Indoor air quality is both a technical and socio-economic challenge, shaping health, behaviour, and policy outcomes. Studies and pilot projects in households, schools, and industries indicate the need for practical, evidence-based interventions that reduce exposure and scale effective pollution-control measures.
Indoor air quality (IAQ) is widely considered a technical challenge, but it is equally a socio-economic issue. The work involves designing government interventions, conducting pilot studies, analysing results, and recommending how successful models can be scaled up. Several studies have been conducted on indoor air quality measurements to understand how different communities experience and respond to air pollution within their homes and institutions.
Socio-Economic Impact and Household Behaviour
People spend more than 90 percent of their time indoors—whether working in offices, cooking for long hours in kitchens, or elderly individuals resting at home. The nature of exposure varies greatly across socio-economic groups. Low-income households that rely on biomass fuels are exposed to high levels of particulate matter, while middle-income households using LPG are exposed to different gases at comparatively lower PM levels. Students in schools also face indoor air pollution due to outdoor air entering through open windows and chalk dust in classrooms, which can affect their cognitive abilities, attention span, and problem-solving skills.
A study conducted in over 3,500 Delhi households between 2018 and 2020 assessed indoor pollution levels, public awareness, and behavioural responses. Households were provided with IAQ sensors and, in some cases, air purifiers. Although PM2.5 levels were extremely high—up to 25-30 times the WHO limits—there was little behavioural change even after residents viewed real-time pollution data. Indoor pollution was often worse than outdoor levels, mainly due to poor ventilation. The research showed that awareness alone does not lead to action. To address this gap, community engagement methods such as local plays, placard campaigns, and nukkad nataks were introduced in low-income areas to create relatable and effective awareness. The impact of these methods is being further studied.
Classroom Studies and Evidence-Based Environmental Policy
Similar research is underway in Delhi schools, where indoor air quality is often compromised. Air purifiers are being installed in selected classrooms, and pollution levels are continuously monitored. By comparing classrooms with and without purifiers, the study aims to determine whether improved indoor air quality enhances students’ cognitive performance and whether informed students can influence awareness within their families and communities.
Another major initiative focuses on implementing a policy through an emissions trading scheme (ETS). Regulators often struggle to curb pollution while supporting economic growth. High outdoor pollution frequently leads to industrial shutdowns. It is causing economic loss for industries and the state. An ETS helps reduce emissions while allowing industries to continue operating. After ten years of development, the programme was successfully piloted in Surat and has since expanded across districts in Maharashtra. The scheme resulted in a 20–30 percent reduction in emissions, improved compliance, and enabled industries to generate revenue by selling unused permits. The approach emphasises the importance of piloting innovative policies, generating strong evidence, and scaling them up based on proven results.