Investigation on the ambient air quality in a hospital environment

This study examined the ambient levels of criteria air pollutants in the indoor and outdoor environment of a typical hospital facility. Ambient concentration of the criteria pollutants was monitored at nine sampling locations using the ToxiRAE gas monitors both in the rainy and dry seasons. The results showed that the overall 24-h concentrations for CO and NH 3 were 0.18 ± 0.19 and 0.11 ± 0.13 ppm, respectively, for dry season. During the wet season, the extrapolated 24-h concentrations ranged 0.09-1.09 ppm for CO, 0.04 ± 0.08 ppm for NH 3 while NO and NO 2 had 0.03-0.21 ppm and 0-0.06 ppm, respectively. The result of the study shows that the 24-h NH 3 concentration of 0.44 ppm recorded at S5 during dry season breached the National Air Quality Standards of the Federal Ministry of Environment Standard, Nigeria. Similarly, NO and NO 2 levels were higher than other gaseous parameters measured in all the sampling locations during the wet season. This study establishes that human activities may have deleterious effect on air quality in the hospital airshed.