What types of mechanical ventilation are required by the ASHRAE 62.2 Standard?

The types of mechanical ventilation include:

  • Local ventilation is intended to exhaust airborne contaminants at their source.
    • Full bathrooms
      • 50 CFM (25 L/s) for demand controlled exhaust.
      • 20 CFM (10 L/s) exhaust if operated continuously.
    • Kitchens
      • 100 CFM (50 L/s) demand-controlled exhaust if range hood installed directly over a range or 300 CFM (150 L/s) if not directly over the range.
      • 5 air changes per hours continuous exhaust ventilation if the kitchen is “enclosed”. An enclosed kitchen is defined as a kitchen whose permanent openings to interior adjacent spaces do not exceed a total of 60 square feet (6 square meters).
  • Dwelling-unit ventilation is intended to serve as dilution ventilation.
    • The CFM (L/s) minimum requirement is based on 1) the area of the living area and the number of occupants (bedrooms).
      • The minimum requirement for fresh outdoor air is supplied by natural air leakage (infiltration) and mechanical ventilation (exhaust, supply, or balanced).