Design and performance of a system to control concentrations of common gaseous air pollutants within environmental laboratories used for human exposure studies
Titel:
Design and performance of a system to control concentrations of common gaseous air pollutants within environmental laboratories used for human exposure studies
Auteur:
Glover, Donald E. Berntsen, Jon H. Crider, Walter L. Strong, Arthur A.
Verschenen in:
Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering
Paginering:
Jaargang 16 (1981) nr. 5 pagina's 501-522
Jaar:
1981
Inhoud:
One area of responsibility of the Environmental Protection Agency (EPA) is to determine the effects of air pollution exposure on human health. To generate carefully controlled pollutant exposure conditions and to determine their effects on the human body, EPA has established a Controlled Environmental Laboratory (CEL) where all exposure, stress and body function parameters are carefully controlled and documented. The design and performance of the pollutant gas control system for the CEL is described. This system allows human test subjects to be exposed to constant or varying concentrations (equivalent to ambient levels) of SO2, NO, CO, NO2 and O3. The pollutant gas control system uses closed loop feedback control to obtain a control error of less than ±5% or twice the lower detection limit of the analyzer, whichever is greater. Status of all critical system components is constantly monitored and stored on magnetic tape to ensure subject safety and to provide for offline data validation.