Sleeping in a parked car with the air conditioning (AC) running may seem harmless, especially during hot weather or when travelling long distances. However, the practice can expose occupants to carbon monoxide poisoning, a potentially fatal condition.
Carbon monoxide is a poisonous gas produced when fuel burns. In vehicles, it is released through the exhaust system when the engine is running.
Although the gas is colorless and odorless, it can enter a vehicle’s cabin if the exhaust system is faulty or fumes find their way inside through openings. The risk is particularly high when a vehicle is parked in an enclosed or poorly ventilated space, where exhaust fumes can accumulate.
Once inhaled, carbon monoxide reduces the blood’s ability to transport oxygen to vital organs, including the brain and heart.
Early symptoms of carbon monoxide poisoning include headaches, dizziness, nausea, vomiting, and confusion. Prolonged exposure can cause unconsciousness, brain damage, and death.
The danger is particularly concerning when someone is asleep because they may not recognize the symptoms or wake up before the poisoning becomes severe.
It is important to understand that the air conditioner itself does not produce carbon monoxide. The danger comes from the vehicle’s running engine and exhaust fumes.
While the risk varies depending on the vehicle’s mechanical condition and parking environment, sleeping in a stationary vehicle with its engine running is not a safe practice.
Motorists are advised to switch off their engines before sleeping and avoid running vehicles in enclosed spaces such as garages. Anyone who suspects carbon monoxide exposure should immediately move into fresh air and seek emergency medical attention.
Carbon monoxide poisoning is preventable, but its lack of color and smell makes it particularly dangerous. A seemingly comfortable rest inside a parked vehicle could have fatal consequences.
