Is It Safe to Sleep in a Car Without Starting the Engine?

[EllieMarie]

It is not safe to sleep in a car without starting the engine. Here are the reasons: 1. Air Quality: With the windows closed, air circulation is restricted, leading to an increase in carbon monoxide concentration, which can be fatal. In a closed environment, fresh oxygen cannot enter the car, and the air conditioning's internal circulation may introduce carbon monoxide. Carbon monoxide is colorless and odorless; small amounts may not be harmful, but as its concentration rises, it can cause oxygen deprivation and death. 2. Internal Circulation: Continuously using the internal air circulation mode reduces air freshness and increases pollutant levels. Prolonged use of internal circulation deteriorates the air quality inside the car.