Air change rates and carbon dioxide concentrations in a high-rise office building

Conference · Sat Dec 31 04:00:00 EST 1994

OSTI ID:33325

Reardon, J T; Shaw, C Y ^[1]; Vaculik, F ^[2]

---

1. National Research Council of Canada, Ottawa, Ontario (Canada). Inst. for Research in Construction
2. Public Works Canada, Ottawa, Ontario (Canada). Building Performance Division

The feasibility of controlling ventilation rates using occupant-generated carbon dioxide (CO{sub 2}) as the control index has been examined in a large high-rise office building with a constant-volume heating, ventilating, and air-conditioning (HVAC) system. Daily CO{sub 2} concentration profiles throughout the building and air change rates, using sulfur hexafluoride (SF6) as a tracer gas, were measured for several outdoor air supply rates. Of particular interest was how well the CO{sub 2} concentrations measured in the central ventilation system`s return air plenum represented the average CO{sub 2} concentration behavior in the building as a whole. CO{sub 2} concentration profiles were also measured on individual floorspaces in the building to determine the range of variability in the concentration behavior in occupied zones. The influence of fresh air supply rates on the speed of mixing of the tracer gas (surrogate contaminant) was also examined. The practicability of using CO{sub 2} as an active tracer gas to measure air change rates was also investigated. The results are discussed in the paper.

• OSTI ID: 33325
• Report Number(s): CONF-9406105--
• Country of Publication: United States
• Language: English

Related Subjects

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
AIR FLOW
CARBON DIOXIDE
FLOW RATE
INDOOR AIR POLLUTION
OFFICE BUILDINGS
VENTILATION