Assessment of Indoor Particulate Matter and Teacher's Perceived Indoor Climate in Government Schools of Bilaspur District, Chhattisgarh, India: A Cross-Sectional Study.

Context: Indoor air pollution (IAP) affects the long-term health, cognitive growth, and academic performance of children. Since children spend most of their time at school, quantifying IAP in classrooms is an important parameter for air pollution.

Aim: To assess the average particulate matter (PM) levels inside and outside of classrooms along with their associated factors and teacher's perceived indoor climate.

Setting and design: Cross-sectional survey in nine government-run schools.

Methods and material: PM_2.5 and PM₁₀ were measured inside the classroom and outdoors simultaneously during summers, using an Atmos monitor for two consecutive days, along with several school and classroom characteristics. Perception about indoor air quality was captured from teachers (n = 15) using a validated questionnaire.

Statistical analysis: Mean values of PM using mixed effect linear regression. Perceived indoor air quality is presented using percentages.

Results: Mean indoor PM_2.5 and PM₁₀ was 52.5 µg/m³ and 65 µg/m³. Indoor and outdoor PM levels were highly correlated, but the indoor-outdoor ratio of PM concentrations was more than 1. Teachers were mostly bothered by dust, dirt, and noise in the schools.

Conclusion: Indoor air quality was higher than World Health Organization (WHO) standards but within the national standards. Need further research to find the exact cause for higher indoor PM levels compared to outdoor PM levels.