Sentence 9.32.3.13.(2)

Intent 1:

To limit the probability of insufficient vertical clearance, which could lead to:

• the blockage of intake openings by accumulated snow, or
• the ingress of dust or grass clippings.

This is to limit the probability of an inadequate supply of makeup air, which could lead to excessive negative pressure in dwelling units, which could lead to the spillage of carbon monoxide gas from fuel-burning appliances that are susceptible to spillage, which could lead to the acute poisoning or asphyxiation of persons.