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CMC 403 / ASHRAE 62.1 — Ventilation Rates for Acceptable IAQ

Updated May 22, 2026
Outdoor air ventilation rates by occupancy (CFM per person + CFM per sqft). Office 5 + 0.06, retail 7.5 + 0.06, restaurant dining 7.5 + 0.18, etc.

Used to size the OA component of RTU selection. The equipment-schedule workflow does not currently size ventilation — flagged as a follow-up for the engineer of record.

TAGS
CMC403ASHRAE-62.1ventilationIAQoutside-air
DETAILS
book
CMC 2022
section
403
mep calc workflow
q-equipment-schedule
SOURCES
🔗https://codes.iccsafe.org/content/CMC2022P1/chapter-4-ventil...
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