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Fuel-Burning Appliances:
Like portable heater, gas or wood burning
fireplace, gas kitchen range or cooktop, gas clothes dryer.
Damaged or Insufficient Venting:
Corroded or disconnected water heater vent pipe, leaking
chimney pipe or flue, or cracked heat exchanger, blocked or clogged chimney opening.
Improper Use of Appliance/Device: Operating a barbecue grill or vehicle
in an enclosed area (like a garage or screened porch).
Transient CO Problems:
“Transient” or on-again-off-again CO problems can be caused by outdoor conditions
and other special circumstances. The following conditions can result in transient CO situations:
1.
Excessive spillage or reverse venting of fuel appliances caused by outdoor conditions such as:
•
Wind direction and/or velocity, including high, gusty winds. Heavy air in the
vent pipes (cold/humid air with extended periods between cycles).
•
Negative pressure differential resulting from the use of exhaust fans.
•
Several appliances running at the same time competing for limited fresh air.
•
Vent pipe connections vibrating loose from clothes dryers, furnaces, or water heaters.
•
Obstructions in or unconventional vent pipe designs which can amplify the above situations.
2.
Extended operation of unvented fuel burning devices (range, oven, fireplace).
3.
Temperature inversions, which can trap exhaust close to the ground.
4.
Car idling in an open or closed attached garage, or near a home.
These conditions are dangerous because they can trap exhaust in your home. Since these conditions can
come and go, they are also hard to recreate during a CO investigation.
Potential Sources of CO in the Home
