With input from Dr Monica Vasudev

1136: Round Table - Expert Group on Environment Zoom Meeting on “Indoor Air Pollution - Part I”

25th October, 2020, 12 noon-1pm

Participants: Dr KK Aggarwal, Padma Shri Awardee and President, Heart Care Foundation of India. Prof Meenakshi Dhote, Dept. of Environmental Planning, School of Planning and Architecture, Delhi. Dr SK Tyagi, Ex- Additional Director, Central Pollution Control Board. Dr Dipankar Saha, Ex- I/C Air Pollution Laboratory, Central Pollution Control Board. Sh Pradeep Khandelwal, Chief Engineer, East Delhi Municipal Corporation. Sh SA Verma, General Manager (Environment), Delhi Metro Rail Corporation. Dr M Dwarkanath, Ex- Member Secretary, Puducherry Pollution Control Committee and Ex- Senior Scientific Officer, Department of Environment, Govt. of Delhi. Dr Anil Kumar, Ex- Director, Dept. of Environment, Govt. of Delhi and Director, Heart Care Foundation of India. Dr S Sharma, Editor IJCP Group

Key points from the discussion 

The meeting was chaired by Dr SK Tyagi.

• Work from home has increased exposure to indoor air pollution. People themselves increase level of carbon dioxide; also NOx, SOx, VOCs. VOCs are invisible pollutants and emanate from fuel, home appliances, air spray, personal care products, carpets, varnish and paints. Some of the VOCs are formaldehyde (carcinogenic), benzene, toluene, xylenes.
• Sanitizers are now being used because of COVID, which contain alcohol. Ethyl alcohol is less harmful than methanol. But, sometimes hand sanitizers may be adulterated with methanol.
• To prevent indoor air pollution, maintain ventilation of house, unidirectionally open; keep air-purifying plants such as Tulsi, aloe, snake plant, spider plant, palm to help control pollution.
• Risk factors for indoor air pollution: In low income group, low quality of built form has been directly correlated with level of pollution. The aspects of built form that have impact on pollution are age of building, building material used, paint used, housing typology, ventilation, fuel used for cooking and lighting, and dampness in the house.
• If there is a build-up of pollution, ventilation becomes very important.
• For industry buildings, the National Building Code 2016 has come out with ventilation standards. Depending on the building typology, they have fixed certain number of air exchanges. The HVAC parameters as specified in the Code have to be adhered to before a building is approved.
• If we want to have good air exchanges, then we have to follow those norms in terms of orientation of the building, orientation of openings and in terms of air changes. If no natural ventilation, then the air changes have to be maintained mechanically. Without ventilation, the pollution is trapped inside.
• COVID-19 may get aggravated with increased indoor air pollution.
• A study where health data from hospitals is correlated with built form may help improve air pollution.
• Source segregation has been started along with decentralization of waste management; remediation of existing landfills has been started.
• Indoor air quality in public transit, especially when there are underground stations, is a very critical issue.
• There are no standards yet for air quality in public transit.
• Type of filter used in metro is EU3 filter (G3 category); this is the most recent filter class for a saloon (coach). It will filter out particles of size 3µ or less.
• Real time monitoring of CO2, PM10 and PM2.5 at stations is done. There are no standards yet regarding what should be done if PM is increased. This is a challenge. But, if CO2 is >600pbm, then fresh air fans start running automatically in half mode; if >1000, these fans operate in full mode.
• Stations are green buildings and conform to the specifications of the Indian Green Building Council. Formaldehyde, VOCs are monitored, FAC wood is used, fixtures and fittings do not emit formaldehyde, lead free paints are used. All these may have cumulative effect.
• Always check air fresheners for methanol. Fragrance in air fresheners is only 1-2%; the rest is ethanol. Methanol, instead of ethyl alcohol is being used by some, which is harmful. 

Dr KK Aggarwal

President CMAAO, HCFI and Past National President IMA