Yikes! I set a Silpat on fire!
..and I didn't even know this was possible. I was broiling some cut tomatoes on a baking sheet lined with a Silpat that didn't quite fit (it was longer and thinner than my baking sheet) and, a corner of it accidently came into contact with the heating element when I turned the sheet halfway though cooking..
When I opened the oven a few minutes later, some white ashes flew out, and I noticed they were from the now-burnt-off corner of the Silpat. Thankfully, none of them landed on the tomatoes.
I thought Silpats were pretty much fireproof, at least at home cooking temperatures. Exactly how much abuse can these things take??
I have a small toaster oven sized Silpat I've abused the heck out of over the psat 5 years or so. It's enver caught fire, but after so many years of daily use in my toaster oven, often when broiling something or when using the toaster function to toast some nuts....it's completely black and now no longer nonstick. I need to replace it and am having trouble finding the same size.
Anyway, my point is they take a licking but if you use it a lot for high heat cooking it will eventually give out!
Fireproof is one thing, but the heating element, especially at the broil setting, is really really really hot. I couldn't find any actual numbers, but I think it's in the 1000+ F range (http://www.processassociates.com/proc...).
The manufacturer rates them -40°F to 482°F - fine for most home applications (although perhaps not great for actual broiling which could get into the 500 range).
With pretty much anything, if making direct contact with a glowing coil all bets of heat/fire resistance are off.
You're right - - the Silpat mat (or any silicone bakeware brand) will catch fire if in direct contact with the heating element. Ex: my mom left the silpat mat in the oven, and forgot it there. Next time she baked, she preheated the oven to 500 degrees, slid her baking tray in, and never saw the silpat. The flexible silpat rolled to the eithe rhte back of the oven and eventually to the bottom of the oven. Guess what? Major oven fire...we couldn't even figure it out, because we didn't know what that burning roll was in the back of the oven. Very scary. We couldn't put it out with baking soda....(which was necessary because she was cooking something in on another tray with oil. We had to call the fire dept....we did manage to put it out by the time they got here. ...but it could have gone either way. So much smoke it was unbearable...had to fan the place out with the fire dept equipment.
So...moral of story is that fire-resistant/proof only goes so far.
NEVER keep your silpat in the oven.
The reason she left it there was because it was still very hot and she wanted it to cool off in the oven rather than put it on and risk damaging any other surface in the kitchen. Understandable...but the next person will not anticipate it being there...especially if it is on a different rack or of a color that blends in with the oven....or if you're not using your oven light.
Cheers and good luck.