We need to replace the outer glass on our oven it shattered while cooking

Yes you can, in the emergency, but take care that the remaining glass will be at oven temp. You may want to shield it with a piece of plywood or stiff cardboard, taped on.
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replace it with heat glass 1200%C

I depends on how old your oven is. If you're lucky you may be able to get a replacement glass. If not take some measurements and see a glass supplier. You will need a piece of tempered glass.

You must replace it with the glass as supplied by the manufacturer, as it is is special heat tempered glass.

gget a new door

Lisa, I do not have a solution, but have the same problem. My KA superba micro has been used about 10 times. While it was off, and while no one was home, the outer glass in the door shattered. I suspect this may be a defect.

It is not a fault with the door, and this sort of event occurs quite often, so is not uncommon.
All sorts of things can cause this, sudden change in temp, getting the glass wet whilst it is still hot, a knock or bang form an earlier time could have weakened the glass.
The list is quite long..
Depending on your household insurance, some policys cover for breakage of glass fittings, would be worth checking.
Plz rate my solution
.Thanks.

will need a model number to tell you the correct price ... most will have to replace the door... you can also give sears a call .. if you gripe loud ... they may replace it for you...

contact GE; they should have replacement glass in stock.