During extremely hot weather, many people choose to sit inside their cars, turn on the air conditioner, and rest for a while to escape the heat. But what seems harmless may actually become life-threatening under certain conditions.

A tragic incident recently shocked many people after a woman in her 30s was reportedly found unconscious inside her parked car while the air conditioner and engine were still running.

The case quickly sparked debate online, with many asking:

“Is it actually dangerous to sleep inside a car with the AC on?”

Woman Found Unresponsive Inside Parked Car

According to reports, the incident happened in Shenzhen, China, around 4 PM when road staff noticed a car parked in the same location for an unusually long time.

When they approached the vehicle, they reportedly found a woman sitting motionless in the driver’s seat with no visible signs of breathing.

Emergency responders were immediately called, and rescuers had to break the car window to remove her from the vehicle. Despite medical efforts lasting more than 30 minutes, she could not be revived.

Authorities reportedly found:

• no major external injuries,
• the doors tightly closed,
• and the air conditioning system still operating.

Doctors Suspect Carbon Monoxide Poisoning

Respiratory specialists explained that the incident may have involved:

carbon monoxide poisoning.

Experts warn that when a vehicle remains idling for long periods — especially in:

• poorly ventilated areas,
• enclosed parking structures,
• or low-airflow environments,

exhaust gases may slowly accumulate around the vehicle.

Carbon monoxide is especially dangerous because it is:

• colorless,
• odorless,
• and nearly impossible to detect without equipment.

Doctors say early symptoms may include:

• dizziness,
• headache,
• weakness,
• breathing difficulty,
• and confusion.

However, if someone is asleep, they may lose consciousness before realizing anything is wrong.

In severe situations, experts say dangerous exposure can develop surprisingly quickly.

Doctors Warn About These 5 Risky AC Habits

1. Turning The AC On Full Blast Immediately After Entering A Hot Car

After sitting under the sun, vehicle temperatures can become extremely high. Experts recommend:

• opening windows first,
• allowing hot air to escape,
• then gradually cooling the car.

2. Pointing AC Vents Downward Constantly

Because cold air naturally sinks, directing vents upward may help distribute cool air more evenly throughout the vehicle.

3. Keeping Air Recirculation Mode On Continuously

While recirculation cools the car faster, experts say using it too long may reduce fresh airflow inside the cabin.

Drivers are advised to occasionally switch to outside air mode.

4. Not Using The AC System For Months

Leaving the AC unused for long periods may allow:

• mold,
• bacteria,
• and moisture buildup

inside ventilation systems.

5. Ignoring AC Cleaning And Air Filter Maintenance

Dirty filters and contaminated ventilation systems may negatively affect:

• breathing,
• allergies,
• and long-term respiratory health.

Experts Say Resting In Cars Is Not Always Dangerous — But Carelessness Can Be

Specialists emphasize that simply sitting in a car with the AC on does not automatically become deadly. However, risks increase significantly when:

• engines idle too long,
• ventilation is poor,
• or people fall asleep inside tightly sealed vehicles.

Doctors continue warning drivers not to underestimate how quickly dangerous situations can develop inside parked cars — especially during extreme heat.