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Researchers at BITS Pilani Hyderabad have developed India’s first customized Indoor Air Quality scale. Unlike conventional air purifiers that measure only particulate matter, this scale tracks all key indoor pollutants.

What is indoor air pollution?

Indoor air pollution refers to the presence of harmful substances in the air inside homes, offices, schools, or other enclosed spaces that can negatively affect human health. Unlike outdoor pollution, indoor pollution comes from sources within the building itself or from pollutants entering from outside.

Common sources include:

• Combustion sources: Cooking stoves, heaters, incense sticks, candles.
• Household chemicals: cleaning agents, paints, aerosols, and disinfectants.
• Particulate matter: Dust, construction debris, and fibers from furniture or textiles.
• Biological pollutants: Mold, bacteria, viruses, and pet dander.
• Gases and Volatile Organic Compounds: Carbon monoxide, nitrogen oxides, benzene, formaldehyde, and methane from decaying waste. 

Key Findings:

• According to World Health Organisation report, indoor air pollution is estimated to cause about 2 million premature deaths annually.
• India’s indoor average annual PM2.5 was reported around 18 µg/m³, exceeding the WHO guideline value in multiple months. (Source: World Economic Forum)
• Indoor air in India worsens during winter: It is found that 41 % dirtier overall in winter and 48 % worse in Delhi compared to outside air. Given that people spend 60‑90% of their time indoors, (Source: World Economic Forum) 

What are the broader consequences of Indoor air pollution?

• Indoor air pollution (IAP) is a major contributor to disease burden. For example, a healthy India alliance 2019 report estimates that in India, indoor air pollution accounted for 91.5 million DALYs (disability‑adjusted life‑years) globally in 2019. 

• Social equity: Poor households, rural families, and low‑income groups often use biomass, kerosene or solid fuels, live in smaller rooms with poor ventilation, and thus bear the greater burden. For example, around 660 million people in India relied on biomass for cooking/heating in 2019. (Source: Indian Council of Medical Research). 

• Indoor sources reflect broader environmental problems: Using solid fuels, poor building ventilation, poor waste management indoors point to infrastructure gaps. For instance, India has the highest average annual indoor PM2.5 (~55 µg/m³) according to one report from Dyson’s data. 

• Monitoring and regulation of indoor air quality are far behind those for outdoor air. This regulatory gap means many households aren’t aware of risks or protected by standards. 

What are the government mitigation strategies?

Pradhan Mantri Ujjwala Yojana (PMUY):

• Provides LPG connections to households using solid fuels.
• Over 80 million connections distributed since 2016.
• Reduces indoor exposure to PM2.5 and CO from biomass burning.

National Biomass Cookstoves Programme (NBCP): Promotes energy-efficient and low-emission stoves in rural areas.

Solar and electric cooking initiatives: Pilot programs under Saubhagya and State Renewable Energy Departments encourage solar-based and induction cooking.

Bureau of Indian Standards (BIS): Published standards for indoor air pollutants such as PM2.5, CO, VOCs in public buildings.

National Building Code (NBC) 2016: Encourages adequate ventilation, cross-ventilation, and air exchange rates in residential and commercial buildings. 

What are ways to reduce indoor air pollution?

• Introduce mandatory indoor air quality (IAQ) standards for all residential, commercial, and institutional buildings.
• Update National Building Code and Smart Cities guidelines to make IAQ monitoring and ventilation standards compulsory.
• Accelerate the adoption of LPG, electric, and solar cooking solutions in rural and urban households still using biomass fuels.
• Promote subsidies and incentives for energy-efficient cookstoves and induction-based cooking appliances.
• Conduct nationwide campaigns to educate people about indoor pollutants, their health risks, and mitigation measures.
• Encourage simple lifestyle changes, like improving ventilation, reducing incense burning, using low-emission cleaning agents, and segregating waste.
• Include Indoor Air Quality -related health impacts in public health programs, especially targeting women, children, and the elderly.
• Train healthcare workers to identify and advise on indoor pollution-related illnesses. 

Conclusion:

Indoor air pollution poses serious health and environmental risks, especially in densely populated and poorly ventilated spaces. While initiatives like clean cooking fuels and IAQ monitoring help, lasting improvement requires a combination of awareness, technology, proper ventilation, and policy support. 

Source: Indian Express