Intent 1:
To limit the probability of the operation of exhaust
fans without the simultaneous operation of related makeup air fans,
which could lead to excessive depressurization, which could lead to:
- the ingress of soil gases (such as methane and radon),
- the spillage of combustion products from fuel-burning
appliances that are susceptible to spillage, or
- moisture ingress from the ground, which could lead to
the generation of pollutants from biological growth or from materials
that become unstable on wetting.
This is to limit the probability of
negative effects on the air quality of indoor spaces, which could
lead to harm to persons.