Outdoor air
ventilation [cfm/occupant or cfm/sq
ft] vs.
total airflow [air changes per
hour]
Historical guidelines
Past
building codes
Current
requirements
Proposed
addenda to ASHRAE Std. 62-1999
Historical
Guidelines
Proposed by Dr. John S. Billings
in “Ventilation and Health”,
The Engineering Record, New
York, NY, 1893:
Offices
-
30 cfm
per person
Schools&
Churches-
40 cfm
per person
Legislature Halls -
60 cfm
per seat
Past Building
Codes
The
history of building codes in the
State of Wisconsin has left a
legacy of schools, offices and
commercial spaces ventilated at
1/3 to 1/2 of the current
minimum rate recommended by
ASHRAE:
Wisconsin Administrative Code,
Comm. 64.05(2)(a) [Table 64.05]:changed from 5 cfm/occupant
to 7-1/2 cfm/occupant in April
1996, but was “stayed” until
April 1997.