[Porsche-O-Phile]

Nobody is using halon anymore - if you're in an area with a halon system and it goes off, you either get out immediately, find and don a respirator/supplemental O2 immediately, or you die.

The new "clean agent" type systems are argon-based and will not kill you if you find yourself in a space that happens to have one when it goes off.

Usually there are countdown alarms with either type of system based on multiple detections (i.e. two or more smoke detectors) or a pull station will blow the bottles immediately with no countdown. Either one is considerably more expensive than a typical water-based system and must be checked/maintained on regular intervals.

You can use a pre-action system if you're concerned about someone whacking a sprinkler head and ruining your house. With those, a "first alarm" (first smoke detector or heat detector) will run a pump to charge the (normally empty) pipes. Then if there's enough heat to pop the head, water will flow. This is a much safer type of installation where inadvertent damage to property is a consideration.

With any type of residential sprinkler system you should be able to negotiate a much better rate on your homeowner's insurance. And municipalities are starting to lean towards requiring these for new residential construction (even single-family detached in some areas).

It's worth looking into. For starters, check NFPA and/or consult a professional (yes, I know that's a little self-serving, but really - they can point you to a lot of good information).

EDIT: Just saw javadog's post and pretty much agree with it. With gas suppression systems you need a pretty well-sealed environment (you'll need an engineer to do a pressure test to make sure the agent won't just disperse and will remain in sufficient concentration in the space to snuff out the fire). You certainly can tighten up your envelope in order to get the proper seals but it won't be cheap.