The determination of ambient air quality within an environmental care unit

Various chemicals found in the environment have been suspected of initiating or contributing to conditions such as asthma, dermatitis, irritability, headaches, cardiac arrhythmias, thrombophlebitis, and vasculitis. The increasing number and variety of chemicals present in the environment has led to the hypothesis that there may also be a corresponding increase in the number of people who are sensitive to these chemicals. Sensitive individuals may be continually exposed to chemical insults in their normal environment and may be experiencing a chronic reaction; however, an exposure-response relationship is difficult to establish. An Environmental Care Unit (ECU) provides an atmosphere that minimizes exposures to potential insults so patients symptoms of reaction to chemical insult may be relieved before challenge testing. Air quality required within an ECU to achieve this symptom remission is not known; therefore, this study was designed to document and compare concentrations of six criteria pollutants (sulfur dioxide, carbon monoxide, nitrogen dioxide, hydrocarbons, total suspended particular, and ozone) and formaldehyde within the ECU, the hospital outside the ECU, and the ambient atmosphere of the neighborhood around the hospital. Air movement studies indicated that the ECU was under positive pressure with respect to the rest of the hospital and had an air supply to air exhaust ratio of approximately two. Overall, no significant differences were found for any sampled pollutant at sites within the ECU or between ECU sites and the hospital proper. With an exception of ozone, significant differences among contaminant concentrations were noted between the atmosphere of the surrounding neighborhood and the hospital proper.(ABSTRACT TRUNCATED AT 250 WORDS)