The U.S. Consumer Product Safety Commission estimates that there are an estimated annual 15,500 fires, 10 deaths, and 310 injuries associated with clothes dryers. Some of these fires may occur when lint builds up in the filter or in the exhaust duct. Under certain conditions, when lint blocks the flow of air, excessive heat build-up may cause a fire in some dryers. To prevent fires:
Clean the lint filter regularly and make sure the dryer is operating properly. Clean the filter after each load of clothes. While the dryer is operating, check the outside exhaust to make sure exhaust air is escaping normally, If it is not, look inside both ends of the duct and remove any lint. If there are signs that the dryer is hotter than normal, this may be a sign that the dryer's temperature control thermostat needs servicing.
Check the exhaust duct more often if you have a plastic, flexible duct. This type of duct is more apt to trap lint than ducting without ridges.
Closely follow manufacturers' instructions for new installations. Most manufacturers that get their clothes dryers approved by Underwriters Laboratories specify the use of metal exhaust duct. If metal duct is not available at the retailer where the dryer was purchased, check other locations, such as hardware or builder supply stores. If you are having the dryer installed, insist upon metal duct unless the installer has verified that the manufacturer permits the use of plastic duct.