Three years ago, Consumerist told you about the possible shattering risk of so-called “oven-safe” Pyrex bakeware. And for the last year, our investigative siblings at Consumer Reports have been combing through complaints to the Consumer Product Safety Commission and testing Pyrex and other glass bakeware in the CR testing facility.

For its article in the current issue of Consumer Reports, the magazine investigated 163 incidents of glass bakeware that shattered suddenly:

In some cases it was in the oven, while cooling on a countertop or even while they were holding it, sometimes sending shards of hot glass flying and causing injuries. Only some of the cases seemed to involve clear violations of the bakeware’s instructions. While hundreds of millions of glass dishes are used safely each year, we saw enough incidents to raise concern.

In the CR labs, the magazine tested not only Pyrex and Anchor Hocking brand glass bakeware sold in the U.S., but also European-made Pyrex and Arcuisine Elegance glass bakeware. As we reported back in 2007, Pyrex sold in the U.S. is now made of soda lime glass instead of the borosilicate that had been used for decades and which is still used in Europe. They even managed to scrounge up some old borosilicate Pyrex made in the U.S. for comparison.

In the video below, you’ll see that when the soda lime bakeware is exposed to extreme heat and then placed on a wet granite counter, it shatters instantly. The borosilicate bakeware from Europe fared better, though it still shattered after being heated in ovens at 500 degrees. However, the older borosilicate Pyrex didn’t even shatter at that temperature.

As a result of its investigation, Consumer Reports has called on the CPSC to look into the problem of shattering bakeware. And when you buy glass bakeware, be careful to read over the manufacturer’s instructions for handling the product.

FOIA requests examine glass bakeware that shatters [Consumer Reports]

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