IMC 2021 · Model

Chapter 4: Ventilation

21 sections in this chapter of the IMC 2021 model text — not Model's amended edition.

401.1 Scope This chapter shall govern the ventilation of spaces within a building intended to be occupied. Mechanical exhaust systems, including exhaust systems serving clothes dryers and cooking appliances; hazardous exhaust systems; dust, stock and refuse conveyor systems; subslab soil exhaust systems; smoke control systems; energy recovery ventilation systems and other systems specified in Section 502 shall comply with Chapter 5.

  1. 401.1Scope
  2. 401.2Ventilation required
  3. 401.3When required
  4. 401.4Intake opening location
  5. 401.5Intake opening protection
  6. 401.6Contaminant sources
  7. 402.1Natural ventilation
  8. 402.2Ventilation area required
  9. 402.3Adjoining spaces
  10. 403.1Ventilation system
  11. 403.2Outdoor air required
  12. 403.2.1Recirculation of air
  13. 403.2.2Transfer air
  14. 403.3Outdoor air and local exhaust airflow rates
  15. 403.3.1Other buildings intended to be occupied
  16. 403.3.2Group R-2, R-3 and R-4 occupancies, three stories and less
  17. 404.1Enclosed parking garages
  18. 404.2Occupied spaces accessory to public garages
  19. 405.1General
  20. 406.1General
  21. 407.1General

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IMC 2021 Chapter 4: Ventilation — Model Code | BuildSpec