I work for a Museum of Natural History that is housed in a building constructed at the turn of the century. In order to comply with contemporary fire safelty regulations, we are being asked to install a fire sprinkling system into our exhibition halls. I am under the impression that there are basically two types of systems; wet and dry. Wet being that the water is held under pressure at the sprinkler head and dry being that the water is held back at a valve check point. I would appreciate any feedback as to the advantage or disadvantage of either system as well as any precautionary measures to consider for protecting our collections in light of this addition into the exhibition environment. Thank you, Bruce Scherting