Clean Air \"Be a part of the Solution\"


Guidance Framework

Is a Framework prepared through a series of consultations by the United Nations Environment Programme (UNEP) and Clean Air Asia was developed to provide guidance in implementing the long-term vision for urban air quality in Asia.

A. Air Action Plan

  • Chennai Air Action Plan

Chennai City has not prepared any Air Action Plan, because it is not listed as a non-attainment city.

B. Monitoring Network of the city

There are 8 ambient air quality monitoring stations in Chennai City funded by the Central Pollution Control Board under the National Air Quality Management Program (NAMP). The stations are in industrial, commercial, and residential areas.

The stations are in the following area:

  1. Kathivakkam
  2. Manali
  3. Thiruvottiyur
  4. Kilpauk
  5. Thiyagaraya Nagar
  6. Nungambakkam
  7. Anna Nagar
  8. Adyar


The stations function on 24-hour basis, twice a week. The samples are collected from NMAP stations and are analysed for the Respirable Suspended Particulate Matter (RSPM) (RSPM is particulate matter less than 10 microns) and gaseous pollutants such as Sulphur di oxide (SO2) and Nitrogen di Oxides (NO2).

The data is available on the Tamil Nadu Pollution Control Board Website.

The Tamil Nadu Pollution Control Board also has a special monitoring data during the festival of Bhogi Pongal., which is available on their website.

C. Government Policies, Acts, Laws, Press Release – Central Act and Policies, State Acts and Policies. Press Release on steps which will have impact on Air Pollution.

A. Source Apportionment Study 

  • Air Quality Monitoring, Emission Inventory and Source Apportionment Study for Chennai, Chemical Engineering Department, IIT Madras


  • Characterisation of PM10­ and PM5 Emission sources at Chennai, India, Nature Environment and Pollution Technology, 2019 – Jithin Jose, B. Srimuruganandam, and S.M. Shiva Nagendra

This paper discusses the precise characteristics of PM in each locale depend on the source origin, which in turn is a function of economic, social and technological factors. In order to effectively manage PM and thereby, the exposure risk to humans, it is very essential to identify the main sources and their contributions from source emissions. Four sources were identified for both PM10 and PM2.5. Vehicular pollution (11%), crustal source (27%), marine aerosol (40%) and industrial source (22%) are the sources identified for PM10. Vehicular emissions (32%), secondary aerosol (13%), marine aerosol (33%) and industrial source (22%) are the sources identified for PM2.5.


  • Microanalysis and source apportionment of Particulate Emissions from anthropogenic sources in two cities, WIT Transactions on Ecology and the Environment, Volume 230, 2018 – Saragur Madanayak Shiva Nagendra, Anju Elizbath peter, Jyothi S. Menon and Avinash Balchandra Akolkar

The morphological and elemental characteristics of ambient particulate matter (PM) collected at two contrasting Indian cities were investigated. Single particle analysis by scanning electron microscopy combined with energy dispersive spectroscopy was carried out on the PM collected at residential, commercial and industrial sites in Delhi and Chennai cities during winter and monsoon seasons. The more diversity in morphological and elemental composition of PM in Delhi city was observed as compared to Chennai city revealed the complexity in source characteristics. The trans-boundary pollution sources were also found to be a major contributor in Delhi city. Mineral particles with a mixed origin of crustal and anthropogenic sources were identified as most abundant species in ambient air, irrespective of types of sampling locations. Even though combustion borne particles were found to be dominant in both the cities, their characteristics were entirely different. The meteorological conditions were also having a profound influence on particle morphology. Source apportionment of PM by UNMIX model indicated that biomass burning and coal combustion (30%) and re-suspension of traffic induced crustal elements (19%) to be the dominant source contributors in Delhi. Vehicular emissions and sea salt spray (30%), biomass and garbage burning (20%) were the identified potential source contributors to PM in Chennai. The present study indicated that source-based abatement strategies will be helpful to abate the present particulate pollution faced by Indian cities.


  • Urban Emission led by Sarath Guttikunda under their program Air Pollution Knowledge and Assessment City Program (APnA), have conducted a source apportionment study. The study reveals that Chennai needs at least 38 Continuous Monitoring Stations for efficient reporting. The study also shows that the major contributor to PM5 is the Transport sector which contributes to almost 24.6% followed by Dust emission which is approximately 23.5%. They have given a few findings and recommendations.

B. Pervious Year Trend

  • Pervious Year Data is available on the Tamil Nadu Pollution Control Board website. Data availability is from year 2017 – 2020

A. City-specific studies

  • Effects of ambient air pollution on respiratory and eye illness in population living in Kodungaiyur, Chennai, Atmospheric Environment, Volume 203, 2019 – Mariselvam Ammasi Krishnan, Kartikeyan Jawahar, Vasudevan Perumal, Thiruselvi Deveraj, Amudha Thanarasu, Devaraj Kubendran and Subramanian Sivaesan

 In this study, a survey of the diseases onset in the locality Kodungaiyur was conducted to bring out the effects mainly due to PM2.5 on human beings. The diseases surveyed include mostly allergic complications in the lungs, eye, and ENT. The results showed associations between pollution exposure and increased percentage of infection in the age group from 21 to 30 years, with a confidence level of 95%.

  • Real-time Vehicular Air Quality Monitoring Using Sensing Technology for Chennai, Transportation Research, 2019 – P. Partheeban, H. Prasad Raju, Ranganathan Rani Hemamalini, and B. Shanthini

Air pollution in urban areas is posing a great threat to urbanites all over the world. Various factors which contribute to air pollution are industrial, commercial and domestic activities. Statistics show that among these sources, motorised transportation is the highest contributing air pollution in recent past. Further, it may increase unless any major mitigation measures are planned and implemented. Therefore, assessing quality of the atmospheric air for breathing time to time is very important to control further damage. Currently, to access air quality-related data is limited. To overcome this, authors have designed and developed an air quality monitoring instrument (AQMI) using solid-state gas sensors and GPS module. It was used to measure the air pollution levels at Chennai city in real time and analysed the air pollutants levels in two different periods and suggested mitigation measures. Air quality on four routes in Chennai has been measured in 2013 and 2017 and compared in order to study the impact of air quality due to Vardhah cyclone. Four routes are considered in Chennai, namely Avadi to Tambaram (route 1—R1), Neelankari to T. Nagar (route 2—R2), Avadi to Chennai central (route 3—R3) and Tonakela camp to Redhills bus stand (route 4—R4). It is observed that the air pollution monitored in 2013 on the three routes shows about 60–70% locations having concentrations exceeding Central Pollution Control Board (CPCB) norms and one route has exceeding values at three places. After monitoring air quality in 2017, it was found that at some places, the pollution levels are increased when compared to that of 2013 due to further increase in vehicular traffic as well as Vardhah cyclone. Air quality data obtained using AQMI could serve various applications. Health conscious people could also take advantage of this to navigate through pollution-free areas. Patients with air pollution-related health problems would find data valuable to determine the less polluted routes.

  • An analysis of the implications of air pollutants in Chennai, International Journal of Ambient Energy, Volume 41, Issue 2, 2018 – M. Arulprakasajothi, U.Chandrasekhar, D. Yuvarajan and Maradana Bhanu Teja

Chennai is one of the fast-progressing metropolitan city which is battling against air pollution. Recent reports from the coastal resource centre have shown that the air quality in Chennai is alarmingly toxic and pollution-linked deaths are increasing every day. Ambient air pollutants such as PM10, PM2.5, O3, SO2 and NO2 are well known for their toxic nature and ability to cause many respiratory disorders like bronchitis, emphysema and asthma. For maintaining a sustainable development and ecological balance, it is vital to optimise ambient air quality. In the current research paper, we focus on the overview of ambient air quality in Manali, an industrial area in Chennai. The paper presents explicit results on the change in ambient air quality in this area over the duration of 30 days and the various reasons behind it.

  • Characterization and phytotoxicity studies of suspended particulate matter (SPM) in Chennai Urban Area, Journal of Environmental Biology, June 2014 – M.Durga, S. Bharathi, P. Balakrishna Murthy and T. Devasena

The paper discusses the affect of suspended particulate matter on the plants. Chennai in Tamil Nadu was selected as study area. The study sites chosen were T. Nagar and Adyar.The SPM (PM and PM ) were collected on glass fibre 10 2.5 filters by a high volume sampler (Envirotech APM 460N4, New Delhi, India), kept at a height of 2m from ground level. The collected samples were sealed and refrigerated at 4°C till further analysis. The collected SPM was analyzed with HRSEM/EDX (FEI Quanta FEG 200) according to EPA guidelines (US-EPA, 2002). Around 300 particles per SPM sample were analyzed for their size, morphology and chemical composition. The overall results of the present study suggest that treatment of Bacopa monnieri explants with different concentrations of DEPs (treatment I) and PEPs (treatment II) induced significant phytotoxicity in the treated groups. This was evident from decrease in % shoot induction (Fig.4a); decrease in number of shootlets/ explants (Fig.4b); decrease in % inhibition of DPPH radical and decrease in the total chlorophyll and protein content of DEP treated groups as compared to control groups. PEP treated group was found interfere significantly with % inhibition of DPPH radical (p< 0.05) only as compared to control. No significant changes were found in other parameters of the PEP treated groups.

  • Nature of air pollution, emission sources and management in the Indian Cities, Atmospheric Environment, Volume 95, 2014 – Sarath K. Guttikunda, Rahul Goel and Pallavi Pant

The study has analyzed six Indian cities including Chennai, it studies the sources of air pollution, emission inventory and dispersion modeling, potential for air pollution control, regulations, and policy implication. The Study has found that the main contributor to PM10 in Chennai is the Transport sector.

  • Chemical Characterization of PM10 for Metals in Ambient Air of Chennai, India, Journal of hazardous, Toxic, and Radioactive Waste, Volume 16 Issue 2, 2012 – D.G. Gajghate, Balvinder Talwar, P. Pipalatkar and Tushar Pustode

The study was undertaken to assess the effect on ambient air concentration of PM10 and metals attributed to various localized activities at different land-use locations in Chennai City, India. The study for PM10PM10, toxic metals, and correlation of metal and source apportionment analysis has been carried out at industrial, commercial and residential locations in the city. The monthly PM10 levels showed a significant variation among locations, and annual averages of PM10 were below the CPCB standards. Among the metals analyzed, Zn was found to dominate in all the monitoring locations. The source apportionment studies have indicated that oil burning emissions, waste incinerators and resuspension of road dust are major sources of PM10 in the study region.

  • Development and Application of Spatially Disaggregated Exposure Series in Time-series Analyses of Air Pollution – related health effects in Chennai, India, Epidemiology, Volume 22, Issue 1, 2011 – Santu Ghosh, Priscilla Johnson, Sheela Ravinder, Moumita Chakraborty, Moti Mittal and Kalpana Balakrishnan

The primary focus in the study was on developing a representative exposure series of PM10 for Chennai population in order to estimate the associated relative risk (RR) for all-cause mortality within the limitations imposed by routinely collected retrospective data and to validate the estimates of RR by modelled PM10, PM2.5, and O3 data. Our estimates obtained using empirical data are robust and comparable to similar estimates from other countries. The development of methodological refinements to address specific data limitations (missing measurements and small footprints of AQM) could be useful for routine analysis in the developing country where similar issues prevail. However, the modelled data estimates indicate the relative inability of the emission inventory-based models to capture daily difference in emission. But the refinements being made are expected to improve their application in India.

  • Fine particulate phase PAHs in ambient atmosphere of Chennai metropolitan city, India, Environmental Science and Pollution Research, 2010 – Rangaswamy Mohanraj, Goovindaraj Solaraj and Selvaraj Dhanakumar

Airborne fine particulates (PM 2.5) and its associated polycyclic aromatic hydrocarbons (PAHs) are reportedly hazardous in urban environment due to the presence of multiple emission sources. In this study, fine particulates collected from fourth largest metropolitan city of India, Chennai, were extracted and analyzed for 11 PAHs by highperformance liquid chromatography equipped with a fluorescence detector.

PM 2.5 values varied between 27.2 and 190.2 μg/m3, while average concentration of particle-associated PAHs determined was in the range from 325.7 to 790.8 ng/m3, which signaled an alarming pollution level in Chennai. Factor analysis suggested vehicular emissions inclusive of petrol- and diesel-driven engines as probable sources.

  • Economics of air pollution in Chennai City, India, Journal of Social and Economic Development, Volume 11, Issue 1, 2009 – J. Sacratees

This paper estimates welfare loss due to the hazardous air quality of Chennai City, a fast-developing metropolitan city in South India. The loss of welfare was estimated using econometric methods like Logit and Tobit Models in order to introduce Willingness to Pay (WTP) to improve urban air quality. The primary data collected through household surveys were used in the estimation model. Measuring and valuing the health impact of air pollution is very complex and the available methods of economic valuation are often rudimentary. We analysed how the monetary value of health benefits could be increased by reducing air pollution, which will be useful to policymakers to reduce the incidence of respiratory illness in the urban population of Chennai City. The economic costs associated with these health risks were then evaluated using available economic information. It enabled us to measure the cost of illness and man-days loss, wage loss, cost of medicine and cost of hospitalisation due to air pollution. Thus, this study addresses the current status and consequences of air quality, which causes concern in developing countries.

  • Measurements of Urban Ambient Air Quality of Chennai City, Indian Journal of Air Pollution Control, Volume 8, Issue 1, 2008 – T. Senthilnathan

The main objective of the study is to determine the background concentration of the pollutants in correspondence with different local activities. It has been observed that annual mean values of particulate matter exceed NAAQS values by large amount. However, gaseous pollutant concentrations are well below recommended values.

  • Air Quality monitoring in Chennai, India, in the summer of 2005, Journal of Hazardous Materials, Volume 136, Issue 3, 2006 – M. Pulikesi, P. Baskaralingam, D.Elango, V.N. Rayudu, V. Ramamurthi, and S. Sivanesan

The study deals with the characteristics of hourly and daily mean surface O3 under different climatic conditions, such as temperature, relative humidity, wind speed and wind direction and other pollutant concentrations. During the summer of 2005, concentrations of surface ozone (O3), oxides of nitrogen (NOx), respirable suspended particulate matter (RSPM) and total suspended particulate matter (TSPM), relative humidity (RH), wind speed (WS) and wind direction (WD) were collected over successive periods of about 24 h at five sites. UV photometric ozone analyser was used to measure the concentration of surface O3. The TSPM values were exceeded the National Ambient Air Quality Standards (NAAQS) at Koyambedu, Mandaveli, Taramani and Vallalar Nagar study area.

  • Traffic Operating Characteristics and its impact on Air Pollution in an Urban Area – A case study of Chennai, India, proceedings of the Eastern Asia Society for Transportation Studies, Volume 5, 2005 – S.Velmurugan, T.S. Reddy, E. Madhu, and I.Prasad Rao

This paper describes operating characteristics of traffic and quantification of traffic and air pollution loads on major road network of Chennai City. The main objective was to make a realistic assessment of total number of vehicles and develop database and technique to estimate road traffic and pollution loads in the city. The study concludes that the roads in Chennai are presently carrying the traffic volumes higher than their capacities with reduced speeds and associated delays. The operating speeds of the traffic on major road network of the city are higher as one goes away from the inner areas of the city. To achieve maximum efficiency in traffic operations, it is proposed to develop the major arterial road network of the city as express route system having grade separators and signal free environment.

  • Key airborne pollutants – Impact on Human health in Manali, Chennai, Current Science, Volume 90, Issue 3, 2005 – V.Jayanti and R. Krishnamoorthy

Exposure to air pollution is an inescapable part of our urban life. In this study, the interaction patterns of air pollutants, SO₂, NOx, SPM and PM₁₀ are investigated based on measured database of the study area in Manali, near Chennai. This study is necessary, since these pollutants violate the prescribed norms of the NAAQ Standards. The air quality of SPM and PM₁₀ based on exceedance factor for industrial average was assessed. It was found to fall under the moderate pollution category and this position is maintained. The health risks due to air pollutants are quantified by estimating the relationship between air quality and health effects. Health related information was gathered through survey and the result is presented in spatial form. This study found that the inhabitants of Manali and surrounding villages were affected by respiratory problems, asthma, and premature death. Thus, the environmental concerns prevailing in Manali are a serious issue.

  • Stochastic analysis for vehicular emissions on urban roads – A case study of Chennai, Proceedings of the Third International Conference on Environment and Health, Chennai, India, 2003 – Harikrishna M. and Arun C.

The unbridled growth of the vehicular population has resulted in the deterioration of environmental quality in urban areas in developing countries. The concentration of obnoxious gases like carbon monoxide and suspended particulate matter continue to pose a major health hazard for the public. In this respect, the urban roads of Chennai, one of the metropolitan cities in India, were chosen for the study. The vehicular population was categorised as heavy-duty vehicles, 2 Stroke Two wheelers, 4 stroke two wheelers, autorickshaws, diesel cars and Post 1984 cars and Pre 1984 cars based on the classification criteria of the Tata Energy Research Institute. The Carbon Monoxide emissions from different modes of vehicles were collected and analysed for the adequacy of sample size using t- test. The sample size was found to be adequate for a confidence level of 90 %. The Probability density function was fitted to the data using Input Analyser developed by Rockwell Software Inc. The results indicate that the Carbon monoxide emission of various categories of vehicles follow Beta distribution function. The results obtained from the study can be used by decision-makers to predict the level of carbon monoxide emissions from the vehicular traffic on the urban roads of Chennai city. This can be used in the formulation of a simulation model to predict an accurate level of pollution in urban roads.

  1. News articles
  • Polluted air hurting Indian cities economies: Hyd, B’luru, Chennai may lose over 4% GDP, The News Minute, 8th September, 2020

  • ‘Ensure oxygen cylinders don’t become part of life’: Climate actividt Ridhima Pandey writes to PM, The New Indian Express, 8th September, 2020

  • ‘Warrior Moms’ Launch Nationwide Pollution Campaign Amid Covid, NDTV, 7th September, 2020

  • How much air pollution you’re exposed to in traffic depends on if you use air-conditioning or not, Fast Company, 10th August, 2020

  • ‘Chennai’s air almost as clear as in Europe’, Business Line, 8th July, 2020

  • Chennaiites breathed better than residents of other southern metros during lockdown: Study, The New Indian Express, 3rd June, 2020

  • Chennai Air Pollution: What long term exposure has done to residents of Thiruvottiyur, The New Indian Express, 28th 2019

  • Chennai: Air pollution down by 35% over pre-lockdown levels, shows study, Times of India, 13th May 2020

  • Chennai air pollution: Normalcy returns, but challenges remain, The New Indian Express, 13th November, 2019

  • Chennai Smog: Air Pollution levels reduce thanks to easterlies, The New Indian Express, 12th November, 2019

  • Chennai Smog: 10 Tips to protect yourself from air pollution, The New Indian Express, 11th November, 2019

  • Chennai smog: Light Rain has helped but air quality still worry this Sunday, Business Line, 10th November, 2019

  • Chennai Smog: Air quality no better on Friday; Sri Lanka, too, begins coughing, Business Line, 8th November, 2019

  • Chennai Smog: Air quality dips to alarming levels, The New Indian Express, 6th November, 2019–air-quality-dips-to-alarming-levels-2057499.html

  • Is Delhi’s polluted air causing smog in Chennai? The Hindu, 5th November, 2019

  • Chennai air quality slips to ‘poor’ levels, smoggy conditions to prevail, The New Indian Express, 5th November, 2019

  • Air Quality in Chennai is unhealthy, say various agencies, Business Line, 5th November, 2019  

  • Smog in Chennai: Is Delhi’s air pollution the cause? The News Minute, 4th November, 2019

  • Air quality in Chennai poor post Deepavali, The New Indian Express, 29th October, 2019

1. Urban Local Bodies notification on Air.


2. Communication Portal for local government (e – governance) – Complain Redressal portals.


3. Public engagement activities.

A. CAST Study 

B. Technical Knowledge Sharing

A. Way Forward 

B. Tool Kit