ASHRAE Std. 62-1999:  “Ventilation for Acceptable Indoor Air Quality”

Research conducted by Lehmberg and Yaglou at Harvard University in the 1930s established outdoor air ventilation requirements based on the subjective acceptance of body odors.

12 CFM/occupant found to be the minimum outdoor air ventilation rate necessary to control body odors from sedentary adults (Yaglou, 1937)

 

The work at Harvard was based on the perceptions of unadapted individuals, i.e., visitors to the space.  Yaglou also found that 80% of adapted individuals (i.e., occupants of the space) deemed the odor intensity acceptable at 5 CFM/occupant. 

Proposed Addendum “n” (Second Public Review completed Sept 2001)

return to a floor value of 5 CFM of outdoor air per person to address occupant-generated odors and irritants (the “people component”)

additional outdoor air ventilation to address non-occupant derived sources, such as furnishings and finishes, cleaning products (the “building component”) 

The Standard 62 Committee explains:

“…it was decided that a code-intended standard should not be designed to satisfy the first impression of visitors, but rather should be designed to satisfy the building’s occupants.”