Intent 1:
To limit the probability that the dislodgement of
flow-regulating dampers will go unnoticed and unrectified, which could
lead to an inability to regulate the airflow in ventilation systems,
which could lead to:
- when the damper is closed, inadequate ventilation or
excessive negative pressure, and
- when the damper is fully open in cold weather, thermal
shock to heat exchangers.
This is to limit the probability of:
- the inadequate control of airborne pollutants, or oxygen
and other components necessary for breathable air,
- the inadequate control of relative humidity, which could
lead to condensation on interior surfaces,
- where there is excessive negative pressure:
- 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, or
- cracking or premature failure of heat exchangers, which
could lead to the leakage of combustion gases into living space.
This is to limit the probability of negative effects on
the air quality of indoor spaces, which could lead to harm to persons.