Indians cannot ignore indoor air quality crisis

This article is authored by P GopalaKrishnan, managing director, Southeast Asia and Middle East, GBCI.

India is now living through a prolonged air quality crisis that goes far beyond the winter smog seen in northern cities. A recent nationwide analysis found that 60% of the country’s districts experienced polluted air throughout the year. Not a single district met the World Health Organization’s guideline for annual PM2.5 (fine particulate matter that is less than 2.5 microns in diameter). Even against India’s own, more lenient threshold, only 40% of districts remained within the safe range.

Boost indoor air quality to combat poor AQI conditions.

This changes the conversation entirely. Pollution is no longer a seasonal disruption that can be managed through temporary restrictions and emergency measures. It is a constant environmental condition affecting how people live, learn and work. And it has direct implications for how buildings perform.

Outdoor particulate matter enters indoor environments through infiltration, mechanical systems, poorly sealed envelopes and routine air exchanges. Even in modern buildings, indoor PM2.5 levels often track outdoor trends with only a slight delay. When outdoor air remains polluted for weeks at a time, indoor air quality (IAQ) will inevitably deteriorate unless the building has been consciously designed and operated to counter this.

For a country where people spend most of their time indoors, this means one thing. Indoor air quality must become a year-round public health priority.

While the scale of the problem is national, the solutions begin inside individual buildings. Offices, schools, hospitals, commercial spaces, and residential developments all can reduce exposure, regardless of their location.

The first step is to strengthen filtration. Many Indian buildings still use filters that only trap large particles, which offer little protection against PM2.5. High-efficiency filters that are compatible with existing HVAC systems can make an immediate difference. Selection must go beyond the rating printed on the label. Media characteristics, pressure drop and dust-holding capacity significantly influence performance.

The second step is smart ventilation. Buildings need fresh air, but during periods of high outdoor pollution, that fresh air must be filtered. Systems must be tuned so that intake air is managed thoughtfully and recirculation is optimised. This becomes especially important in regions where pollution peaks quickly after monsoons or during dry summer months.

The third is continuous measurement. Indoor air quality cannot be improved if it is not tracked. Basic monitoring of particulate matter, CO2 and humidity enables facility teams to adjust operations in real time. This helps buildings remain resilient even when outdoor conditions worsen unexpectedly.

Finally, routine maintenance is non-negotiable. Filters need to be cleaned or replaced according to manufacturer guidance. HVAC systems should be checked for leaks, blockages or inefficiencies. In a high-pollution country, maintenance is not just operational discipline, it is a health measure.

To understand how filtration technologies actually perform under Indian pollution conditions, GBCI India conducted a five-month field study in Noida with Hollingsworth and Vose. The project monitored three MERV 14 (Minimum Efficiency Reporting Values) filters across identical spaces. Each filter had the same rating, yet their performance differed substantially.

The filter using advanced electret media demonstrated a clear performance advantage. It maintained indoor PM2.5 levels within healthy limits even on days when outdoor pollution spiked sharply. It also required less fan power, reducing HVAC energy consumption by 29%. This combination is significant. It proves that better filtration and energy optimisation are not competing objectives.

One of the most important lessons from the study is that filter ratings alone do not tell the full story. Two filters with the same MERV rating can behave very differently depending on the media used. For India’s commercial real estate owners, hospitals, educational institutions and public buildings, this insight matters. It can guide more informed procurement and operational decisions, particularly in regions that see long periods of high pollution.

This field study complements another GBCI research effort, conducted with Saint-Gobain Research India, which assessed the indoor environment in 30 Indian workplaces. The study showed widespread gaps in air quality, lighting, noise and ventilation, even in better-designed buildings. The key takeaway was clear. Healthy building performance requires continuous operation and maintenance, not just good design.

Together, these studies show that India has both a performance gap and an opportunity. With the right filtration, monitoring and maintenance strategies, indoor environments can remain healthy even when outdoor air is not.

With 60% of districts experiencing year-round polluted air, India cannot rely solely on external measures to protect public health. Buildings must serve as active protective environments. They are where students learn, employees work, patients recover and families spend most of their time. Their ability to shield occupants from outdoor pollution is central to national resilience.

This requires three mindsets:

• First, healthy air must be viewed as essential infrastructure. High-performance filters, well-tuned ventilation, and monitoring systems should be treated with the same seriousness as fire safety, electrical reliability and structural integrity.
• Second, buildings must be prepared to respond dynamically to environmental volatility. When pollution spikes rapidly, buildings should be able to switch modes, reduce intake of unfiltered air and maintain safe indoor conditions until outdoor levels improve.
• Third, healthy building practices must become mainstream, not a niche. Green certification programs such as LEED (Leadership in Energy and Environmental Design) have long emphasised indoor air quality. India’s challenge now is to scale these principles across conventional buildings, as well.

India’s building sector also has a clear roadmap for this shift. The latest version of the LEED rating system, LEED v5 launched earlier this year, places stronger emphasis on verified indoor environmental performance. The new framework strengthens the focus on human health through clearer requirements for ventilation, filtration, pollutant source control and continuous monitoring, supported by greater transparency and accountability around actual building performance.

Projects are now required to demonstrate how systems perform during real operations, not just on paper. LEED v5’s quality-of-life credits also place occupant health, comfort and well-being at the centre of building strategies.

This shift is significant. It recognises that buildings must remain resilient to environmental volatility while ensuring healthier indoor environments every day. As India confronts sustained outdoor pollution, LEED v5 offers building owners a practical, globally benchmarked framework to close the gap between design, operation and actual IAQ performance on the ground.

Healthy buildings are not an optional upgrade. They are a public health tool.

The data from national studies and GBCI’s field research converge on a single conclusion. Indoor environmental strategies must be strengthened across India if we want to meaningfully reduce exposure. Outdoor air quality will take time to improve. Indoor air quality, however, can be improved today.

This article is authored by P GopalaKrishnan, managing director, Southeast Asia and Middle East, GBCI.