Assessment of Outdoor and Indoor Air Quality in Some Secondary Schools in Oyigbo Local Government Area, Rivers State, Nigeria

This study was based on seasonal assessment of outdoor and indoor levels of particulates and gases in secondary schools across Oyigbo Local Government Area in Rivers State, Nigeria. The study adopted the mixed research design. Real‐time monitors recorded size‐fractionated particulate matter (PM1, PM2.5, PM4, PM7, PM10) and gaseous pollutants (CO, NO2, SO2, VOCs, O3 over dry (Harmattan) and wet seasons. Concurrent measurements of temperature, relative humidity, wind speed, and wind direction enabled analysis of meteorological influences on pollutant dynamics. Dry‐season outdoor PM10 ranged from 131.1 – 168.2 µg/m3 with a mean of 146.27± 14.1 µg/m3 and wet‐season means ranged from 42.3 ± 24.5 to 148.8 ± 9.8 µg/m3. Indoor PM10 consistently exceeded outdoor levels, with mean indoor/outdoor ratios of 1.05–1.15 for PM2.5 Humidity correlated negatively with PM2.5 (r = –.68), and wind ‐speed increases of 1–2 m/s during the wet season enhanced pollutant dispersion. Over 80% of school sites exceeded the Nigerian NAAQS for PM10 in the dry season, underscoring urgent need for intervention. Industrial emissions and unpaved roads contributed the highest PM levels in Oyigbo, There is the ardent need to strengthen enforcement of National Ambient Air Quality Standards in school zones, with regular inspections and penalties for nearby industrial and traffic sources that exceed limits. Similarly, update zoning regulations to prevent new schools from being built near heavy‐traffic corridors, gas‐flaring sites, and industrial plants as well as prioritising relocation or mitigation for existing schools in high‐pollution areas is inevitable. Establish green buffer zone around school perimeters and playgrounds to trap windblown dust and absorb gaseous pollutants.