and when i was able to walk the site which, again, was a great gift for the audience to understand it in real-time. this is what it looks like from their perspective. okay? that is not just put an extinguisher on it, it's just a mattress. and what does that do in terms of just choking off opportunity? >> you know, we were -- feared that -- 9/11 we feared that with the rescuers that were underneath trying to save victims in the building. firefighters, themselves. how long could they live in that? go back even to the pentagon. we know a lot of our brothers that actually had to go in and out of that building while the fires were still active. actually, absorbing a lot of that carbon monoxide. >> carbon monoxide is always a problem with fire. count know what is burning, though. household chemicals, what's in vehicles, what is in building equipment. >> all of it. all cancer-causing materials, absolutely. >> and obviously, very noxious to the people who are inside. >> 100%. >> and then, you have another front of a fire on the back side that i was able to take video of