Impact or safety Glass

I’m also an an affiliate member of the Florida Building Officials Association which has a similar forum as this. Most times it is more of a technical disscussion anout code interpretation and such, but sometimes I can pick up a good nugget.

How many times have you been on an inspection and a home owner is telling you that those glass doors are “Hurricane Doors” and have a product approval, but you are unable to read the poorly etched image on the glass and then after doing the finger tap test you are suspicious that the glass is not laminated but safety (tempered) glass. The following is pasted from a B.O.A.F. post and was confirmed by a later post from the manufacturer PGT.

An interesting point about inspecting windows. Pull out a Bic lighter and flick your bic next to the window. Look at the flame in the window. If you see two flames in the window it is usually tempered glass. If you see four or more reflections of the flame it is most likely missal impact resistant. Each layer of the window has a different diffraction rating and creates a separate reflection of the flame. fake and counterfit stickers are available. Don’t be fooled. this test won’t tell you what the window is but it will tell you if it is not what the sticker says

Same goes for a laser pointer! just angle it slightly and you will see the different layers from the refracted light.

Nice advice. I had heard of using a pointer but imagine a lighter would be easier to see. At least with my old eyes :slight_smile:

I used a laser pointer in the past to do such.

Another nice point, tap on tampered glass and then your wind shield of your car. The sound difference is very similar to laminated impact glass.

Nice post Mark. Much appreciated. Don’t smoke but will start carrying a bic from now on!


Bert you may already be carrying a laser pointer type of instrument

Come to think of it I am. Never used it for that though. I haven’t run into any questionable scenarios but definitely going to try it out the next chance where the home has impact glass or supposed impact glass.


You still need documentation. This just tells me if I am going to look or ask for it.

Agreed John. I’m sure they’re not just going to accept a picture of four red dots claiming the glass to be impact rated. But definitely a good starting point from there.


Not impact rated…No need to go further…

Yep, good example of why you cannot rely upon just the MDCA sticker for a window. They are not all impact rated.

But I would have just looked up the NOA instead of burning my fingers…just goofin

You would be correct Tom. And here is the actual NOA…


Notice in the fourth pic I used the laser from my infrared thermometer.

Agree with John! Take a photo of the etching or verify via the paperwork that might be available to the HO at time of install. Bottom line is, CYA. For those of you that are ex military, you should know what CYA is.

I wish all NOA’s were this easy too look up.

I carry a laser pointer type of instrument. But I don’t think the client’s would appreciate me using the crimson trace. :mrgreen: