The indoor air quality (IAQ) of five workstations within a detergent production unit was monitored. Particulate matter (PM) was measured using a gravitational settlement method, and later characterized. To ascertain the quality of indoor air within the workstations, which could directly or indirectly affect the health and performance of the workers, a physical inspection of the plant premises was undertaken. The mean value of the following air-quality parameters; particulate matter(PM2.5), particulate matter (PM10), formaldehyde (HCHO), volatile organic compounds (VOCs), carbon dioxide (CO2), temperature (T) and percent relative humidity (%RH) were obtained within the range of 24.5-48.5 µg/m3, 26.75-61.75 µg/m3, 0.0-0.012 mg/m3, 0.09-1.35 mg/m3, 1137-1265 ppm, 25.65-28.15 °C and 20.13-23.8%, respectively. Of the particulate matter components characterized, sodium oxide (Na2O)-25.30 mg/m3, aluminum oxide (Al2O3)-22.93 mg/m3, silicon dioxide (SiO2)-34.17 mg/m3, sulfur trioxide (SO3)-41.57 mg/m3, calcium oxide (CaO)-10.94 mg/m3 and iron III oxide (Fe2O3)-19.23 mg/m3, were of significance. These results, compared with international standards for industrial indoor air quality, suggest that indoor air contamination emanating from the chemicals used in production workstations is traced to the design of the plant structures and the activities carried out within the workstations.
Keywords: characterization; detergent plant; indoor air quality; monitoring.