Ventilation Rates in U.S. Office Buildings From the EPA Base Study.
Ventilation Rates in U.S. Office Buildings From the EPA
Base Study.
(2169 K)
Persily, A. K.; Gorfain, J.; Brunner, G.
Indoor Air Quality and Climate, 10th International
Conference. Indoor Air 2005. Proceedings. September
4-9, 2005, Beijing, China, 917-921 pp, 2005.
Sponsor:
Environmental Protection Agency, Washington, DC
Keywords:
ventilation; office buildings; carbon dioxide;
databases; standards; ducts; equations
Abstract:
The EPA BASE study involved indoor environmental
measurements in 100 U.S. office buildings. This paper
presents an analysis of the measured outdoor air
ventilation rates, including comparisons with the
requirements in ASHRAE Standard 62. The outdoor
ventilation rates measured using duct traverses at the
air handler intakes are higher than might be expected,
with a mean value of about 55 L/s per person. However,
these elevated values are not so unexpected given the
low occupant density (mean of about 4 persons per 100
m2) and the high outdoor air fractions (mean of about
35%). Air change rates based on peak carbon dioxide
concentrations in the space are lower than the
volumetric values with a mean of about 20 L/s per
person. Questions exist regarding the reliability of
these peak CO2 values based on the validity of the
assumptions on which the determinations are based.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899