Apparently a regular electrical fire would destroy the Mars Mission and kill all the astronauts. That's what researchers discovered in the Utah Desert last month.
Scientists take turns living outside Hanksville, Utah, for stretches at a time performing experiments to prepare for a human-powered mission to Mars in the near future. Earlier this month an electrical heater in the greenhouse malfunctioned and caught a piece of wood on fire, which spread. When one of the four researchers found it, the fire was 10 feet tall. Every fire extinguisher in the facility was used and the researchers ended up throwing buckets of water on it. A firetruck arrived hours later to investigate the cause.

The crew tried to carry on for a few days, but ended up voting to go home.

Ironically, this was not a "BioDome" experiment. The researchers were not trapped for months or years. They were actually the 146 crew to use the facility and after a temporary greenhouse was erected the 147th crew arrived two weeks later to start.

Maps.Google.Com