How do we address Indoor Air Quality in City Level Air Quality Action Plans?


Ministry of Environment, Forests and Climate Change (MoEF&CC) in India launched National Cleaner Air Programme (NCAP). The NCAP is a mid-term, five-year action plan that includes collaborative, multi-scale and cross-sectoral coordination between relevant Central ministries, State governments and local bodies. The objectives of the plan align with existing policies and programs, including the National Action Plan on Climate Change, initiatives on electric vehicles, the Smart Cities Mission among others.

A budget amounting to Rs 6370 million has been set aside for aiding implementation of the programme. A budget of Rs 3000 million has been allocated for two years to tackle air pollution across 102 cities, that have been identified by the Central Pollution Control Board (CPCB) who do not meet the ambient air quality standards. See the outline of NCAP as depicted below. It may be observed that Preparation of Guidelines on Indoor Air Pollution has been included in the NCAP. But are the guidelines just enough?

Outline of National Clean Air Programme 

Several cities have prepared city level air quality action plans and the approved action plans have been posted on the CPCB website.

These action plans essentially address the challenges to combat “outdoor” or ambient air pollution. None of the action plans address indoor air quality.

We all know that when it comes to the public health, indoor air quality plays an important or perhaps even a dominant role. The action plan needs to address both outdoor and indoor air quality i.e. the plan should be based on an integrated strategy. Afterall, the purpose of preparing clean air quality action plans is to protect the public health. The objective of meeting the ambient air quality standards is only a step in this direction based on a pre-cautionary approach. Mere attainment of outdoor or ambient air quality standards is not assuring or good enough.  The question is how to do build such integrated city level air quality action plans.

But first, we have several questions and challenges to address.

We don’t know where we are, and we don’t know where do we want to go.

For any action plan, one needs to have baseline data and the standards that we want to achieve. On ambient air quality, we have some baseline data (although not necessarily sufficient and reliable) and we have ambient air quality standards prescribed by CPCB. When it comes to indoor air quality, we have neither the baseline data nor the indoor air quality standards.  So, we really don’t know where we are, and we don’t know where we want to go! Remember that limitation is not just the absence of indoor air quality standards, but we require a monitoring protocol for indoor air quality and training given on how to. If not done, we will be confronted with a lot of garbage data.

Are Outdoor and Indoor Air Quality Correlated?

There have been numerous studies that show that there is no definitive correlation between indoor and outdoor air quality. Correlations depend on the extent of air exchange, indoor emissions and air circulation inside the house apart from the outdoor air quality. Further, relationships depend on the parameter e.g. correlations are poor for Volatile Organic Compounds (VOCs). So, improving ambient air quality does not necessarily imply a similar improvement in indoor air.

What should be the response strategy? Via Monitoring and Enforcement by Pollution Control Boards or by advocating Normative or Prescriptive Standards?

Given this situation, strategies to manage indoor quality will be to ensure better design of the built structures, reducing of indoor air emissions and installing adequate air circulation and air cleaning systems. You can regulate the above by indoor air quality sensitive architectural and building standards, recommend and discourage certain high VOC emitting materials and install proper air circulation and cleaning systems.

Will this require approval, inspection and monitoring by a State Pollution Control Board? Certainly, this will not be possible and nor practical. For large public places such as theaters, convention centres and sensitive locations such as hospitals, we may ask for a certification on Indoor Air Quality that may state that the place is safe to breath. Commercial complexes like IT parks where the buildings host thousands of professionals, such a certification may be made mandatory. The questions will be what should be the certification criteria, how will the fitness of the built structure for safe indoor air quality be checked, who should be the assessors and certifiers? What will be the certification renewal strategy? and what will be the associated costs etc. In all the places where such a certificate will be asked, it may be made mandatory to put a real time display of indoor air quality covering key parameters like VOCs, Carbon Dioxide and PM2.5 , apart from temperature and humidity.


So how should then the integrated air quality action plan be built? The plan will need some assessment of baseline situation, both ambient and indoor and then identification of prioritized interventions with roles and responsibilities.

For outdoor or ambient air quality, we may look at how to achieve a modal shift to public transport, curb open burning of wastes and industrial emissions, reduce resuspension of road dust, promote cleaner fuels etc. On indoor air quality focus could be enclosed public places (like cinema halls, convention centers), underground metros, schools and hospitals and large commercial complexes. Baseline surveys will have to be done to capture relevant metadata, especially on the potential indoor emissions and on prevalent respiratory illnesses of the occupants. This kind of monitoring will need to get institutionalized to ensure regular upkeep and tracking, something the city administration and pollution control boards are not experienced to do today. We will need to get some of the academic and research institutions involved. That can well be a challenge as we need to do capacity building of these institutions in Indoor air and raise financial resources. The State PCBs who hold substantial funds could fund and agencies like CPCB could provide technical guidance. Organizations like Society for Indoor Environment (SIE) that operate in India can certainly help with its various regional chapters.

Concurrently, we need to evolve national guidelines using NCAP’s budget (cited earlier) focusing on indoor air quality. These guidelines should be for architects and builders, interior designers and HVAC system makers. Citizen awareness on indoor air emissions is going to be very important for both mechanically ventilated and naturally ventilated built structures. Information, Education and Communication (IEC) related efforts on this subject should be a part of the city level air quality action plans. Awareness and action could be rather challenging for situations such as congested housing (sometimes called as affordable!) and poorly ventilated slums where dirty fuels are used.

The city level clean action plans may start with indoor air quality certifications as earlier described. Indoor air quality in enclosed public places could be the priority. Such a certification scheme will require a good coordination with all the key stakeholders such as architects and builders, interior designers, HVAC system makers, material suppliers, realty developers and investors, medical doctors, research and academia. The certification schemes will have to established at the national level under NCAP. Each city in their air quality action plans could then come up with its adoption, a roll out plan, listing the “hot spots” and explain how the certification scheme will operate. Let us also know progress on certifications and the impact.

If a cinema hall for instance obtains a certificate on Indoor Air Quality, then it may proudly display on its signage and even print at the backside of the ticket as “Here you can breathe safe”. Surely, such a  communication will make this Cinema Hall as the preferred theater by the patrons and people won’t mind even paying 10 Rs extra for that assured safety.

To sum up, we need to recognize indoor air quality as an important element in our city level air quality action plans. The approved action plans posted on CPCB’s web site today do not address indoor air quality. Let us conduct pilots to demonstrate how to integrate outdoor and indoor air quality, at least in few priority cities as models for other cities to follow.

We need to peep inside the box and not just watch the box from outside!

Sometimes, thinking out of the box may not always work!!

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  1. Prof. Modak, is there any standard protocols and parameters for indoor air quality baseline monitoring?

  2. Creating awarenesshas to be priority. Presently,indoor implies only residential – kitchens and drawing rooms of apartments and rural habitats. Theatres, meeting rooms , shopping complexes, etc. have to prioritised. In their early days, SOCLEEN had surveyed cloth markets and a municipal school in south Mumbai, and expressed serious concern about respiratory health of sales staff in market and children in school. The latter received corrective response from related authorities.
    Prof. Sharad Chaphekar.

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