Sentence 9.32.3.6.(3)

Intent 1:

To limit the probability of the inadequate distribution of outdoor air.

This is to limit the probability of the inadequate control of:

• airborne pollutants,
• oxygen and other components necessary for breathable air, or
• relative humidity, which could lead to condensation, 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.

Intent 2:

To exempt the principal ventilation fan from being interlocked with the circulation fans to comply with Sentence 9.32.3.6.(2), in circumstances where the forced air distribution system is equipped with controls that automatically activate the circulation fan at selected intervals, on the basis that the circulation fan will be activated to distribute outdoor air within the dwelling unit whether or not the principal ventilation fan is operating.