Photo: Narassima M S/Pexels
- Outdoor air being as foul as it is in many places in India, there is a misguided impression that indoor air is better.
- Burning wood indoors increases the concentration of PM2.5 particles. In more urban settings, asbestos, formaldehyde and volatile organic compounds dominate.
- The National Green Tribunal has ordered Union ministries to figure out a way to regulate indoor air quality in India – a significant ruling.
- Developing this framework is going to be hard – but if the ministries manage it, India can reap important public health benefits.
Kochi: The mention of “air quality” brings to mind two things: air thick with smoke and dust in the outdoors and cleaner, more filtered air indoors. This is a misunderstanding: according to one estimate, 1.3 million people die every year in India due to indoor air pollution.
Poor air circulation indoors increases the concentration of harmful particulate matter and can help transmit airborne diseases.
In an important ruling on April 19, the National Green Tribunal directed the Union government to develop a framework to regulate indoor air quality in public places (like movie halls and markets) in four months. This is a vital first step – if the government can figure out how to measure indoor air quality properly.
Ignored yet vital
Indoor air quality is as grave a health concern as outdoor air quality. It affects women and children disproportionately more, especially in households that burn firewood for cooking.
Burning wood indoors increases the concentration of PM2.5 particles. In more urban settings, like office buildings, asbestos and gaseous pollutants like formaldehyde and volatile organic compounds, released from compounds like paints, are among the common sources of air pollution.
Poor ventilation – such as inefficient air-filtering that recirculates the air from inside – can also spread infectious diseases.
There are several guidelines pertaining to indoor air quality. The WHO has guidelines for indoor air quality – so has the Council of Scientific and Industrial Research at the national level in India. In 2021, the latter published new guidelines on ventilation inside residential and office buildings in light of COVID-19, also an airborne disease. It was updated in 2022.
The similar ‘Green Rating for Integrated Habitat Assessment’ guidelines, originally developed by The Energy Research Institute (TERI), Delhi, rates buildings based on indoor air quality, among other parameters.
The problem is that guidelines can’t really be enforced like laws, Raja Singh, a visiting faculty member and research scholar at the School of Planning and Architecture, New Delhi, told The Wire Science.
“And from what I have researched on this, India does not have [a law] pertaining to indoor air quality.”
It’s an order
This could change if the Union environment ministry and the Central Pollution Control Board (CPCB) implement the NGT’s latest order – to develop a framework to regulate indoor air quality.
On April 19, the NGT took into consideration two cases pertaining to this matter. The first was filed in 2016 and highlighted the health effects of indoor air pollution. At the time, the tribunal recommended that the environment ministry prepare standards for indoor air quality and ordered it to file a progress report in 2018.
This report has not seen the light of day, the NGT said this time.
The second case, which Singh filed in 2021, discussed why good indoor air quality is vital with regard to the spread of infectious diseases.
The NGT finally ruled that the government was required to regulate indoor air quality in public places under the Air (Prevention and Control of Pollution) Act 1981 or the Environment Protection Act or Rules 1986. It ordered the Union environment ministry and the CPCB, together with the ministries of urban affairs and health, to develop a framework in four months.
Once the regulation is in place, we can finally say that it is legal to have standards for indoor air quality of public spaces, Singh told The Wire Science.
“It is a new field,” Singh said of indoor air quality. “Only in the past four decades have we seen a shift in the time we spend indoors and the activities we do in closed spaces. With time, the law has to recognise new things”.
The path to this law may be a twisted one, however. Regulating indoor air quality is “very important” but developing a framework will be challenging, R. Suresh, a senior fellow and area convenor of the Centre for Environment Studies in TERI, said.
One issue is the big differences between indoor air quality across rural and urban areas. Even pollutants vary. While particulate matter and carbon monoxide are the major pollutants in rural areas, volatile organic compounds and formaldehyde dominate in urban indoor settings, Suresh said.
So an indoor air law will have to treat rural and urban areas differently.
Second, there are no protocols to monitor indoor air quality – and collecting data on it will require different methods than those used for the protocols already in place vis-à-vis outdoor air. Ventilation will need to be taken into account as well.
Healthy building, healthy tenants
All this said, regulating indoor air quality is crucial, according to Singh, because public-and-closed spaces include hospitals – and other buildings that can help manage diseases.
“India has to eradicate tuberculosis by 2025, the prime minister said on stage,” Singh recalled. “To get there, it has to be a multi-sectoral effort, not only spearheaded by doctors but by every other profession contributing to it, such as architects, environmentalists and public health experts.”
Hospitals in India also have a major problem in the form of healthcare-associated infections (HAI). As Priyanka Pulla reported in 2020, “When patients contract an infection after being admitted to a hospital, they are said to have” an HAI.
The National Accreditation Board for Hospitals and Healthcare Providers has a stringent checklist for hospitals aspiring to eliminate HAIs. A law to control indoor air pollution can help enforce these measures and prevent the spread of infectious diseases in other settings, potentially easing stress on the healthcare system.
For example, one of the most cost-effective ways to achieve this is dilution ventilation, Singh said. It is simply using an air-conditioning system to dilute indoor air by constantly pumping in air from the outside.