- Author
- Persily, A. K. | Dols, W. S.
- Title
- Field Measurements of Ventilation and Ventilation Effectiveness in an Office/Library Building.
- Coporate
- National Institute of Standards and Technology, Gaithersburg, MD
- Journal
- Indoor Air, Vol. 3, 229-245, 1991
- Sponsor
- Department of Energy, Washington, DC
- Keywords
- ventilation | office buildings | libraries | carbon dioxide | air quality
- Abstract
- Mechanical ventilation system performance involves the provision of adequate amounts of outdoor air, uniform distribution of ventilation air within the occcupied space, and the maintenance of thermal comfort. Standard measurement techniques exist to evaluate thermal comfort and air change rates in mechanically ventilated buildings; procedures to evaluate air distribution or ventilation effectiveness in the field are still being developed. This paper presents measurements of air change rates and ventilation effectiveness in an office/library building in Washington, DC. The tracer gas decay techniques was used to measure whole building air change rates. The air change rates during the measurement period were essentially constant at about 0.8 air changes per hour, somewhat below the design specification and above the minimum recommended in ASHRAE Standard 62-1989. Ventilation effectiveness was investigated at several locations within the building through the measurement of local tracer gas decay rate and mean local age of air. The ventilation effectiveness measurements serve as an investigation of the applicability of the measurement procedures employed, provding insight into the measurement issue of establishing initial conditions, the spatial variation in test results a building, and the repeatability between tests. The results of the ventilation effectiveness measurements are consistent with good distribution of the outdoor air by the ventilaiton system and good mixing within the occupied space.