Indoor air is considered safe by many. When outdoors, we encounter pollution from vehicles and industries and these emissions worry us. No wonder, the statistics reported on air quality are generally on outdoor air or ambient air. Standards for ambient air quality have been set in countries around the world and so also in India.
In some cities in India, ambient air quality is displayed on panels that are connected to real time automatic air quality monitoring stations. These displays provide us information on the air we breathe when outside – albeit in approximation. I say ’approximation’ because ambient air quality is monitored only at a monitoring station and one station does not represent the area-wide ambient air quality. Further, we are subjected to pedestrian exposure when we walk on the streets – and that’s different from the ambient air quality.
Talking about exposure, we tend to believe that staying indoors shields us from outdoor air pollution. We feel safe in enclosed spaces like offices, homes, malls and theatres, air conditioned cars, buses and railway coaches. Unfortunately, the situation is to the contrary. Indoor Air Quality (IAQ) can be just as bad as or even worse than ambient or outdoor air quality.
There are a number of reasons why IAQ can be of concern. Emissions emanate from cooking, cigarette smoking, burning of scented sticks (agarbattis) and mosquito repellent
coils, paint on the wall, seals from furniture, coatings from fabrics and carpets – releasing complex pollutants. The pollutants released include Particulates, Formaldehyde (HCHO), Radon, Tolune, Ammonia, Benzene, 2-furaldehyde, Benzyl alcohol, Monocyclic monoterpenes, Dichloromethane, Ethylhexyl phthalate, just to name a few. Most of these “micro-pollutants” are carcinogenic and difficult as well as expensive to monitor. Many times, naturally ventilated buildings are designed poorly and buildings with forced ventilation or enclosed with air conditioners, do not maintain adequate ventilation or cycles of air exchange. As a result, the micropollutants that are released indoors get accumulated – sometimes overshooting the acceptable values.
Acceptable IAQ is defined by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) in ANSI/ASHRAE standard 62.1 as: “Air in which there are no known contaminants at harmful concentrations and with which a substantial majority (usually 80%) of the people exposed do not express dissatisfaction”
Traditionally, IAQ has been associated with Sick Building Syndrome (SBS). The World Health Organization (WHO) compiled common reported symptoms into what was defined as SBS. These symptoms included: eye, nose, and throat irritation; sensation of dry mucous membranes; dry, itching, and red skin; headaches and mental fatigue; high frequency of airway infections and cough; hoarseness and wheezing; nausea and dizziness; and unspecific hypersensitivity. Most of us are facing these problems today and frequently
so. We have to keep visiting doctors and chemists.
India does not have IAQ standards. Research on IAQ in India has also been limited. Spot studies in 2005 showed high values of CO2 in auditoriums in Vadodara crossing three times the IAQ standard. I shudder to think what air we must be breathing when travelling in overnight AC buses or coaches on the train. Inside slum shanties where ventilation is poor and fuel such as wood and cow dung is used, the pollution levels have been found to be very high, leading to severe respiratory ailments, especially in women and children.
China set standards for IAQ as early as 1976. Korea has IAQ standards even for metro buses! IAQ standards in Japan and Germany cover most of the micro-pollutants listed above. It is a pity that in India we haven’t taken IAQ seriously.
But is just setting of IAQ standards going to be enough. How can we enforce such standards?
The approach will have to be multipronged, focusing on prevention and control. We will need to bring key stakeholders such as architects, paint manufacturers, furniture makers,
HVAC manufacturers, green building rating agencies, medical professionals etc. together. A combination of control, reduction (modification) with standards/guidelines may work. See Figure below.
I had organized stakeholder workshops on IAQ in Mumbai and Delhi a few years ago and tried lobbying for IAQ standards and a multi-pronged approach. I, in fact, developed a Roadmap for IAQ in India and presented it in these workshops. There was significant support and interest to follow up but we couldn’t succeed much.
There is a need to form a National Association on Indoor Air Quality in India and take on this issue with the Ministry of Environment & Forests on a collective basis. Till then, maybe it’s a good idea to wear oxygen masks, whenever indoors! It’s our choice to make – oxygen masks or the Sick Building Syndrome.
Sir, Being allergic, I’ve often been at the receiving end of liquid mosquito repellents!! Mosquitoes are driven away but I end up with a sneezing bout followed by heavy nasal congestion!! On a serious note, few simple measures (eg. provision of ceiling fans, opening doors, windows in the morning when office stars etc.) to maintain “breathable” indoor air quality could go a long way in solving many of these issues.
Have been suffering from an indoor air quality issue which I need to resolve.Would welcome any help on this.
I would be interesting and useful if you present what practical measures were suggested for IAC, for general public.
Dr Modak, Congrats for this wonderful initiative.. What is your view on using flyash bricks for houses. Do they cause indoor pollution eg radon, radiation. Should we promot use of flyash bricks for housing construction or not?
Thanks for your details and explanations..I want more information from your side..I Am working in Aquafina Mineral Water In Chennai.