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IMC Chapter 4 — Ventilation

Updated Mar 26, 2026
Mechanical ventilation outdoor air rates per ASHRAE 62.1, exhaust requirements, energy recovery.

IMC Ch4: outdoor air per Table 403.3.1.1: office 5cfm/person + 0.06cfm/sf, classroom 10+0.12, retail 7.5+0.06. DCV required >150 occupants. ERV required when exhaust >5,000 cfm and >70% of supply. No corridors as return paths above I-2/I-3.

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IMCventilationoutdoor-airASHRAEexhaustERV
DETAILS
code year
2024
code system
IMC
code section
Chapter 4
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