During some training we were discussing how best to cut Lexan glass and how best to breach Reinforced Gypsum.  We don't run into these materials much in my area.  Perhaps, some of the firefighters in Tornado Alley and the Hurricane areas can lend some of there knowlege and experience...

What saws work best?

What blades work best? (I found one post mentioning a Rotary Saw with a "Chunk Carbide" blade)

What training methods are best?

If you are cutting Lexan glass with a rotary blade are enough fumes produced to warrent masking up?

Thanks for any tips or help

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I remember reading an article years ago about cutting lexan glass and from memory they recommended a circular saw??? I can't remember specifics, but I think it was in either the FireRescue or Firehouse magazine....
I have heard that using a can of canned air upside down sprayed onto the lexan in order to freeze it, and then striking the area to cause it to shatter. When I had used to still race we would also use a angle grinder to cut, and shape the lexan but it didn't always work the best.
If you can attack the edges of the windows, it might be easier to just pry the window pane out intact instead of trying to break or cut the glass. You can also use a circular saw and cut the window frame out of the structure - this can be easier than trying to cut the armor glass. A Skilsaw with a cross-cut blade works well on wooden siding, walls, OSB, etc. It's also easier to handle and is safer than trying to handle a K-12 or chainsaw at head level or higher.

Breacking reinforced gypsum board - find the seam, pop a hallingan duckbill or pick in, and pry it out if you can.
Thanks for all the great input so far...it's awesome having a discussion board you can turn to while continuing to research...walk away, comeback and boom have some great feedback! Thanks again
I've heard the Tempest chainsaw can do it, but have never seen it personally.
You can cut Lexan with a circ. saw with "Chunk Carbide" blade, it will work. We cut aircraft windows with them for training. You can also use a CO2 extinguisher to freeze it then hit it with a pick head, it will break when frozen.
I don't know about Reinforced Gypsum.....
Do you always have a circular saw with a Chunk Carbide blade and/or a CO2 extinguisher with you when venting windows?

If not, you might just want to attack the window frame and remove the Lexan intact. It can be much quicker than running back to the rig for more tools.
Yes we always have a Chunk Carbide blade on our circ saws... and no we do not carry a CO2 extinguisher with us. If you use CO2 you can break the window with a pick head axe, it just takes a lot more time.
We can cut thick aircraft cockpit windows with a circ saw and it doesn't gum up. Horizon/Alaska air has donated several old replacement aircraft windows to us for training over the past years, so we have played with how to cut into them and break them.
You carry a circular saw just to do routine outside vent?

You use a circular saw to vent 2nd floor or 3rd floor windows instead of just venting them with a pike pole or a ladder tip?

Just wondering - how does your technique work if the armored windows are above grade?

I also have some doubts that old aircraft windows are the same type as modern hurricane-resistant windows, or that the saw blade will always work the same on the new structural windows.
I do not generally use a circ saw for "routine" vent. I have used them to cut roll up doors and metal siding. They are effective on Lexan windows if you have the right blade.
I have also used them to cut aircraft windows. They are sent to us in their frames and are in great shape, they are just past their service life. The CO2 was something we used in the military to break cockpit windows on fighters, it worked back then.
I don't know about the hurricane-resistant windows, wrong coast, but we do have some earthquake resistant materials floating around here.
As far as a "my technique" on armored windows above grade... well I don't have a technique. If it is the laminated safety glass, then treat it like Lexan and use a circ saw or chainsaw with carbide blade. I have never ran into second or third story armored windows... I suppose if I couldn't break it with a pike, then I would have to use a ladder to get all the way up there to use a saw. What is your technique for third story armored windows?
Either pry the armored window out intact or remove the entire window frame.

Attacking above-grade armored windows is obviously not as easy as just breaking out regular glass from grade level with a ladder tip or a pike pole. You have to place and climb a ladder, you don't have nearly the leverage you can get while standing on the ground, and you may have to attack the window/frame from one side, them move the ladder and attack the window/frame from the other side.

As for the Co2 trick, it worked on 1979 AMC Javelins with Lexan hatchback windows. I just don't know if it will work on modern structural windows are not. The structural windows don't necessarily have the same thickness or composition as the fighter or 1979 Javelin windows, so the CO2 trick might not work. I'd like to see some testing to make sure it works before I tell anyone else that it works.

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