A friend of mine from high school was baking something in Pyrex glassware. It exploded in her oven. I own tons of Pyrex, a very expensive Dacor double oven, and have a 3-year-old that likes to peek in the oven window to see what’s going on. So, naturally, I started to investigate. Turns out, this Pyrex exploding phenomenon is fairly common.
I read a story about a gal who opened her oven at the exact same time her Pyrex casserole dish exploded. The shards lacerated her face, but miraculously she closed her eyes just in time.
I read a story about someone who opened her oven after her pan had exploded. Hot glass flew out and burned the carpet nearby.
Another guy had it happen while washing his Pyrex in a sink full of water. He felt a burning sensation in his finger, took it out of the water and had a ¾ inch piece of glass lodged in his finger.
Some people claim that the reason this is happening is because Pyrex changed the formulation of the glass from borosilicate to soda lime. World Kitchen, the company who currently owns Pyrex, argues that this change shouldn’t matter and that soda lime is stronger.
But some believe that the older Pyrex, which I’ve always preferred due to it’s more square edges, is safer. I’m not a scientist so I can’t vouch for either claim. To me, the composition is irrelevant, because whatever it’s made out of can shatter into hundreds of pieces without warning.
This is when you take something from a cold environment to a hot one. It is acknowledged that Pyrex can explode when this happens. Even the people at trusty people at Cooks Illustrated have written about their experiences with exploding Pyrex in their test kitchens. I make-ahead meals like enchiladas and lasagna, freeze them and then bake at a future date (I use Cooks Illustrated’s The Best Make-Ahead Recipe). I used to do this primarily in Pyrex glassware.
Have you actually read the instructions that come with your Pyrex dishes? Odds are you ripped off the paper wrapper thinking, it’s glass and a no-brainer. There’s a long list of things you should and shouldn’t do with your Pyrex. Well, check this out (see link above for full instructions):
Mine is scratched and I bet yours is to some degree too. What I might think of as a minor scratch, someone else might consider “severe.” How would anyone be able to test my pan after it explodes into hundreds of pieces? The other thing I’ve never done with regularity is add water to cover the bottom of the dish when cooking foods that might release liquid.
Decide if you’re diligent enough to manage your Pyrex and other glassware. You should inspect it each time you bake. I’m a busy mom and am not confident I will do this. I’m not trying to be alarmist, but I’m swapping my Pyrex out for ceramic or metal ovenware. To me, it’s just not worth the risk for the relatively minimal cost it will take to switch to new pans.
The people in the stories I refer to all claim that thermal shock was not involved, and that their explosions were totally out of the blue. This is what concerns me. It’s possible they had Pyrex glassware in perfect condition that exploded.
Pyrex has addressed the situation on their website in a section called Truth About Pyrex Glass. You may read stories about Pyrex glassware exploding on Chowhound or Consumer Affairs (where two of my stories above are from). There are also articles online calling this a hoax, which given that it just happened to a very well educated friend of mine, I don’t believe.
Photo credit: Flickr/technodad