Positive pressure ventilation systems

Our museum plans the addition of a new entrance foyer with a new
connecting stairway to the exhibition spaces, which are all on the
second floor. The plans, which have just been submitted to the
conservation department for comment, are for the doors at the top of
the 2-meter-wide staircase to be kept open during opening hours. The
ventilation engineer claims that a positive pressure ventilation
system will maintain the environment in the galleries even with
these doors propped open. The stairs are quite open in design. The
foyer will be heated but not environmentally controlled and will
also contain a cafeteria and small kitchen. There is a double door
as the outside entrance into the foyer.

The conservation department here is very concerned about whether the
positive pressure alone will satisfactorily exclude foyer air from
the galleries. Can anyone offer advice or experiences they have had
with similar systems? Wouldn't it be very expensive to run a
positive pressure system with doors standing open? Does anyone know
any specifications for how much air pressure we would need?

Janine Wardius
Conservator of Paintings
Bergen Kunstmuseum,
Rasmus Meyers Alle 3, Bergen, Norway

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                  Conservation DistList Instance 12:11
                   Distributed: Friday, July 17, 1998
                       Message Id: cdl-12-11-018
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