Question:
I have an intact Red Comet Fire Extinguisher. Does anybody know anything about these? I understand how it works, when heat melts the seal, the spring loaded piston breaks the glass and the fluid inside douses the fire. This extinguisher is mounted over the electrical entrance in the house we just bought. Any idea how old? What is the chemical inside? Are they still being made?

Answer: You appear to understand how they were SUPPOSED to work, but in actuality, the fluid released (carbon tetrachloride, I believe) releases toxic fumes that can be fatal! If you want to display this item, disassemble and remove the fusable link and spring. I also suggest you relocate it away from your service box (again, for safety reasons). Red Comets were made into the 50's and, as a rule, are common and inexpensive. Little, if any, value will be lost with this modification which could save your life.