Mist fire suppression systems

The following messages were posted on the Objects Group discussion
list with little response. Any advice from the DistList?

The following message was posted by Jessica Johnson for someone not
on the OSG list:

    Currently several NPS parks are in the design phase for the
    installation of a water mist fire protection system. As with
    many fire suppression systems, many of the lines will run
    through unheated areas that are prone to freezing temperatures.
    The usual (and least expensive) means used by the company for
    preventing freezing within the lines is the insertion of an
    antifreeze (Propylene Glycol). Since  these are some of the
    first installations in museums for this company (usually a
    distributor to cruise lines), they are not aware of any
    potential hazards posed by this antifreeze to a museum
    collection during a disaster. Has any park installed a fire
    suppression system (preferably a mist system) with an antifreeze
    in the lines that knows more about the clean-up? Do any
    conservators know of any potential problems with the clean-up of
    this material?

R. Kerschner Replied:

    I believe this system has significant potential for use in
    Museums, especially in historic buildings. It is essentially a
    highly effective fire suppression system that could quickly
    extinguish a fire in a historic building without introducing
    much water or soaking the contents of the building. I believe
    that we are talking small amounts of Propylene Glycol, pints or
    quarts, not gallons. This may or may not make a difference if
    even very small amounts can cause corrosion to metals or damage
    to paint films.

    Also keep in mind one is probably not talking about long term
    contact between the antifreeze-water mixture and the artifacts.
    Hopefully within minutes or hours of discharge, conservators or
    other respondents will be wiping moisture off all the artifacts
    that have been exposed to the mist.

    Finally, any potential damage from the Propylene Glycol should
    be weighed against the potential damage from fire, or soaking
    with hundreds of gallons of water from conventional sprinkler
    systems or fire hoses.

    A dry pipe mist system may be ideal. I believe this is possible,
    but additional cost may be a factor.

Richard L. Kerschner
Director of Preservation and Conservation
Shelburne Museum
PO Box 10, Route 7
Shelburne, VT  05482
802-985-3348 Ext 3361


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                  Conservation DistList Instance 13:48
                  Distributed: Friday, March 24, 2000
                       Message Id: cdl-13-48-039
                                  ***