What caused the glass door to explode?

One is the quality of glass, that is, in the production process of self-contained glass, a small amount of impurities (mainly nickel sulfide particles) are mixed in the raw materials. Under the action of temperature change, impurities expand, and stress is generated in the glass, which leads to self-explosion. Second, improper use of glass is the weakness of tempered glass. In the process of use, if you touch the corners of tempered glass, it is easy to cause the glass to burst.