Is It Safe to Sleep in a Parked Car with the Engine Off?

[LaWalter]

It is not advisable to sleep in a car, especially for extended periods, due to the risk of oxygen deprivation and suffocation. Here is additional information about sleeping in a car: 1. Generally, sleeping in a car with the engine off is not a problem, provided it is parked in an open and well-ventilated area. It is best to leave a window slightly open to ensure adequate air circulation. 2. Sleeping in a car with the air conditioning on and windows closed is extremely dangerous. 3. If the engine remains idling for a prolonged period, incomplete fuel combustion may occur, producing carbon monoxide gas. Inhaling excessive amounts of carbon monoxide can lead to poisoning.

[StJulia]

Sleeping in the car after turning off the engine is theoretically feasible, but safety risks must be cautioned. When asleep in the car with the engine off, lack of air circulation can lead to carbon dioxide buildup, potentially causing suffocation or physical discomfort. I’ve personally taken short naps during long drives and recommend choosing safe parking spots like service areas, cracking a window slightly to allow fresh air in, which helps mitigate issues. The confined space of the car makes prolonged sleep uncomfortable due to awkward postures, often resulting in back pain upon waking. Temperature fluctuations are also significant—keeping a light blanket handy is advisable for hot or cold weather. Sleeping with the engine running is more hazardous due to the risk of carbon monoxide poisoning; this risk decreases when the engine is off. Parking location matters too—avoid remote or dimly lit areas to prevent disturbances from strangers. While suitable for brief rests, it shouldn’t become a regular habit, as it’s detrimental to both health and alertness.

[VonLogan]

During long trips, I occasionally take short naps in the car, and turning off the engine is a basic practice. This method saves money and fuel, and is much safer than leaving the engine running, as a running engine can allow exhaust fumes to seep into the car, potentially causing poisoning. Find a safe and quiet spot to park, such as a shopping mall parking lot, lock the doors, and crack open a window for ventilation. The airflow helps you sleep more comfortably. However, the narrow space makes it uncomfortable—sleeping with legs curled up for too long can cause numbness, so bringing a small pillow can help. Weather plays a big role—summer heat and winter cold can be challenging since the AC doesn’t work with the engine off, so you have to rely on natural airflow. I also keep an eye on the battery; a short nap won’t drain much power, but prolonged sleep might make it hard to start the car. Overall, it’s a practical emergency solution during travels, but don’t overlook the potential risks.

[VonReed]

I think sleeping in the car after turning off the engine can be tried briefly, but be cautious about air quality. The enclosed space can lead to oxygen deprivation and headaches, so opening windows for ventilation when the engine is off is crucial. Remember to park in rest areas or familiar places to ensure no one disturbs you. Uncomfortable body posture can cause neck or back pain after waking up, which is especially unhealthy for children. Doing this long-term isn't good for health—it's better to find a hotel to rest. When I'm tired on the road, I take short naps but set an alarm to control the duration. The risks are greater with the engine running; at least turning it off avoids exhaust poisoning. Safety first—handle with caution.