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Warning that Pyrex Glass Cookware Can Explode-
Summary of the eRumor: The eRumor talks about what
it describes as “exploding Pyrex.” It says that the popular ovenware
has been unsafe ever since the Corning Company sold the Pyrex brand to a
company named World Kitchen. It also claims that the product became
inferior because it was now made of soda lime glass instead of borosilicate glass.
One final claim is that World Kitchen is not an American company.
don’t know who the original author is of this email or his or her
motives, but there is a lot said about Pyrex and the company that
makes Pyrex that is incorrect.
Pyrex is one of the most widely used products in American households
and has been used safely for decades.
According to World Kitchen, the makers of Pyrex, there has never
been a recall of Pyrex or any concern about its safety on the part
of the Consumer Product Safety Commission.
Like all glassware, Pyrex needs to be used according to
instructions. At the time of our investigation we found on the Pyrex website
an advisory to consumers not to
subject the product to extreme temperature changes, such as putting a
Pyrex dish directly on a burner, under a broiler, adding liquid to a
hot dish or placing a hot dish on a cold or wet surface. Under
those circumstances the glass can break.
The claim that the current makers of Pyrex abandoned borosilicate
glass in favor or poorer quality soda lime glass is false.
World Kitchen told TruthOrFiction.com that Pyrex has been made from
heat-strengthened soda lime glass for about 60 years and that the
switch was first made by Corning, not World Kitchen. The company
added, “Consumers should know that soda lime glass, such as that
used to make PYREX glass bakeware, is significantly more resistant
to breaking on impact than borosilicate glass and comparably
resistant to breakage caused by severe temperature changes.”
also false that World Kitchen is not a U.S. company. It is an
American firm and Pyrex is manufactured in the U.S.A..
from the Pyrex website
bakeware product can break if it
is not used properly. For that
reason, we want to remind
consumers to review the PYREX®
Safety and Usage Instructions
provided with our products.
While not a substitute for
reviewing the entire Safety and
Usage Instructions, set forth
below are selected highlights.
BAKEWARE SAFETY AND USAGE
NEVER use on top of the
stove, under a broiler, in a
toaster oven, or place over
oven vent or pilot light.
AVOID severe hot to cold
DO NOT add liquid to
DO NOT place hot
dish or glass cover in
DO NOT immerse hot
dish in water
DO NOT place hot
dish on cold or wet
Handle hot ovenware
and glass covers with
ALWAYS add a small
amount of liquid to the
vessel prior to baking foods
that release liquids while
DO NOT overheat oil or
butter in microwave. Use
minimum amount of cooking
DO NOT use or repair any
item that is chipped,
cracked or scratched.
To loosen baked-on-food,
allow glass to cool, then
If scouring is
necessary, use only plastic
or nylon cleaning pads with
Failure to follow these
instructions can cause immediate
or later breakage which can
result in personal injury or
Posted 10/20/09 Updated
A real example of the eRumor as it has
appeared on the Internet:
About 5:30 PM there was a loud bang
from the oven. Sylvia opened the oven door and the Pyrex dish had shattered into a million pieces. The roast beef (our first in many months)
was peppered with small shards of very sharp glass. Normally,I am quick
to inform Sylvia she did something stupid. However, this time she was
nowhere near the stove when it blew. I shoveled the glass and the now
mashed potatoes into a bucket with two putty knives. I then sucked the
remains with the shop vac. I let everything cool down and then scrubbed
the oven with Simple Green and some hot soapy water. It took over an
hour to clean up the goo. Upon completion I ran the oven empty to see if
the temperature controller was working okay. I suspected the oven got
too hot and the dish simply blew. This was not the case however. The
oven came up to temperature and cycled normally. We threw a disgusting
frozen pizza in the oven and it cooked okay.
What is going on?
I Googled exploding Pyrex dishes and got ten million hits.
Exploding Pyrex is very common.
Here is the story.
A long, long time ago in a country we all know and love was a company
named Corning. They made Pryex dishes. The material they used is called
borosilicate glass. This stuff is indestructible. But like everything
else, the Bottom Liners had a great idea: sell the technology to another
company. The Chinese discovered that using soda lime glass was almost as
good as borosilicate glass and a lot cheaper. Today, Wal-Mart is the largest distributor of Pryex products. Corning not only sold the technology
to a company called World Kitchen, they also sold the rights to the
original Pyrex logo. Seamless. The consumer will never know.
Now it seems people are getting hurt using soda lime Pyrex. We were
lucky because the dish broke while the oven was closed and the damage
was limited to the oven cavity. Others have been less fortunate. Some
dishes explode when they are lifted from the heating rack in the oven
with devastating results. Some people are heavily scarred. World Kitchen
is in denial. They say that the dishes are another brand, not theirs.
Contrary to their denials the victims usually have more than one of
these dishes and the Pryex logo is clearly visible.
If you buy a Pryex dish beware. The label on the front says oven safe,
freezer safe, microwave safe. The instructions on the back tell another
story. You cannot move a soda lime Pyrex dish from the freezer to the
oven and expect it to survive. The fine print goes on and on about what
you are not allowed to do with the Pyrex dish. The fine print has
prevented World Kitchen from being sued becaus e they have warned the
consumer that their Pyrex dishes are junk from the get go. And they are
the same price as the original Corning dishes. What a bunch of losers we
all are for buying this crap.
What to do?
If you own borosilicate Pryex dishe s no fear. They have to be more than
25 years old to be sure they are indeed Corning dishes. I am not sure if
the old Pryex dishes have anything stamped in them that indicates they
are made by Corning. You may continue to use the soda lime dishes for
holding stuff. Just do not attempt to roast or microwave with them as
the hazard is very clear.
The reason the soda lime dishes let go is that over time they develop
micro-cracks. Once a few micro-cracks are present and once some liquid
finds its way into the cracks you have the bomb situation. The liquid is
like shoving a crowbar in the dish and pulling it apart. Super heated
liquids expand rapidly and it is the super heated liquids that force the
soda lime glass to shatter into tens of thousands of shards.
Since Corning no longer makes Pyrex and Sylvia proudly holds a large
collection of the soda lime Pyrex, we decided that one bomb in the
kitchen is enough. The Pyrex dishes will go bye-bye in this week’s
trash. I do not know what we will use for cake and pie dishes going
forward . If you have some suggestions we are listening.
I strongly urge you not to use the soda lime Pyrex for the oven,
stovetop or microwave. The slightest invisible crack is all it takes to
have a mess and a possible injury.
As to World Kitchen: them and their cheap dishes. In case you are
wondering: World Kitchen is not a USA company.
2 For 1
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