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A Not-So Tempered Response

I just watched another story by a TV reporter about glass. This time, the topic was tempered glass breakage. I give the reporter an A for effort, but it’s a tough concept to understand quickly and completely. It seems in this case, the tempered glass in question was in a car sunroof, but it could just as easily have been in a building or on a table. At the conclusion of the report, any rational person would ask why car makers use tempered glass in sunroofs. Heck, they might ask why we use tempered glass at all.

Broken Glass2It was another attempt to give tempered glass a bad name and yet, I’ve decided the blame for all this is ours. That’s right. It’s on our industry. We have done very little to explain the inherent differences among different types of glass, nor have we offered the advantages and disadvantages of each. I’m tired of tempered getting such a bad rap because no one has set the proper expectations for it.

The expert in this report appeared to be the manager of a local glass warehouse. It would be nice to have some manufacturing and technical experts in the report, but that will most likely never happen. Almost everyone is afraid that their words will come back to haunt them—online, in a court case or some other dark place. That’s a shame.

I think if we explained it, people would understand. Here’s how I’d do it:

“Thank you for your inquiry about tempered glass. There are a myriad of different glass types on the market, each with their own characteristics, advantages and disadvantages. Figuring out which type of glass to use in which application is always an evaluation of major and minor factors.

“Tempered glass is a good product. It is a safety glass that breaks at higher levels of pressure than most glass does. Tempered glass sometimes, though not often, contains nickel sulfide stones. It doesn’t mean the glass has been manufactured incorrectly, it just sometimes occurs naturally as part of the manufacturing process. Those stones, on even rarer occasions, can cause spontaneous breakage.

“Use of laminated glass instead of tempered is a viable alternative in many applications, because laminated tends to hold together upon breakage. But tempered glass can resist very high pressure before it finally does break. And tempered glass is usually more resistant to problems that can be caused by solar heat gain, which is very important in a sunroof. All this taken together is why tempered glass is often used there. I hope this helps you understand why tempered glass sometimes seems to break ‘out of the blue.’”

No one questions when a balloon breaks. It’s just something we know and understand about balloons. No one is to blame, it’s just intrinsic in their nature. And while I am not suggesting that tempered glass is as fragile as a balloon, I am suggesting that we, as an industry, do a better job of explaining the different types of glass and what they can and cannot do. One man’s education is another man’s expose, and if we don’t set our own expectation levels, they will surely be set for us by those less knowledgeable.