U.S. Consumer Product Safety Commission
subjected to carbon monoxide poisoning from improper dryer vent setups
In some cases faulty appliances are to blame,
but many fires can be prevented with proper dryer venting
Dryer exhaust fires now surpass creosote (chimney) fires in frequency
on a national level.According to the CPSC (Consumer Product Safety Commission)
, in most cases the
culprit is lint getting into the machine’s heating element and sparking
and fueling a fire. In response to this growing trend, many dryer
manufacturers now employ a device that shuts the appliance down when
airflow is obstructed. However, these safeguards are subject to wear
and have been known to fail. Not surprisingly, some fire departments
and insurance companies now require that dryer vents be inspected and
cleaned regularly.
With gas dryers, there is also concern of carbon monoxide (CO)
poisoning. Since lint and flue gases use the same exhaust
from the house, a blocked vent can cause CO fumes to back up into
the house. These fumes are colorless and odorless and they can be
fatal. Low-level CO poisoning mimics flu symptoms (without the fever):
headache, weakness, nausea, disorientation and deep fatigue. At higher
levels, occupants can fall asleep, lapse into a coma and die.
Dryer fires usually start beneath the dryer when the motor overheats.
Overheating is caused by a build-up of lint in the duct that increases
the drying time and blocks the flow of air, just like cholesterol in your
arteries can build up and block the flow of blood to your heart.
Naturally, any lint that has collected under the dryer will burn and the draft from the dryer will pull that fire up into the duct. Since the duct is coated or even blocked with lint, many times a house fire results. Other contributing conditions may include failure of the thermostat and limit
switches in the dryer, lint inside the dryer, a missing or damaged lint
screen, a crushed hose behind the dryer, or a bird’s nest or other debris
blocking the exhaust.
* Flexible plastic duct is no longer code-approved for clothes dryers. It is normally one of the first things burning lint will ignite, having been shown to flame in as little as 12 seconds. Lower cost and high flexibility often
make it attractive to unadvised homeowners installing their own machines.
* Flexible duct made of thin foil is not recommended for clothes dryers. It’s
tendency to "kink" and stop airflow makes it dangerous to use.
