Relative humidity control in microenvironments

Robyn Pender (Cons DistList Inst. 10:9) recommends RH control using
saturated salts.

During a 2 year study (in the mid 80s) of corrosion of metals in
timber  we used saturated salt solutions to control RH.  It gave
good ( few %), long term (months) control only when:

    *   the chamber was reasonably vapour tight

    *   the solution was gently stirred

    *   there was moderate circulation of the chamber air.

We used a controlled temperature and chose the solutions for minimal
temperature dependance of RH.

Graham Sussex

                                  ***
                  Conservation DistList Instance 10:10
                  Distributed: Saturday, July 13, 1996
                       Message Id: cdl-10-10-002
                                  ***