I don't recall all the details, but there were several people who had been badly burned, and the EMTs sprayed them with foam--partly to put the fire out, but partly for some kind of protective covering.
Then I got burned, too. My whole left arm was down to the bone, black and charred, and other parts of me as well. (No pain--I rarely have tactile sensation in dreams.) When the EMTs got to me and sprayed me with the foam, I realized that it wasn't just to put out fire or for some esoteric medical purpose. It was supposed to hold my body together till they could figure out what to do.
Never dreamed I was literally falling apart, before. :P
On the plus side: actor Jim Beaver was in my dream, which was kind of awesome. I think he was with or directing the EMTs.