National Air Quality Index: Key Insights for UPSC & APSC
The rising pollution levels in Indian cities have changed from a seasonal worry to a serious and constant threat to public health. It is essential to understand how we assess and share the severity of air pollution, especially for those training for civil services. The National Air Quality Index (NAQI) is crucial to government efforts to tackle this problem. It offers important information about air quality that helps shape public health policies. The National Air Quality Index (NAQI) serves as the main initiative for monitoring air quality across the country. Air pollution in India is a critical topic within the UPSC environment syllabus and the APSC environment syllabus. In this article, we’ll explore the significance and functionality of the National Air Quality Index, with an overview for those preparing for the UPSC or APSC examinations.
What is the National Air Quality Index?
The National Air Quality Index (NAQI) is an important tool for understanding the air quality we breathe. It turns complicated air quality data into a single number, along with a color code and description. This makes it easier to understand the potential health effects of outdoor air.
Encompassing six classifications from “Good” to “Severe,” the AQI offers a straightforward overview of air quality. Launched in India on October 17, 2014, it monitors key pollutants like PM10, PM2.5, and NO2. Stay informed and breathe easier with AQI!
Why an Air Quality Index?
Before the launch of the National Air Quality Index (NAQI), air quality information was often too technical for the average citizen to understand. Pollutant information is often fragmented, leaving individuals unsure about the air they are breathing. The Ministry of Environment, Forest and Climate Change (MoEFCC) decided to address this since different levels of air pollution can have other public health impacts, with the NAQI being launched in September 2014 as part of the Swachh Bharat Abhiyan. The Air Quality Index makes complex air quality information easy to understand. It helps people recognize health risks and take appropriate precautions.
If you are preparing for the UPSC or APSC exams, it is important to understand the NAQI well. It was created to help communicate scientific information to the public.
Air Quality Index India
Public communication about health risks and health risk control is the responsibility of government agencies. The National Air Quality Index was launched by the Indian Government in September 2014 in New Delhi, as part of the Swachh Bharat Abhiyan, to measure India’s Air Quality Index.
The Central Pollution Control Board (CPCB) assembled an expert group consisting of medical practitioners, air quality experts, academia, organisations working in advocacy related to air, and SPCBs. A technical study was awarded to IIT Kanpur. In 2014, IIT Kanpur and the expert group provided a recommendation for an AQI scheme for India.
There are six cities in India, including New Delhi, Kolkata, Mumbai, Pune, and Ahmedabad, with continuous monitoring and real-time data recorded.
Instrument to Measure Air Quality
Air quality measuring instruments are the tools used to collect the data that informs the air quality indicators. Air quality monitoring instruments are important to public health and the environment because they provide accurate information regarding the various pollutants that exist in the air. They are helpful in helping us learn the extent of air pollution in India, where the pollution is coming from, and how best to address the problem. The relationship we have with air quality monitoring devices allows us to monitor that air pollution is not affecting us negatively, while working towards an environment that is less polluted and more sustainable.
Some instruments that are used for measuring air quality are:
1. PCE-RCM 05
2. PCE-RCM 8
3. PCE-HFX 100
The Core Components: Eight Pollutants as Air Quality Indicators
The NAQI, or National Air Quality Index, offers a comprehensive overview of air quality by measuring the ambient levels of eight essential pollutants. These pollutants are important in understanding the impact of air quality on public health. Given their importance, questions about these key air quality indicators are often asked in both Prelims and Mains examinations of UPSC and APSC. The eight pollutants are:
1. Particulate Matter (PM10)
These are inhalable coarse particles with a diameter of 10 micrometres or less.
- Sources: Dust from construction sites, landfills, agriculture, wildfires, and industrial sources; pollen and mould spores.
- Health Effects: Can irritate the eyes, nose, and throat. Prolonged exposure can lead to respiratory issues.
2. Particulate Matter (PM2.5)
These are fine, inhalable particles with a diameter of 2.5 micrometres or less. They are far more dangerous than PM10.
- Sources: Combustion from vehicles, power plants, and industries; residential heating; and chemical reactions of gases like Sulphur Dioxide (SO2) and Nitrogen Oxides (NOx).
- Health Effects: Due to their small size, they can penetrate deep into the lungs and even enter the bloodstream, causing cardiovascular problems, respiratory diseases like asthma and bronchitis, and premature death. The effects of air pollution on health, particularly from PM2.5, are particularly severe.
3. Nitrogen Dioxide (NO2)
This is a highly reactive gas.
- Sources: High-temperature combustion processes, primarily from vehicle emissions, power plants, and industrial boilers.
- Health Effects: Aggravates respiratory diseases, particularly asthma, leading to coughing, wheezing, or difficulty breathing. It also contributes to the formation of ground-level ozone and acid rain.
4. Sulphur Dioxide (SO2)
A toxic gas with a pungent, irritating smell.
- Sources: Burning of fossil fuels (coal and oil) by power plants and other industrial facilities; smelting of mineral ores containing sulfur.
- Health Effects: Affects the respiratory system and the functions of the lungs. It can also irritate the eyes and is a primary cause of acid rain, which damages forests and aquatic life.
5. Carbon Monoxide (CO)
A colourless, odourless, and poisonous gas.
- Sources: Incomplete combustion of carbon-containing fuels such as gasoline, natural gas, oil, coal, and wood. Vehicle exhaust is a major contributor.
- Health Effects: Reduces the amount of oxygen that can be transported in the bloodstream to critical organs like the heart and brain. High concentrations can lead to dizziness, confusion, unconsciousness, and even death.
6. Ozone (O3)
Ground-level ozone is a harmful air pollutant and a key component of “smog.”
- Sources: It is not emitted directly but is created by chemical reactions between oxides of nitrogen (NOx) and volatile organic compounds (VOCs) in the presence of sunlight.
- Health Effects: Can cause chest pain, coughing, throat irritation, and airway inflammation. It can worsen bronchitis, emphysema, and asthma.
7. Ammonia (NH3)
A colourless gas with a characteristic pungent smell.
- Sources: Primarily from agricultural activities, including livestock manure and fertiliser application.
- Health Effects: In low concentrations, it can irritate the eyes, nose, and throat. High levels of exposure can cause severe respiratory injury.
8. Lead (Pb)
A heavy metal that is toxic to humans and animals.
- Sources: Historically, from leaded gasoline. Currently, major sources include metal processing industries such as smelters, battery manufacturing, and waste incinerators.
- Health Effects: It is a neurotoxin that can affect the nervous system, kidney function, immune system, and cardiovascular system. Children are particularly vulnerable to its effects.
As you prepare for UPSC and APSC examinations, it is essential to keep this list in mind. One trick question you might encounter in the Prelims includes pollutants such as carbon dioxide (CO2) or Methane (CH4). Be prepared to spot which of these does not factor into the National Air Quality Index calculation. Stay sharp and ready for anything that comes your way.
Calculation and Categorisation of the National Air Quality Index
Understanding the Air Quality Index (AQI) is simpler than you might think. Each pollutant has its sub-index, indicating the amount present in the air. To determine the National Air Quality Index (NAQI), we identify the highest sub-index, which reveals the “dominant pollutant” at that time. In essence, the AQI serves as a snapshot of the most significant pollutant currently affecting our air quality.
The National Air Quality Index (NAQI) is identifiable in six colours, allowing for simple understanding by the public.
| Air Quality Index (AIQ) Range | Category | Colour Code | Health Advisory |
| 0-50 | Good | Dark green | Minimal impact. |
| 51-100 | Satisfactory | Light Green | Minor breathing discomfort to sensitive people. |
| 101-200 | Moderate | Yellow | Breathing discomfort to people with lung disease, such as asthma, and discomfort to people with heart disease, children, and older adults. |
| 201-300 | Poor | Orange | Most people experience breathing discomfort on prolonged exposure. |
| 301-400 | Very Poor | Red | Respiratory illness occurs with prolonged exposure. Effects may be more pronounced in people with lung and heart diseases. |
| 401-500 | Severe | Maroon | Affects healthy individuals and has a serious impact on those with pre-existing diseases. |
The environment section of the UPSC and ASPC syllabus includes questions about the National Air Quality Index of India and the measures implemented to reduce air pollution in India. It also addresses the effects of air pollution on health.
The National Air Quality Monitoring Programme (NAMP)
The data entered into the NAQI is sourced from the National Air Quality Monitoring infrastructure. The National Air Quality Monitoring Programme (NAMP) is overseen by the Central Pollution Control Board (CPCB) and regulates the stations that monitor air quality. A network of monitoring stations is located throughout the country.
- Objective: Examine current air quality and trends, identify cities that do not meet air quality standards, and develop effective solutions to prevent and fix these issues.
- Implementation: The CPCB conducts this program through its Continuous Ambient Air Quality Monitoring Stations (CAAQMS) and manual monitoring stations with its State Pollution Control Boards (SPCBs).
- Expansion: Initial NAMP monitored four pollutants (SO2, NO2, Respirable Suspended Particulate Matter-RSPM/PM10, and Suspended Particulate Matter-SPM), but now the system has changed to monitor all eight pollutants needed for the NAQI at many locations.
Understanding Air Pollution in India
Air pollution in India is a major environmental issue, impacting public health, economic productivity, and quality of life. Rapid industrialization, urbanization, and greater vehicle emissions over the past few years have contributed to the problem during this time. The topic of air pollution in India is an important one in the UPSC and APSC environment syllabus. If you are a civil service aspirant, you need to have a thorough knowledge of air pollution in India.
What is Air Pollution?
Air Pollution is the contamination of the atmosphere with unwanted substances that are harmful to human health, the environment, and can also affect climate issues. Contaminants that cause air pollution are called Air Pollutants. They can be gases, particulates, or a mixture of the two and come from a variety of sources. Air Pollution is, in fact, one of the main types of Environmental Pollution.
Severity of Air Pollution in India
Air quality in India has markedly declined over the last two decades. Most air pollution in the world occurs in India today, and this large level of air pollution is taking a significant toll on the nation’s health and economy.
- In 2021, around 97% of India’s population was exposed to particulate matter (PM2.5) levels exceeding World Health Organization (WHO) recommendations, leading to health risks.
- There is growing concern about the rapid increase in air pollution across India, particularly in urban areas.
- Air quality has worsened, with many cities failing to meet health-based status levels.
- Severe particulate pollution is affecting most cities collectively, compounding public health issues.
- Newer pollutants and sources, such as nitrogen oxides and air toxics, are adding to the existing problems.
- Small and medium-sized cities are also experiencing a significant rise in pollution levels.
Effects of Air Pollution in India
Air pollution in India presents serious, multi-dimensional threats to India as a nation and its population. Some of the major impacts of air pollution in India are listed below:
- Health Effects: Air pollution in India creates serious health problems, including respiratory illnesses and heart disease, which result in early deaths. In 2015, it caused about 1.1 million deaths, and this number is expected to reach 1.7 million by 2030, according to the Health Effects Institute (2018).
- Environmental Effects: Air pollution harms ecosystems by contaminating soil and water. This affects plant and animal populations. Sulphur dioxide and nitrogen oxides can cause acid rain. Greenhouse gases like carbon dioxide and methane contribute to climate change.
- Economic Effects: Air pollution in India incurs significant economic costs. It reduces agricultural productivity and crop yields, increases public health expenses, and lowers labor productivity. The estimated economic impact of air pollution on the Indian economy exceeds $150 billion annually.
Government Policies on Air Pollution in India
The National Air Quality Index (NAQI) is not only a policy for controlling air pollution in India, but also an important tool for sharing information. It works within a larger set of government efforts to reduce air pollution in India. To truly understand how we can improve air quality together, it is important to understand the Government policies on air pollution.
1. National Clean Air Programme (NCAP): Initiated in 2019, this is a comprehensive, long-term, time-bound national strategy to address air quality across the country, aiming to achieve a 20%–30% reduction in PM2.5 and PM10 concentrations by the target year, using 2017 as the base year. The National Air Quality Index (NAQI) provides information on cities that are designated non-attainment cities under the National Clean Air Program (NCAP).
2. Graded Response Action Plan (GRAP): The GRAP is an emergency preparedness model in place for the Delhi-NCR region. GRAP institutionalizes actions that can occur when the AQI crosses a predetermined threshold (e.g., Poor, Very Poor, Severe). Actions can include banning diesel generator sets, shutting down brick kilns, and instituting odd-even vehicle policies.
3. Bharat Stage (BS) Emission Standards: India leapfrogged from BS-IV to BS-VI emission norms in 2020, a significant step towards reducing vehicular emissions, a primary source of urban air pollution.
4. Commission for Air Quality Management (CAQM): A statutory body established to coordinate and oversee air quality management in the National Capital Region and adjoining areas.
National Air Quality Index: Challenges Faced in India
The National Air Quality Index (NAQI) is a great initiative with the potential to change how we improve the national air quality monitoring. However, it faces several important challenges that we must address. Overcoming these challenges is crucial to fully realize the benefits of NAQI and improve our quality assessment systems.
- Inadequate Monitoring Network: The existing number of Continuous Ambient Air Quality Monitoring Stations (CAAQMS) is not enough to adequately monitor the extensive geographical area of India, particularly in Tier-II and Tier-III cities, as well as rural regions.
- Issues with Data and Trustworthiness: Technical problems, maintenance challenges, and calibration inaccuracies can result in data inconsistencies, which can erode public confidence.
- Awareness versus Action: Although the National Air Quality Index (NAQI) increases awareness, converting that awareness into effective public action and behavioral change poses a significant challenge.
- Lack of Legal Mandate: Unlike GRAP in Delhi-NCR, there is no nationwide legal framework that automatically triggers stringent actions based on NAQI categories in other cities.
To create a cleaner environment, we need to enhance the national air quality monitoring network, utilize satellite data and low-cost sensors for real-time insights, and integrate air quality data into urban planning. Empowering local communities to take action based on Air Quality Index (AQI) levels is also essential. Together, these strategies will help improve public health and promote sustainability.
Importance of National Air Quality Index for the UPSC and APSC Environment Syllabus
Understanding the National Air Quality Index is important for anyone studying the Environment and Ecology section of the General Studies Paper III for the UPSC Mains. This topic is also a key part of the APSC environment syllabus, so it is essential for aspiring candidates to recognize its role in promoting a healthier environment.
1. The Prelims Examination
Questions can be direct and factual. For example:
- Which ministry launched the NAQI?
- Which of the following pollutants are monitored under the NAQI?
- What does the ‘Maroon’ colour code signify in the AQI?
2. The Mains Examination
Questions are likely to be analytical and require a multi-dimensional understanding. For example:
- “While the National Air Quality Index (NAQI) has improved public awareness, its effectiveness in curbing air pollution remains limited. Critically analyse.”
- “Discuss the key government policies on air pollution in India, highlighting the role of NAQI and the National Clean Air Programme (NCAP) in achieving clean air targets.”
To answer these questions, a candidate must connect the NAQI to larger themes like public health, environmental governance, sustainable development, and the issues in policy implementation.
Conclusion
The National Air Quality Index (NAQI) is important for UPSC and APSC candidates. It draws attention to the serious problem of air pollution in India and gives you the knowledge needed to address environmental challenges in your future career. It helps you understand the links between the environment, health, governance, and technology. This initiative makes environmental information available to everyone and encourages more people to get involved with the issue of air pollution in India. The journey toward cleaner air is long and tough, but the NAQI is a useful tool for both policymakers and the public. To succeed in the environment section of the civil services exams, it is essential for you to understand how it works, why it matters, and its limitations.
Frequently Asked Questions
A: PM2.5 and PM10 are two categories of particulate matter in the atmosphere, identified specifically by size. PM10 has a diameter of 10 micrometers or less, while PM2.5 is 2.5 micrometers or smaller. Both are inhalable, but PM2.5 is more dangerous because it can go deeper into the lungs and can enter the bloodstream.
A: Delhi has the worst air quality in India and consistently ranks as the most polluted capital city in the world. In 2024, its Air Quality Index (AQI) hit 108.3, maintaining this troubling status, according to The Indian Express.
A: On September 17, 2014, the Honorable Environment Minister, Shri Prakash Javadekar, launched the National Air Quality Index (NAQI) under the Swachh Bharat Abhiyan (Clean India Mission) in New Delhi. The first index was launched to provide clearer information to the general public regarding the conditions that affect air quality.
A: Air pollutants are contaminants in the air that are thought to be harmful to the health of humans as well as to the environment. These pollutants can originate from either natural processes or human activities. Some common pollutants include parti culate matter, ozone, sulfur dioxide, nitrogen oxides, carbon monoxide, and volatile organic compounds.
A: India’s National Air Quality Index (NAQI) program originated from the Swachh Bharat Abhiyan (Clean India Mission), which was initiated in October 2014. The aim was to provide the public with air quality information. This task previously required the use of multiple parameters and guidelines, into one simple-to-understand number and color.