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Ventilation Requirement Calculator

Estimate zone outdoor airflow from occupancy and area using user-entered design rates.

Occupants

Area (m²)

Outdoor airflow rate per person (L/s/person)

Outdoor airflow rate per area (L/s/m²)

Air distribution effectiveness (Ez)

Results

Example: single-zone outdoor airflow

For 10 occupants, 80 m² of floor area, a per-person rate of 2.5 L/s/person, an area rate of 0.3 L/s/m² and Ez = 1, the calculated breathing-zone and zone outdoor airflow is 49 L/s (176.4 m³/h). These example rates are not a recommendation for all building types; use the correct rates from the adopted ventilation standard.

Related tools: CO₂ Ventilation Calculator · ACH Calculator · Air Handling Units

Formula and limitations

Vbz = Rp × Pz + Ra × Az; Voz = Vbz / Ez. Rates shown are editable examples, not universal requirements; select rates for occupancy and locally adopted code. Excludes multizone system calculations.

This tool provides educational estimates only. Verify design and safety requirements with a qualified professional.

Further reading: Reference source ↗. Explore other AirAlign Useful Tools.