What makes pyrex explode

Other than being completely surprised and a little annoyed about having to clean tiny bits of glass out of my sink , I was unhurt, not even a scratch. For example, a calculation published by the American Ceramic Society found that borosilicate glass can withstand a sudden temperature change of up to about degrees Fahrenheit, whereas tempered glass can withstand a temperature change of about degrees.

The publication references the tests performed by Consumer Reports , which used dry sand heated in casserole dishes. However, since sand gets much hotter than food, some experts say these tests which are often cited in news stories about Pyrex are too extreme and are not an accurate representation of durability under normal use.

According to excerpts provided to us by Hugh Rushing, former executive vice president of the CMA, the CMA tests suggest that glass bakeware should be able to withstand being abraded with sandpaper to simulate wear over time , heated in the oven for 20 minutes, and then submerged in a water bath with a temperature difference of degrees Fahrenheit.

This procedure was developed in conjunction with a committee of glass manufacturers and industry consultants, and it has been tested on a variety of glass samples from all the major glass producers, with the results submitted to an independent lab for analysis. And though adhering to these standards is voluntary, Rushing told us that a majority of cookware retailers and manufacturers subscribe to them. It sounds obvious, but you can help extend the life of your glass bakeware and tableware by treating it with care.

You may be subjecting your tempered wares to extreme temperature changes and other abuses without even realizing it. Here are some tips for minimizing the risk of tempered-glass items spontaneously breaking:. You may be wondering: Why use tempered-glass bakeware at all? For baking, glass conducts heat gently and evenly and offers the advantage of allowing you to see whether the bottom of your food is fully cooked and browned.

Tempered-glass bakeware tends to be more affordable than ceramic or borosilicate, and we think Pyrex makes a number of simple, well-designed pieces, such as its classic pie plate or these oven-safe food storage containers. You could also buy Pyrex borosilicate bakeware made in France The European Pyrex is now a separate company not related to Corelle Brands.

Just keep in mind that even borosilicate glass can break from thermal shock, albeit into fewer, larger pieces. The original Pyrex cookware was made using a particular, thermally robust composition called borosilicate glass. Interestingly, the name Pyrex came from the accidental discovery that the composition, which was an attempt to improve the heat resistance of glass battery jars, could be used to cook food.

The story goes that one of the Corning lab scientists, Jesse Littleton, one day brought home the bottoms of a few of the borosilicate glass jars for his wife to use as pie tins.

The original name Py-Right was a phonetic nod to those home baked pies. In later years, Corning competitors, and finally Corning, itself, substituted a different glass composition-soda lime silicate glass-for the borosilicate Pyrex cookware. The other main competitor in this field is Anchor Hocking Glass Co. Both World Kitchen and Anchor Hocking now use the soda lime silicate glass instead of the original Pyrex borosilicate glass composition.

Bradt indicated that a 99 degree temperature change is enough to cause soda lime silicate to break; perhaps in instances like removing glassware from the oven to a room-temperature trivet. Borosilicate glass, the original material Pyrex was made out of, can withstand a degree temperature change. Corelle Brands vehemently denies it has put users at risk by changing the makeup of Pyrex. Yet many online users have documented their glassware shattering while cooking or brought out of baking conditions.

Complaints about Pyrex glassware can be found on Consumer Affairs, a website full of consumer mishaps with faulty products. There are over complaints about Pyrex and the overall satisfaction rate of the product receives a 1 out of 5. A recent complaint from Dec. Thanks for sharing. Oops, we messed up. Try again later. Why Pyrex Shatters: Pyrex is made of glass. What Now? Make a Donation Newsletters Give a Gift.