160.2(c)3 Mechanical Ventilation - 2022

Mechanical ventilation. Occupiable spaces shall be ventilated with a mechanical ventilation system capable of providing an outdoor airflow rate (Vz) to the zone no less than the larger of A or B as described below:

• A. The outdoor airflow rate to the zone (Vz) shall be determined in accordance with Equation 160.2-G; or
  

  Vz = Ra x Az (Equation 160.2-G)

  
  Where:
  Ra = Outdoor airflow rate required per unit area as determined from Table 160.2-B.
  Az = Zone floor area is the net occupiable floor area of the ventilation zone in square feet.

• B. For spaces designed for an expected number of occupants, the outdoor airflow rate to the zone (Vz) shall be determined in accordance with Equation 160.2-H;
  

  Vz = Rp x Pz (Equation 160.2-H)

  
  Where:
  Rp = 15 cubic feet per minute of outdoor airflow per person
  Pz = The expected number of occupants. The expected number of occupants shall be the expected number specified by the building designer. For spaces with fixed seating, the expected number of occupants shall be determined in accordance with the California Building Code.
• Exception to Section 160.2(c)3: Transfer air. The rate of outdoor air required by Section 160.2(c)3 may be provided with air transferred from other ventilated space if:

1. 1. Use of transfer air is in accordance with Section 160.2(c)8; and
   2. The outdoor air that is supplied to all spaces combined is sufficient to meet the requirements of Section 160.2(c)3 for each space individually.