Intent 1:
To limit the probability that the airflow resistance
of ducts will not be taken into account, which could lead to inadequate
ventilation where fans perform significantly below the required capacity.
This is to limit the probability of:
- moisture ingress from the ground,
- 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
- the inadequate control of relative humidity.
This is to limit the probability of:
- negative effects on the air quality of indoor spaces,
or
- the inadequate thermal comfort of persons.
This is to limit the probability of harm to persons.