A clogged, damaged, or disconnected dryer vent presents various hazards,
and each issue can result in one or more of the threats described below.
A stubborn dryer vent clog poses signiﬁcant risks that can lead to severe
but avoidable consequences.
Lint Fire. Dryer lint fires originate in the dryer cabinet or dryer vent system from
excessively high temperatures. The problem stems from a restricted dryer vent pathway
due to a damaged or improperly installed dryer vent system, excessive lint, water, or both.
The dryer lint screen only captures approximately 25% of lint; the remainder passes through
the vent system or makes its way inside the dryer cabinet. Fires in dryer exhaust ducts
pose a severe threat to consumers and illustrate the importance of annual dryer vent inspections and preventative maintenance.
Carbon Monoxide Poisoning. Carbon monoxide will enter the home if the
gas-fired dryer exhaust vent should become partially or entirely blocked, damaged, or
disconnected. A resistance in positive airflow, due to a clog, will create back pressure and
allow poisonous gases to enter the living space. A damaged or disconnected duct can leak
CO2 anywhere along its pathway. A clean and integral exhaust system, without voids, allows
the discharge of heat, moisture, and combustion by-products. The potential for gas leakage
in the laundry room or along the vents path is another reason to install carbon monoxide
detectors throughout the home.
Mold Exposure. When a load of clothes is drying, heated water travels through
the vent system as a gas. If a clog or disconnect occurs, water will cool to a liquid and either
saturate building material in the ceilings, floors, and walls or stays trapped in the vent.
The wet material becomes a perfect breeding ground for mold spores to grow and may
cause health problems for the home’s occupants.
Respiratory Illness. Birds, squirrels, and insects can make their homes in your
dryer exhaust system. These creatures are not only a nuisance but also a potential health
hazard to homeowners. One common risk associated with bird fecal matter is
Histoplasmosis, a type of lung infection caused by breathing in dust from soil enriched
bird dung. If these critters find their way into your dryer exhaust system, be aware of the
dangers and hardship they can cause.
Poor Air Quality. It is crucial to ensure that the room where the dryer resides has adequate make-up air. If a dryer is in a closet, no other fuel-burning appliance may co-exist. Suppose a dryer operates simultaneously with a gas furnace; it will pull smoke, fumes, or cool air from the furnace vent into the room to make up for the deficiency. If this occurs, be aware of the danger of indoor air pollution, carbon monoxide exposure, and appliance inefficiency. We recommend installing a carbon monoxide detector in your laundry room for this reason.