Under the authority of the Air (Prevention and Control of Pollution) Act of 1981, India’s Central Pollution Control Board sets national ambient air quality standards and is responsible for both testing air quality and assisting governments in planning to meet such standards. State Pollution Control Boards are permitted to set stricter standards than those in effect nationally.
Conventional pollutant emission limits
Revised National Ambient Air Quality Standards, 2009
Interest in air quality management policies began in India during the 1970s. After the 1972 Stockholm Conference on the Human Environment, it became clear that the nation was in need of a uniform environmental law. As a result, the Air (Prevention and Control of Pollution) Act was passed by Parliament in 1981. With the goal of providing for the prevention, control, and abatement of air pollution, the first ambient air quality standards were adopted in 1982 by the Central Pollution Control Board (CPCB) and revised in 1994 and again in 2009.
Agencies responsible for air quality standard creation and monitoring include CPCB and several State Pollution Control Boards (SPCBs). All of these entities fall under the control of the Ministry of Environment and Forest (MoEF). The CPCB, working together with the SPCBs, provides technical advice to MoEF in order to fulfill the objectives outlined in the Air Act of 1981.
The Air Act mandates the CPCB and SPCBs to:
- Establish national ambient air quality standards for criteria pollutants,
- Assist government in planning future environmental prevention and control strategies,
- Carry out research to better understand environmental issues,
- Undertake nationwide air sampling to ascertain the ambient air quality in India and identification of the problem areas,
- Conduct air quality inspections in areas of concern.1
SPCBs can set more stringent standards than the existing national standards in their respective states. Such a process is similar to the local divisions used within the US EPA.
Another legal document, the Environment (Protection) Act of 1986 , does not specifically mention fuels or emission standards, but does authorize central and state governments to regulate activities that can harm the environment. Current ambient air quality standards are based on the authority of the Environment Act, 1986.
National Ambient Air Quality Standards
|Pollutant||Time Weighted Average||Concentration in Ambient Air|
|Industrial, Residential, Rural and Other Area||Ecologically Sensitive Area (notified by Central Government)||Methods of Measurement|
|O3, μg/m3||8 hours**||100||100||
|Lead (Pb), μg/m3||Annual*||0.50||0.50||
|CO, mg/m3||8 hours**||2||2||
|Ammonia (NH3) μg/m3||Annual*||100||100||
|Benzopyrene (BaP) – particulate phase only, ng/m3||Annual*||1||1||
|Arsenic (As), ng/m3||Annual*||6||6||
|Nickel (Ni), ng/m3||Annual*||20||20||
|* Annual arithmetic mean of minimum 104 measurements in a year at a particular site taken twice a week 24 hourly at uniform intervals.
** 24 hourly or 8 hourly or 1 hourly monitored values, as applicable, shall be compiled with 98% of the time in a year. 2% of the time, theymay exceed the limits but not on two consecutive days of monitoring.
Note – Whenever and wherever monitoring results on two consecutive days of monitoring exceed the limits specified above for the respective category, it shall be considered adequate reason to institute regular or continuous monitoring and further investigation.
The National Air Monitoring Programme (NAMP) is a nation-wide program headed by the Central Pollution Control Board whose purpose is to monitor levels of key air pollutants, report violations, and conduct research on pollution trends. NAMP monitors levels of SO2, NO2, Suspended Particulate Matter (SPM), and Respirable Suspended Particulate Matter (RSPM / PM10) at 342 operating stations in 127 cities across India. The NAMP publishes a list of cities that violate air quality standards, which can be found here.
On 29 November 2011, MoEP announced the expansion of monitoring to include PM2.5 at select locations in major cities.