According to the U.S. Consumer Product Safety Commission, there are over 14,000 fires, 10 deaths and 10 injuries annually due to clothes dryer fires, and several hundred people a year are also subjected to carbon monoxide poisoning from improper dryer vent setups. Although faulty appliances are to blame in some cases, many fires can be prevented with proper dryer venting and cleaning.
So…just how does a Clothes Dryer Fire Occur?
Lint accumulation and reduced airflow feed on each other to provide conditions ripe for a fire. Lint is a highly combustible material, which, interestingly enough, is one of the ingredients in a recipe for Boy Scout campfire starters. Lint sheds from all clothing during the drying process, and a lint trap if cleaned and in place will often collect most of that. In older homes, straight ductwork would take the remainder out of the basement and the house through an exhaust hole.
Most older homes have basement laundry areas, nowadays though many newer homes tend to have dryers located away from an outside wall in bedrooms, bathrooms, kitchens and hall closets. These new locations mean dryers tend to be vented longer distances and vents are generally installed with sharp turns and bends to accommodate the structure of the home. As a result, dryer vents are harder to reach, and also create more places for lint to gather. The ideal solution is to have short, straight, dryer duct venting. However, a dryer vent booster, while not the ideal approach, can improve your dryer venting in cases where your venting is longer and/or has more bends than it should. In addition to creating a fire hazard, if the venting is too long and/or has two many bends, it will cause your dryer to take much longer than necessary to dry loads. The venting material tends to be flexible material which, although ideal for construction in homes, may offer additional places for lint to collect on it’s way out of your house.
What’s happening inside my Dryer?
Lint is! As you know from cleaning out your lint filter, dryers produce very large quantities of lint. Although you may assume that lint traps catch all the lint, and that all you need to do is clean them out after each load, a significant amount of this lint is not caught by the lint trap and builds up inside the dryer-including on the heating element, causing it to overheat and possibly catch fire. As a rule, a fire starts from a spark in the machine. However, improper clothes dryer venting practices outside the dryer can play a role in this process.
What about outside my Dryer?
There are many improper dryer vent practices which restrict airflow and lead to lint buildup, some preventable causes of clothes dryer fires are:
1. Dryer vents which are too long, have too many bends, or don’t use a dryer duct booster, which results in lint buildup. If there’s any say in the matter with your house, remember the adage that shorter and straighter is better. The air pushing the lint out that gets through your lint screen is powerful enough in short runs to push it out of your house, and make cleaning it a snap.
2. Use of flammable, flimsy plastic or foil duct extenders. Only metal vents should be used, which is what most manufacturers specify. Metal vents also resist crushing better than plastic and foil, which allows the air and lint to be carried out of the system. Reduced airflow from build-up or crushing can cause overheating and wear out the appliance faster. In fact, many state and local municipalities have placed requirements on new and remodeling projects to include all metal dryer venting. If you aren’t sure what’s required, or was when your house was built, call and ask the Building Department! They’ll let you know what works best and safest in your house!
3. Inadequate clearance space between dryer and wall. Many people create problems by putting their dryer right against the wall, crushing the venting material in the process. The cumulative effect of reduced airflow and the resulting lint build-up prevent the dryer from drying at the normal rate. This causes the high temperature limit safety switch to cycle on and off to control the heater. Most high temperature limit safety switches were not designed to continuously cycle on and off, so they fail over a period of time. Our districts two most recent dryer related fires were due to excessive lint build up due to the crushing exhaust pipe! It can happen!
4. Failure to clean the dryer duct. Keeping your dryer clean not only reduces the fire hazard, you also save money since your dryer will run more efficiently and last longer. To keep your dryer clean, use a lint brush or vacuum attachment to remove accumulated lint from under the lint trap and other accessible places on a periodic basis. Then, every 1-3 years, depending upon usage, have the dryer taken apart and thoroughly cleaned out by a qualified service technician. Most importantly though, clean the lint trap after each use.
Is there a way to tell if my dryer might be clogged?
Prevention is the tried and true way of making sure you never have a problem. If the clothes take a longer period of time to dry than they should, come out hotter than usual or if the vent hood flapper doesn’t open you may need to have maintenance done on your dryer.
Remember: Checking and cleaning your lint traps and occasionally cleaning your dryer exhaust pipes goes a long way towards dryer clothes and safer houses!