A field study on determination of carbon monoxide level and thermal environment in an underground car park

Results of a field study to investigate traffic pattern, carbon monoxide (CO) level and thermal environment are presented. The experiment was conducted over a period of 6 days in a medium size commercial underground car park. First, traffic volume, hourly engine operation time and parking lot occupancy level were measured. A correlation between the hourly engine operating time and traffic volume is obtained. CO and temperature levels were then measured in selected locations. Hourly average CO concentration is correlated with engine operating time fraction, effect of ventilation system (historic effect). For thermal environment, hourly average temperature is correlated with engine operating time fraction, ambient temperature, and historic effect. Both correlations are achieved with the R 2 value exceeding 90%. The study provides quantitative information for modelling. It is also directly useful in design of mechanical ventilation system at similar underground car parks. (C) 2003 Elsevier Ltd. All rights reserved.