To minimize the risk of malfunction, interference,
damage, tampering, lack of use or misuse.
Objective:
OH1.1
APPLICATION:
Protection of exterior openings for outdoor air intakes
and exhaust outlets, in heating, ventilating and air-conditioning systems,
in buildings described in Sentence
1.3.3.2.(1) of Division A.
heating systems, including requirements for combustion air,
and air-conditioning systems other than those serving individual dwelling units, as stated in Sentence
9.33.1.1.(2), and
air duct distribution systems serving heating systems in which
the rated heat input exceeds 120 kW, as stated in Sentence
9.33.6.1.(2).
INTENT:
To limit the probability that:
a lack of shielding will lead to the entry of water from rain
or melting snow into the system, or
a lack of screens, or screen mesh that is too large, will lead
to the entry of birds or animals into the building, which could lead to damage
to equipment.
This is to limit the probability of negative
effects on the air quality of indoor spaces, which could lead to harm to persons.