What Is the Air Quality Index (AQI) and How Does It Impact Your Health?

The Air Quality Index (AQI) is a critical tool designed to inform the public about daily air quality and its potential impact on health. Created to help communities make informed decisions, the AQI translates complex air pollution data into a straightforward measure that reflects how safe the air is to breathe.

What is AQI ?
The AQI is a daily measure of air pollution levels that highlights how current air quality may affect human health. Developed by the Environmental Protection Agency (EPA), the AQI tracks five major pollutants:

• Ground-level ozone
• Particulate matter (PM2.5 and PM10)
• Carbon monoxide
• Sulfur dioxide
• Nitrogen dioxide

Higher AQI values indicate more severe pollution levels and associated health risks, making it an essential tool for assessing air quality in real-time.

# How AQI is Calculated

Countries use different scales to represent AQI, with the United States and India both using a 500-point scale. Here’s a quick breakdown of how it works:

• 0–50: Good
• 51–100: Satisfactory
• 101–200: Moderately Polluted
• 201–300: Poor
• 301–400: Very Poor
• 401–500: Severe

Monitors across cities record pollutant concentrations, which are converted into AQI values using standard EPA formulas. The highest AQI reading among the pollutants becomes the official AQI for the day.

# AQI Categories and Health Impacts

Each AQI range carries different health warnings:

Good (0–50): Minimal or no health impact.
Satisfactory (51–100): Minor breathing discomfort in sensitive individuals.
Moderately Polluted (101–200): Potential breathing challenges for people with lung issues; children and seniors may feel slight discomfort.
Poor (201–300): Extended exposure can affect people with heart and lung conditions.
Very Poor (301–400): Prolonged exposure may cause respiratory issues, especially for those with existing health concerns.
Severe (401–500): Breathing difficulties for healthy individuals; significant risk for those with heart or lung ailments, even with minimal physical exertion.

# Why AQI Awareness Matters

Tracking the AQI empowers individuals, especially those vulnerable to pollution, to take preventive steps. It also helps compare air quality across regions, assess improvements, or identify declines in air standards.

# Who is Most Vulnerable?

Certain groups face heightened risks from air pollution, including:

• People with asthma, bronchitis, or other respiratory illnesses
• Children, whose lungs are still developing
• Outdoor workers and athletes who are often exposed to polluted air
• Healthy individuals who are especially sensitive to pollutants like ozone

With air quality being a vital component of public health, the AQI is a valuable resource for staying informed. Whether you're planning outdoor activities or managing health conditions, the AQI provides timely insights, helping you make choices that support your well-being.