Common sources of dangerous carbon monoxide include kerosene and gas space heaters without proper venting, leaking chimneys and furnaces, back-drafting from furnaces, gas water heaters, wood and gas stoves, and fireplaces and motor vehicle exhaust. Although occupants may not be present during the hours when carbon monoxide concentrations are high, any potential problem must be investigated and the source be determined, removed or repaired.

JMK highly recommends that a trained professional inspect and repair any heating system demonstrating a problem and to ensure that gas stoves are properly ventilated. If a ventilation system is located near idling delivery vehicles, the vents should be redirected or the vehicles relocated to prevent carbon monoxide pollution. It is also important that heating, air-conditioning, and ventilation systems are not on the premises so as to prevent the prevent the migration of odors. The HVAC unit may be located near the fresh-air intakes provided it is a sufficient distance from bathroom and kitchen exhaust vents. This will prevent capture and re-circulation.