Drying Chamber Air Turnover
Actual ACH from air-mover and dehu CFM and gap to target ACH.
Example
You enter
- Chamber volume (ft^3) 1500
- Target ACH 60
- Air mover total CFM 1200
- Dehumidifier CFM 250
You get
- Actual ACH 58
- Required CFM 1500
- Gap to target 50 cfm
Checked against published worked examples from: IICRC.
Details, formula, and sources
Formula or tableACH = ((air_movers_total_cfm + dehu_cfm) × 60) / chamber_volume_ft³. Target ACH is entered (default 60). Gap (cfm) = max(0, target_ACH x volume / 60 - (air-mover + dehu cfm)).
Source and editionIICRC S500-2021 §12 (Drying Process) by name.
Free accessIICRC licensed; principles free in published water-damage-restoration training literature.
What governsEstimate. AHJ and licensed professional govern.
API field nameschamber_volume_ft3, target_ach, air_mover_total_cfm, dehu_cfm, actual_ach, required_cfm, gap_cfm
- Target ACH entered (default 60); for reference, IICRC S500-2021 typical figures by class are Class 1 ≥ 6, Class 2-3 ≥ 8, Class 4 ≥ 10IICRC S500-2021 typical