Sentence 9.3.1.8.(1)

Intent 1:

To limit the probability that substandard admixtures will be used, which could lead to the spalling or premature deterioration of concrete.

Where concrete supports or is used in the walls of chimneys or fireplaces, this is to limit the probability of the inadequate performance or premature failure of concrete under expected environmental or structural loads, which could lead to the failure of these walls.

This is to limit the probability of the leakage of combustion products, which could lead to negative effects on the air quality of indoor spaces.

This is to limit the probability of harm to persons

Intent 2:

Where concrete supports or is used in an environmental separator, to limit the probability of the inadequate performance or premature failure of concrete under expected environmental or structural loads.

This is to limit the probability of:

• the compromised integrity of the environmental separator, or
• an inadequate resistance to air and moisture transfer through the concrete.

This is to limit the probability of:

• pollutant ingress (from the exterior or from adjacent interior space, including soil gas, combustion products from parking garages, and particulates),
• precipitation ingress,
• condensation,
• the ingress of moisture from the ground, or
• the compromised thermal performance of components intended to provide resistance to heat transfer.

This is to limit the probability of:

• the generation of pollutants from biological growth or from materials that become unstable on wetting,
• deterioration, which could lead to further compromised integrity of environmental separators, or
• an inadequate control of indoor air and surface temperatures, drafts, relative humidity, or water accumulation.

This is to limit the probability of:

• negative effects on the air quality of indoor spaces,
• the inadequate thermal comfort of persons, and
• contact with moisture.

This is to limit the probability of harm to persons.