About the choice of fire protection for museum and art storage areas: One objection to the use of 'dry pipe' sprinkler systems is the somewhat counter intuitive proposition that the insides of the 'dry' pipes tend to rust because of ambient moisture and the ready availability of oxygen. The residual water in the pipes comes from testing the system (I think). If you do have a fire, you may expect to find items not destroyed in the fire water damaged, *and* badly rust- stained as well. I haven't seen this in practice, but heard it from a reliable enough source not to want to risk it. In the design of the National Gallery of Australia's new (off-site) art storage area, we plumped for a wet pipe system with individual on/off heat activated sprinkler heads, and a VESDA system. VESDA stands for Very Early Smoke Detection Apparatus. It was developed by our national scientific research body (CSIRO - an organisation so successful that successive governments have been moved to cut its funding and impose pointless reorganisations year after year). VESDA picks up very tiny quantities of smoke, but also includes several levels of warning so as not to provoke too many false alarms. Staff may have to do more than open the window to have a fag however... Bruce Ford (Head of Conservation, NGA)