Hal Levin and I have had this discussion before. I am very much
in favor of the concept of demand controlled ventilation DCM,
however the means of determining the demand must be somewhat
instantaneous. E.g., take the case where the building is at
minimum ventilation overnight and an assembly room fills to
capacity with 800 people at 8:00 AM. How long will the response
time of a CO2 sensor be before the air makeup shifts into maximum
fresh air mode? For this reason I suggest that another means of
measuring demand be utilized, perhaps by "counting" occupants
(trip beam) or determining occupant density PSF (infra-red
sensor).
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Loren E. Abraham, AIA, IDSA
Charlottesville, VA
Vc: 804 296 4197 Pg: 804 963 1511 Fax: 804 971 3729
© 1997 Daybreak Technologies Inc. / Environmental Research Group
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