Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Analysis of Ventilation Data from the U.S. Environmental Protection Agency Building Assessment Survey and Evaluation (BASE) Study. (NIST IR 7145) [SUPERSEDED BY NIST IR 7145-R, Published 3/10/2009]

Published

Author(s)

Andrew K. Persily, J Gorfain

Abstract

The U.S. Environmental Protection Agency (EPA) Building Assessment Survey and Evaluation (BASE) study included a range of measurements in 100 randomly selected U.S. office buildings for the purpose of characterizing the existing building stock with respect to determinants of indoor air quality and occupant perceptions of indoor environments. One aspect of the evaluation was the characterization of the ventilation systems serving the study spaces and selected measurements of ventilation performance. This report presents an analysis of these data with a focus on supply and outdoor airflow rates, including comparisons of the measured data with design values and the outdoor air requirements in ASHRAE Standard 62-2001. The results indicate that, as expected based on thermal load considerations, the average value of the design and measured supply airflow are both about 5 L/s m2 (1 cfm/ft2). The measured outdoor air ventilation is higher than might be expected, with a mean value of 56 L/s (119 cfm) per person. These rates are high on average relative to the minimum outdoor air requirements in Standard 62 due to the high outdoor air fractions (relative to minimum) and the actual occupancy being lower relative to the design occupancy. Nevertheless, about 16 % of the ventilation measurements are still below the 10 L/s (20 cfm) per person requirement in Standard 62. In addition to presenting the results of the ventilation assessments in the BASE buildings, this report contains a number of suggestions for modifications to the protocol used in these assessments.
Citation
NIST Interagency/Internal Report (NISTIR) - 7145
Report Number
7145

Keywords

carbon dioxide, design, measurement, mechanical ventilation, office buildings, ventilation

Citation

Persily, A. and Gorfain, J. (2004), Analysis of Ventilation Data from the U.S. Environmental Protection Agency Building Assessment Survey and Evaluation (BASE) Study. (NIST IR 7145) [SUPERSEDED BY NIST IR 7145-R, Published 3/10/2009], NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.IR.7145 (Accessed December 6, 2021)
Created December 1, 2004, Updated November 10, 2018