PSA: last night one of our pyrex cooking dishes exploded.

not fractured, exploded. “pyrex isn’t supposed to do that” we thought.

as of a few years ago, Pyrex sold their brand, the new company changed glass recipe as a cost cutting measure, resulting in a pandemic of exploding cookware and a class action lawsuit.

thankfully the patent has expired and the keyword to look for in competing glass cookware products is “borosilicate glass”

@zensaiyuki i didn't know they sold the brand. not surprised, thank you.

@zensaiyuki about 6-8 years ago, I slept over at a friend's house for his birthday and they cooked a macaroni and cheese casserole and the Pyrex baking dish it was in just spontaneously shattered while cooling, making a mess and ruining a large amount of food in the process

Fwiw, as of when I looked into it, Pyrex labware is still made of the good glass, it's just the bakeware that's bad now

@zensaiyuki I had that happen about ten years ago! It was terrifying!

@zensaiyuki i remember reading this is only a thing in the US and european pyrex has always been borosilicate? Might be worth a double check

...i sure hope the laboratory glassware is still borosilicate. That could cause some *major* problems if they started using soda-lime glass instead

@Felthry in Australia. our pyrex exploding seemed pretty real. someone else replied here that lab pyrex is still borosilicate.

@zensaiyuki @Felthry welcome to capitalism…


if Australia is participating in the European Song Contest, how hard would it be to also get the consumer protection wer have here?

i hate Britain is leaving… wanna join?

@meena @Felthry that would be great but unfortunately i don’t think the current government would go for it.

@Felthry @zensaiyuki a good way to tell is what case the label is in, PYREX(r) is the trademark for the borosilicate formula, and pyrex(r) is the newer soda-lime

the new formula SHOULD be safe as long as it isn't moved between hot/cold environments without a room temperature period in the middle, but the all-caps PYREX ones are the much safer borosilicate glass

i believe? the older formula also looks a little more yellow, but i can't verify

@Kat @Felthry @zensaiyuki iirc pyrex labware is still the good stuff and imho using lab glassware for cooking would be cool as heck

@Kat @Felthry @zensaiyuki this actually seems like a reasonable price for as assortment of high-quality glassware

unfortunately most stuff other than these assortment packs are sold by the case

@Galuade it's missing the best one though, the 5mL beaker

never actually used one of those but there was always at least one sitting out in our high school chemistry lab and it was the Best Thing

@starseeker @Galuade it is but i can't find any pictures of one that give you a good sense of size

did find a 5 mL erlenmeyer flask though

also several 1 mL volumetric flasks, which have a special base just so they don't fall over because otherwise they're too tiny

Minor caps 

re: Minor caps 

re: Minor caps 

@Kat @Felthry what was dangerous was we believed because it was pyrex that it could handle temperature changes safely, because it’s goddamn pyrex, which apparently doesn’t mean much anymore.

@Kat @Felthry i didn’t know about the case distinction. seems like a silly thing to expect people to just know to avoid a face full of hot glass.

@zensaiyuki @Kat @Felthry Ah, I ever thought it couldn't, that it could support hot temperatures but not the thermic impact. Wow.

@Kat @Felthry @zensaiyuki I've noticed older PYREX has a slight tinge of off-wihte, but I'm not sure if that's glass formula related or simply age related

@zensaiyuki Ugh, because of course it was all about cutting costs 😒 it's always some rich jerk trying to save money.

I'm curious – do you know what kind of glass the shattering Pyrex things are made from?

Ohhh tempered soda lime glass! That explains the explosion. Geez, why couldn't they just stick to borosilicate like any sensible person?

@InvaderXan it would be fine if we knew what it was beforehand. “pyrex” kinda sets expectations. it’d be like buying oreos, opening the package and finding vanilla wafers. nothing wrong with them but it’s not what i bought! except with a hot exploding glass twist.

@zensaiyuki Right?? Damn, I didn't realise I needed to actually check what kind of glass I was buying these days. That's annoying.

@zensaiyuki hmm, I guess that explains why I've seen them sold quite a bit cheaper than they used to be...
Our oven dish hasn't exploded yet fortunately, but thanks for the warning!

@zensaiyuki I actually had to explain this to one of my science teachers once, that was a cursed as hell day.

@zensaiyuki I think they were thinking of the lab stuff, which iirc is still fine? but to say "oh, yeah, pyrex is perfectly fine in heat" isn't a good thing to say to an entire class with no qualifiers

@zensaiyuki correct, see this happen a lot now and people don't realize it.

Only buy the old Pyrex at estate sales

@zensaiyuki I had a measuring jug explode a while ago! At room temperature, standing on a room-temperature stone countertop, so it can't have been temp differentials. Fortunately it was empty so I only had to clean up glass, not glass and some possibly sticky or greasy liquid.

@zensaiyuki Arcuisine, but made of the same type of glass.

@zensaiyuki Exploded?! That's pretty fucking serious.
Is there any literature/studies on this?

@ferds just search “exploding pyrex”, there’s tonnes of stuff. someone pointed out to me earlier that PYREX all caps is a different glass and brand from “pyrex” lowercase. the background is on wikipedia.


Old pyrex could explode too, if you did terrible things to it. I had one go in the late 80s.

To be fair, my roommate had turned on the wrong burner on the hob, heated the pyrex to a temperature I like to describe as 'really hot' and then dumped cold tomato sauce on it.

Hot pyrex shards burned marks into my linoleum floor. It's a bloody miracle no one was hurt.

@zensaiyuki I also learned this fact the hard way. It was about 7 years ago. I was being a dumbass and left an empty pyrex pan on an active electric stove burner.

Luckily, when the thing exploded into tiny pieces, I was on the other side of my studio apartment. No one was hurt, and no real damage was inflicted.

The Pyrex pan chose a fitting time to explode. I was watching Zombieland, and a shooting scene had just started.

@zensaiyuki oof, yeah, the soda-lime glass problem. Sorry that happened. I hope cleanup wasn't too much trouble.

@gnomon i wish I knew how to clean up glass in a way that doesn’t leave 1000 tiny invisible foot lacerating shards

@zensaiyuki @vfrmedia note that this does not apply to the labware line of Pyrex, which remains high-quality borosilicate

And also that not all things marked "borosilicate glass" are fully heat safe. Make sure what you get is actually advertising itself as heat safe too.

Not gonna lie, misread that as "glass action lawsuit"

@RussSharek @zensaiyuki Glass cookware collector here. Corning sold off their housewares division 20+ years ago but even back then most of their ovenware was not borosilicate. They claim it's because borosilicate is more likely to break if dropped. If you want to use something on the stove top you're looking for Corning Vision, which you can often find for cheap in thrift shops in the US, or is still made new in France.

@zensaiyuki "as of a few years ago" - 1998, to be exact.

If you're looking for Pyrex that won't explode (or at least is far less likely to), check the logo. If it's all caps e.g. "PYREX", then this is the version of the trademark which covers borosilicate glass. The lowercase version of the trademark e.g. "pyrex" is the one used on soda-lime products.

@TerrorBite unclear which year this started happening in Australia. check out all the other replies in this thread.

Sign in to participate in the conversation

Server run by the main developers of the project 🐘 It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!