friebe said. "If you're anything like my family, we're doing two to three loads of laundry every day, so I make sure I clean my trap every time with every usage."

Failure to clean out lint traps is the main cause of dryer fires, according to Friebe. A blocked vent or exhaust pipe blocks hot air from release, turning the highly combustible lint into a fire hazard.

Friebe says consumers must check both the lint trap and the pipe for lint.

"Sometimes there's moisture in the air and [the lint] tends to stick so essentially it means regular cleaning out of both the trap and that particular exhaust pipe."

Friebe recommends people use their vacuum cleaner to clear out lint buildup in the dryer.

Safety tips:

How to ensure you don't have a dryer fire:

• Never put mops or rags that have been used with a wax, flammable solvents or oils in the dryer. The Ontario Fire Marshall cautions that even if these objects have been cleaned, they can still catch fire in the dryer.
• Never put any items lined with natural or synthetic material, such as rubber-soled running shoes, in the dryer. Foam pillows or clothing with foam padding should also be left out to air dry.
• If your clothes are taking longer than normal to dry, check for blocked pipes or lint buildup. If the unit is clean, the heater coil on the unit may be malfunctioning.
• Replace ripped filters or cracked exhaust vents.
• Choose aluminum or steel ducts over vinyl hoses, which can droop in certain areas creating pockets that might trap lint. Plastic ducts can also melt or collapse and fail to contain the fire within the unit.
• In the winter, make sure that dryer vent flaps are not freezing shut or sticking.
• Liquid fabric softener boosts the burning speed of all-cotton clothing including fleece, terry cloth and velour, according to the consumer watchdog Consumer Reports. Use dryer sheets for these clothes instead.
• Don't leave your dryer running unattended because the shut-off switch can fail, causing the dryer to run continually. As an added safety precaution, be sure to place a smoke detector in the general vicinity of the dryer.
• Keep the area around the dryer clear of flammable materials.
• Make sure the dryer is plugged into an outlet with sufficient power.
• A blocked vent will cause the dryer's high temperature safety switch to continually cycle on and off, which can lead to early failure.

Fabric-sheet film buildup: fact vs. fiction

According to chain e-mail legend, an unnamed person claimed to have been warned against the use of fabric sheets because they produce an invisible film on the lint filter.

The e-mail warned that since the transparent film may cause dryer units to catch fire, consumers should regularly wash their lint traps in hot soapy water.

Consumer Reports evaluated the advice in the e-mail and suggested that over time, fabric sheets and softeners can leave a film on the lint screen.

Researchers with the consumer advocacy group noted that if people are concerned about the fabric softener residue, they should clean their filter with warm soapy water and a brush. But, they cautioned that it was "highly doubtful" that the film alone would lead to a fire.

Buying a new dryer

When buying a new unit, choose an energy-efficient model equipped with moisture sensors that stop the machine automatically when the clothes are dry.

Older dryers with thermostats run for a set period of time, sometimes longer than needed.

The Ontario Fire Marshall's office recommends that clothes dryers placed in closets or enclosed rooms should have an opening of at least 775 cm² to ensure good air flow.

In many new homes, clothes dryers are often placed in non-traditional areas such as the bedroom or an upstairs closet. In these cases, long exhaust pipes are used to allow for air flow. Friebe warns that maintenance can be difficult with longer air flow pipes.

"Essentially it creates a lot of sharp turns and bends in the duct work and that just provides extra locations for lint to get trapped and it makes it really hard to get cleaned," she said.

Also, be sure to read the accompanying manual and call on a service technician to repair the unit. Friebe says consumers should call a technician to take their dryer apart every one to three years.

"Lint can literally get trapped everywhere inside a dryer," she says.

[an error occurred while processing this directive]