Indoor Air Quality and Microclimatic conditions in selected Restaurants and Kitchens at a Tertiary Institution in Benin City, Nigeria

Abstract

This study investigated the levels of selected indoor air pollutant concentrations and microclimatic conditions in restaurants and kitchens at a tertiary institution in Benin City using standard procedures. Ten (10) restaurants and kitchens were randomly selected within the University environment. Indoor particulates (PM_1.0, PM_2.5 and PM₁₀), Carbon monoxide (CO), Relative humidity (RH), Temperature (Temp) and Wind speed (WS) were measured using Handheld Portable Air Samplers. The results showed that the indoor meteorological and air quality parameters ranged between 34.8 - 35.8°C and 34.5 - 35.9°C (Temp); 42.8 -70.2% and 39.7 - 66.9 (RH); 1.1 - 2.0 m/s and 1.2 - 1.8 m/s (WS); 0.0 - 25.4 and 0.0 - 28.7 mg/m³ (CO); 28.9 - 42.4 µg/m³ and 24.4 µg/m³ - 30.6 (PM_1.0); 47.0 - 75. µg/m³ and 37.4 - 50.3 µg/m³ (PM_2.5); 62.3 - 91.0 µg/m³ and 53.6 - 56.8 µg/m³ (PM₁₀) within the restaurants and kitchens respectively. The mean concentrations of the CO and particulates were above the recommended regulatory limits of the WHO in all sampling sites. There were generally weak significant associations between the observed meteorological parameters and the indoor air pollutants (R= -0.352, - 0.419 p<0.001), except for CO and indoor temperature in the kitchens (R=0.649, R² = 0.429 p<0.001). The Air Quality Index (AQI) status of the sampled sites varied from moderate to unhealthy. This study underscores the need for adequate ventilation in the sampled restaurants and kitchens and the creation of awareness of the health risks associated with indoor air pollutants in the study area.