What about mold in large buildings?
EPA has a number of resources available, you can start with the Indoor Air
Quality Building Evaluation and Assessment Model (I-BEAM). I-BEAM updates
and expands EPA's existing Building Air Quality guidance and is designed to be
comprehensive state-of-the-art guidance for managing IAQ in commercial
buildings. This guidance was designed to be used by building professionals
and others interested in indoor air quality in commercial buildings. I-BEAM
contains text, animation/visual, and interactive/calculation components that
can be used to perform a number of diverse tasks.
How to Identify the Cause of a Mold
and Mildew Problem.
Mold and mildew are commonly found on the exterior wall surfaces of corner
rooms in heating climate locations. An exposed corner room is likely to
be significantly colder than adjoining rooms, so that it has a higher relative
humidity (RH) than other rooms at the same water vapor pressure. If mold
and mildew growth are found in a corner room, then relative humidity next to
the room surfaces is above 70%. However, is the RH above 70% at the
surfaces because the room is too cold or because there is too much moisture
present (high water vapor pressure)?
The amount of moisture in the room
can be estimated by measuring both temperature and RH at the same location and
at the same time. Suppose there are two cases. In the first case,
assume that the RH is 30% and the temperature is 70oF in the middle
of the room. The low RH at that temperature indicates that the water
vapor pressure (or absolute humidity) is low. The high surface RH is
probably due to room surfaces that are "too cold." Temperature
is the dominating factor, and control strategies should involve increasing the
temperature at cold room surfaces.
second case, assume that the RH is 50% and the temperature is 70oF
in the middle of the room. The higher RH at that temperature indicates
that the water vapor pressure is high and there is a relatively