I was cleaning the glass at my house and I think I scratched it quite a bit with a scraper. How can I tell if glass is tempered? Does this sticker mean it is?
If it is tempered it should have a similar stamp to that which says “TEMP” or “TEMPERED”, perhaps in a different corner even. You can also look at it with polarized sunglasses and see dark spots or streaks.
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Are you saying that the scratches show up as dark spots or streaks? I never
heard this before.
No, not saying anything about scratches. The question was how to tell if tempered glass.
For our part of the world the AS/nzs 2208 is our Australian / New Zealander standards and the grade A denotes it’s grade A safety glass which is only toughened or laminated and the TF means toughened float and the 4 is the thickness of the glass, not all toughened glass will have this stamp, here in oz we can order glass minus the stamp so in those situations keep a pair of polarised sunnies handy as these show up the stress points in the toughened glass, you will see the stress marks in the corners of the glass, you can sometimes see where the cooling jets hit the glass also, visually toughened glass also distorts the surface so you can look at the glass and try find a square/straight line reflected in the glass and this will be distorted if the glass is toughened.if there is no stamp and the corners of the glass isn’t visible such as when they are glazed into windows it becomes harder to detect as you won’t see anything using polarised sunnies, I can tell the difference between toughened, laminated and float glass just by knocking on it as they all feel different and found different but it takes experience to feel and hear the difference
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