I’m attaching this interesting article I came across. Make sure that you don’t expose your Pyrex oven dishes to extreme temperature changes- remember that Pyrex is still glass no matter how good the quality.
A Problem With Pyrex? Experts We Consulted Say Yes
CHICAGO (CBS) ―
Close to 370 million pieces of Pyrex have been sold in the U.S. in the last 10 years, but CBS 2 has discovered consumer complaints of Pyrex ovenware breaking explosively.
While this is a rare occurrence, CBS 2 Investigator Pam Zekman reports on why some glass experts believe there’s a problem with Pyrex.
Several glass experts with doctoral degrees in material sciences examined samples of Pyrex glassware and fragments. They also reviewed some of the 300 consumer complaints about Pyrex exploding in kitchens — both inside and outside ovens. In some cases, glass went flying.
“It suggests to me that there is a real problem in the material itself,” said Dr. Stephen Freiman, Ph.D., a former Department of Commerce ceramics chief.
For example, in the Tuso family kitchen one piece flew 12 feet across the room, hitting Gina Tuso’s daughter, Julia Tuso. Her hand and neck were burned.
World Kitchen, the maker of Pyrex, says most incidents are the result of consumers failing to follow instructions on the Pyex label.
Nonetheless, the glass experts the 2 Investigators spoke to are concerned.
“These certainly are not fully tempered and have very little tempering at all,” said Richard Bradt, Ph.D.
If the glass were tempered to a greater degree, they say, it would be less likely to break as a result of temperature changes.
“It would be very much stronger or resistant to thermal stress,” Bradt added.
“Typically a fully tempered glass, very similar to the side windows on your car, if that broke, it dices into fine small pieces and the pieces have rounded corners so they won’t injure someone if they get hit,” said University of Florida Professor Jack Mecholsky, Ph.D.
Mecholsky has been hired as a consulting expert in a lawsuit against World Kitchen involving a product other than Pyrex. World Kitchen says this shows his views are biased. However his opinions are generally consistent with those of other experts the 2 Investigators consulted.
“This was breaking with relatively large pieces…very few small pieces and they were certainly not rounded. They were sharp edges,” Mecholsky said.
Terry Rhoads says when a Pyrex dish exploded while he was cooking, a sharp shard sliced into his foot and he could not move his toes.
“The tendon had been separated, cut in two basically,” Rhoads explained.
Professor Sheldon Mostovoy says Pyrex is safe, but the instructions are inadequate.
“The problem here is using a glass that is so sensitive to a mistake,” he said.
World Kitchen says they’re wrong. The company says it strikes the right balance in the degree of tempering. It tempers Pyrex enough to withstand temperature changes appropriate for its intended use, but it doesn’t highly temper it.
That’s because even though it is less likely to break, highly tempered glass, when it does break, breaks more dynamically and can result in “hundreds of fine glass slivers as well as the small dice.”
As proof of its excellent safety record the company points out that the complaints about Pyrex turned over to the 2 Investigators by the Consumer Product Safety Commission – just 66 of them — are unsubstantiated and very limited compared to the 369 million pieces it has sold since 1998.
The company says no injuries from shattered Pyrex are reported in CPSC surveys of emergency room injuries for 2005 and 2006.
All that together with the results of a test it commissioned from an independent laboratory “plainly confirms that Pyrex glass bake ware…does not present a safety risk,” the company said.
“I think it’s extremely fortunate that no one has been more seriously hurt by these flying fragments,” Freiman said.
Pyrex originally was made of borosilicate glass, a Corning invention, that enabled it go from the oven to the refrigerator and vice-versa.
Pyrex in Europe is still made of this type of glass.
Around 1946, Corning began making some Pyrex out of tempered soda lime glass. World Kitchen tells the 2 Investigators most Pyrex sold in the U.S. has been made of soda lime glass since that time., and that the transition was completed by 2001.
“Both versions of Pyrex glass bakeware were made to meet similar performance attributes and were safe for consumer use,” World Kitchen said in a letter.
Professor Bradt says the glass as it’s presently tempered is “very much more susceptible to fracture or breakage from temperature changes than the original Corning Pyrex, which is the classical oven-to-icebox glass.”
World Kitchen points out that there has never been a recall of Pyrex by the CPSC. And the CPSC told us it does not consider Pyrex to be a safety hazard.
Since Feb. 24 when the 2 Investigators began reporting this story, CBS 2 has received more than 100 e-mails from viewers about Pyrex experiences. If you have something you’d like to share about an experience with Pyrex, e-mail us.
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