VENTILATION BASICS
The Swiss IAQ Specialists
Ventilation = replacing some of the air within the
rooms with “fresh air” (outside air).
CO2 is the primary byproduct of humans breathing.
CO2 has conveniently been used as primary indicator
to determine proper ventilation rates.
Significant cost to condition outside air rather than re-
circulated air.
VENTILATION TECHNOLOGY
Consider adopting “CO2 Demand-based Ventilation”
– Uses active CO2 monitoring as reference to
determine ventilation rate/duration.
– Adjust outdoor airflow in response to sensed
CO2 level to maintain proper ventilation for the
current population.
CO2 Demand-Controlled Ventilation Summary
CO2-based DCV is most often applied in
– Single-zone systems WITH
– Densely-occupied spaces AND
– Widely-variable population
Dilution
Insufficient Ventilation is the root
cause of poor IAQ
A first step to increase the air
quality is dilution of polluted indoor
air with fresh (or improved) air.
Exhaust-ventilation supports the
dilution effect.
The goal of Dilution is to reduce contaminant
concentrations in indoor air with a combination
of exhaust and ventilation.
Fresh or
improved Air
Indoor Air
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