The Chicago Fire Department is testing a system developed at the University of California, Berkeley. Given the cute acronym F.I.R.E. for Fire Information and Rescue Equipment, the system tracks fire fighters throughout a burning building. The FIRE project has a web site here.

The FIRE system, which the Chicago Fire Department began testing in the
spring, consists of two elements—SmokeNet and FireEye. The SmokeNet is
a wireless network using Moteiv's Tmote Sky wireless sensing platform and sensors, as well as its Boomerang software, which enables wireless sensor devices to register and report changes in the environment to
firefighters. The sensors, which use two AA batteries, can be installed
in smoke detectors, on ceilings, or in door jams throughout a
commercial building, says Paul Wright, chief scientist for CITRIS [the Center for Information Technology in the Interests of Society], a public-private partnership that
creates information technology solutions for social, environmental and
health-care problems.

The sensors use active 2.4 GHz RFID tags with a read range up to 100 feet. As part of its pilot program, the Chicago Fire
Department has installed these sensors throughout one of its
facilities. The FIRE system is also installed in some UC Berkeley
buildings and is being examined by several other cities, Wright says.

The story goes on to describe how the rest of the system is architected - check it out. The down side of the system is that you have to have all these sensors deployed in the building before the fire.

Pictured right is a ZigBee component radio.