| The present study is a study of air pollution levels inside and outside a specially designed wing of the Brookhaven Medical Center in Dallas, Texas, called the Brookhaven Environmental Control Unit where chemically sensitive patients are treated.;The Environmental Control Unit is a specially constructed and operated unit to treat patients who are hypersensitive to various chemicals in their environment. By creating an environment that is as free as possible from inhaled and ingested contaminants, the agents thought to be responsible for environmentally triggered cardiovascular diseases, including thromobophlebitis, vasculitis, arrhythmias, and other smooth muscle inflammatory diseases, can be identified.;In order to minimize indoor sources of air contaminants, the Environmental Control Unit is specially constructed and furnished with chemically low outgassing materials. The walls in various areas of the Unit are made of either porcelain, aluminum, or ceramic tile. The floors are covered with either hard vinyl or ceramic tiles, and the ceilings are either aluminum, porcelain, or made of gunite, a low outgassing plaster. Beds and furniture are made of metal or hardwood and void of volatile plastics.;Monitoring of air contaminant levels inside and outside the Unit was performed to establish relationships between indoor and outdoor air contaminant levels and to identify possible sources of indoor air contaminant levels. Measurements showed that all detectable inorganic gas contaminants except CO had contaminant levels that were higher outside than inside the Unit. Also, peak indoor levels of carbon monoxide followed peak outdoor levels with a one or two hour delay. Some organic gas concentrations such as benzene and toluene were higher indoors than outdoors, and particulate levels were highest in the lobby of the hospital.;By using a mass balance equation (Moschandreas, et al., 1978) relating changes in indoor air contaminants to changes in outdoor air contaminants, natural ventilation rates were predicted for the Environmental Control Unit. An empirical model was developed to relate natural ventilation rates to the prevailing meterological conditions. Parameter uncertainty analysis was performed on different indoor air quality models using stochastic simulation. This analysis demonstrated the accuracy of measurement necessary for each independent variable to obtain a desired accuracy for the dependent variable, indoor concentration. |
