Each summer, vigilance is on hydration, light clothes or limitation of outings at the hottest hours. However, an unsuspected danger is hiding in your vehicle: a simple bottle of transparent water, left in full sun, can cause a fire.
The phenomenon is explained by a simple physical principle. The water contained in a bottle acts like a magnifying lens. When exposed to a certain angle to the sun’s rays, the light is concentrated on a specific point, exactly as when a child uses a magnifying glass to ignite a sheet of paper. The heat thus produced can exceed 400 ° C and trigger a start of fire in a seat, upholstery or an exposed console.
A real case in the United States
In 2017, an American employee noted smoke escaping from the console of his truck. At the origin of the incident: a simple bottle of water left in the cup holder, in full sun, which began to burn the seat. The rapid intervention of its owner avoided the complete destruction of the vehicle, but the plastic and the foam had already been charred in two specific points, testifying to the power of the phenomenon.
Extreme temperatures in a few seconds
To educate the general public, firefighters reproduced the experience. The measurements made confirmed that the radius of light concentrated by the bottle can ignite a paper in a few seconds. This intensity is sufficient to irreparably damage a seat or a dashboard, particularly in a vehicle parked in full sun during the heat wave.
How to avoid risk?
As a precaution, it is strongly recommended not to leave bottles of transparent water in your cabin, especially on the seats or in the cup holders exposed to the sun. Store them in the glove box, the trunk or, better still, favor reusable opaque stainless steel or isothermal bottles, which block light while resisting high temperatures.
In addition to the risk of fire, keeping a plastic bottle in a car exposed to heat also promotes the migration of chemicals to water, an additional danger in the event of hot weather. As a precaution, it is therefore preferable not to drink water that has remained in a vehicle in the middle of summer.
To summarize
A simple bottle of water left in a car can cause a fire by concentrating the sun’s rays like a magnifying glass. This little -known risk can reach 400 ° C. Avoid leaving your plastic bottles in full sun in your vehicle this summer.
