Understanding AQI Levels: What They Mean for Your Health

Ever looked at a weather app and saw a number like 150 next to “AQI”? That’s the Air Quality Index, a quick way to tell how clean or dirty the air is. The higher the number, the more likely the air can hurt your lungs, eyes, or even your heart. Knowing the AQI helps you decide whether to jog outside, open windows, or stay indoors.

How AQI is Calculated

The AQI takes data from several pollutants—mainly PM2.5, PM10, ozone, nitrogen dioxide, sulfur dioxide, and carbon monoxide. Sensors across the city measure these particles, and the worst‑case value becomes the AQI for that hour. In India, the Central Pollution Control Board follows the same scale used worldwide:

• 0‑50: Good – clean air, you can breathe easy.
• 51‑100: Moderate – some people may start feeling light irritation.
• 101‑150: Unhealthy for Sensitive Groups – those with asthma, kids, or older adults should limit outdoor activity.
• 151‑200: Unhealthy – everyone may feel discomfort; avoid strenuous work outside.
• 201‑300: Very Unhealthy – health warnings for the whole population, stay indoors.
• 301‑500: Hazardous – severe health effects, stay inside, use masks.

Because the index updates hourly, it reflects quick changes like traffic jams or a sudden dust storm. That’s why checking the forecast each morning can save you from a bad day.

Practical Steps to Reduce Exposure

If the AQI is high, you don’t have to lock yourself away. Here are a few easy moves that cut the risk:

1. Plan indoor workouts. Swap a morning run for a home yoga session when the AQI spikes.
2. Close windows and use fans. Keep outdoor air out; a simple fan circulates filtered indoor air.
3. Use an air purifier. Even a modest purifier with a HEPA filter can lower indoor PM2.5 dramatically.
4. Wear a mask. N95 or KN95 masks filter out most harmful particles—just make sure they fit snugly.
5. Stay hydrated. Drinking water helps your lungs clear irritants faster.
6. Check real‑time AQI apps. Apps like AirNow, BreezoMeter, or the CPCB portal give you up‑to‑the‑minute numbers for your exact location.

Long‑term, you can push for cleaner air by supporting public transport, planting trees, and asking local officials for stricter emission rules. Small actions add up, especially in crowded cities.

Remember, AQI is more than a number—it’s a health signal. By checking it daily and acting smart, you keep yourself and your family breathing easier, no matter how the weather shifts.