Water Bottles Left In Car Can Cause Fire: Here Is How

Water bottles as a cause of car fires

A water bottle can act as a lens to focus sunlight and heat and cause a fire

Most of the North Indian states are experiencing an extreme heatwave. The temperature during the day exceeds 40 degrees Celsius, and authorities have issued warnings for the heatwave. With the rise in temperature, we have also started seeing several incidents where vehicles, either running or parked outside, are catching fire. There are several reasons for such accidents, and one of them is the plastic water bottle that most of us carry in our cars. How does that become a reason for a fire in your car? Let’s find out.

With temperatures rising every day, people often carry water with them in the car. Some carry it in transparent plastic bottles while others buy chilled water bottles from shops. After drinking the water, most of us leave the water bottle in the car. The majority of cars in India are parked out in the sun, turning this simple-looking water bottle into a dangerous tool that can start a fire.

In many cases, we have seen the water bottle concentrating the rays from the sun and starting a fire or even destroying the interior of the car. In the video shared above, we can see the car owner advising people to throw away the plastic water bottles that they normally carry in their cars. If you really have to carry a water bottle, we request you to keep it or store it in a place where there is no direct sunlight.

What Does a Water Bottle Do?

Today I learned not to leave a clear bottle of water in my car on a hot sunny day!!
by inWellthatsucks

After drinking water, most of us carelessly leave the bottle in our car. There is often some water left in the bottle, and that is what makes things dangerous. The water stored in the plastic bottle actually starts acting like a magnifying glass. We all know what happens when a magnifying glass is held under direct sunlight.

The magnifying glass concentrates the sun rays, and it is so powerful that it can start a fire in just a matter of seconds. The same process happens here too. The sunlight, after passing through the water in the bottle, gets concentrated and falls on a particular portion inside the car cabin. In most cases, it is the seat covers. When the sun rays keep falling on a particular spot for some time, the portion starts smoking, and over the next few minutes, the smoke turns into a fire and destroys your vehicle.

Water Bottles Left In Car Can Cause Fire: Here Is How
Water Bottle starts fire

If you are one of those people who take water bottles with you in the car, never leave them in the car to be absolutely safe.

if you absolutely have to keep the bottle in the car, hide it away from direct sun (and don’t forget you have hidden it!). You can also use reusable metal flasks which keep drinks cool for a long time. Ensure that you keep these also away from direct sun.


Parking is a major problem for most of us in India. Only a limited number of car owners get a proper parking spot with a roof in India. Most of us have to leave our cars out in the open. This creates a problem, especially when you come back to get your vehicle. The extreme heat trapped inside the car often makes it difficult for the passengers to sit.

Water Bottles Left In Car Can Cause Fire: Here Is How

In such situations, it is always a good idea to roll down your windows a bit and blast the fan so that the hot air from the cabin can be pushed out. Alternatively, drive the car with the windows down for some time, and once the heat inside the cabin is low, you can start using the AC to cool down the cabin.

You can also leave the windows open by a tiny few millimeters so the hot air inside can escape. However, this might make it easier for thieves so do not do this if your car is not parked in a safe spot.