Re: Foil
"The surface of aluminum has the ability NOT TO ABSORB, but TO REFLECT 95% of the infrared rays which strike it. Since aluminum foil has such a low mass to air ratio, very little conduction can take place, particularly when only 5% of the rays are absorbed".
I got the above from the below link:
http://www.radiantbarrier.com/physics-of-foil.htmFoil is probably the best material to radiate/reflect heat and if you look around the internet it used by many in barbeque set-ups.
I am not into physics but know from experience it works great as a heat shield. As for burning up, it will not burn up when used in low and slow smoking. If you line your grill with it like shown at chef steps it will not burn or melt as it is reflecting the heat. It might burn if you place lit charcoal on it, but I am not sure why anyone would want to do this. The Reynolds foil you buy at the supermarket is not toxic.
My own preference is to generate searing heat using charcoal rails or Weber baskets and doubt I would waste foil on the chef steps set up. But for low and slow cooking foil is the best heat shield (e.g.) if you want to keep your food that is closest to the charcoal from being burned on one side or to re-direct heat. I can easily get a 5 hour burn at 250 without reloading using a Weber basket, charcoal rails, and a foil heat shield. With only the charcoal rails as described in previous posts I can set up a chamber that is larger and holds more charcoal than the smokenator or the SnS.