Can car glass shatter automatically?
3 Answers
Car glass self-explosion is a complex phenomenon with no unified conclusion, but in most cases it is caused by temperature. Rapid temperature changes leading to uneven thermal expansion and contraction can cause the glass to shatter. Just like an egg, if the force is evenly distributed at every point, even a large force won't crush it. However, if the force varies at any point beyond the safety limit, it will break. Sudden cooling or heating can cause this self-explosion phenomenon. There are three main reasons for car glass self-explosion: 1. Poor tempering treatment of the glass itself. 2. Uneven heating during glass film application. 3. Excessive thermal variation in the glass film.
It is indeed possible for car windows to shatter automatically. Having driven for over twenty years, I've witnessed this several times. The most common scenario is when the glass, after being exposed to intense summer heat, is suddenly washed with cold water, causing it to crack due to the extreme temperature difference between the inside and outside. Additionally, impurities or particles trapped inside the glass during manufacturing can suddenly cause it to shatter during use. There was also an instance where a neighbor's car developed a hidden crack after being hit by a small stone on the highway, and the window completely shattered two weeks later. Fortunately, modern cars are equipped with laminated glass, which doesn't break into sharp pieces even when cracked. If you encounter such a situation, never touch the broken glass with your hands. It's best to temporarily secure it with tape and drive to a repair shop.
My car had its windshield replaced just last year. At the time, the mechanic mentioned that spontaneous glass breakage isn't too uncommon. Tempered glass inherently carries a certain probability of spontaneous breakage, primarily caused by residual internal bubbles or impurities during manufacturing. Once during a long-distance drive, I encountered hail that cracked the windshield, and three weeks later, while parked roadside, it suddenly shattered entirely. Adding film during modifications is also a risk factor, as low-quality heat insulation films can create hot spot pressure differentials on the glass surface. When washing your car, avoid spraying cold water directly onto hot glass, especially right after parking in summer—don't rush to wash it.
