Free Ventilation Rate Calculator
Calculate the required outdoor air ventilation rate for a space per ASHRAE Standard 62.1 guidelines.
sq ft
people
CFM
CFM
Total Outdoor Air
110 CFM
People Component50 CFM
Area Component60 CFM
Total Outdoor Air vs Floor Area
ASHRAE 62.1 Ventilation
Outdoor Air = (People x CFM/person) + (Area x CFM/sqft)
ASHRAE 62.1 uses a two-part calculation: a per-person rate for bioeffluents and a per-area rate for building emissions. Office spaces typically use 5 CFM/person and 0.06 CFM/sqft.
Example Calculation
1,000 sq ft office with 10 occupants.
- 01People = 10 x 5 = 50 CFM
- 02Area = 1000 x 0.06 = 60 CFM
- 03Total = 50 + 60 = 110 CFM outdoor air
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