How to Calculate Air Quality Index
What is Air Quality Index?
Air Quality Index quantifies air pollution severity on a 0-500 scale. It helps identify health risks and pollution levels.
Step-by-Step Guide
- 1Calculate AQI from five pollutants: PM2.5, PM10, O₃, NO₂, SO₂
- 2Each pollutant scaled 0-500 based on health thresholds
- 3Reported AQI is the maximum component
Worked Examples
Input
PM2.5 = 35 μg/m³ (moderate), others low
Result
AQI = 100 (Moderate: acceptable air quality)
Health advisory issued
Common Mistakes to Avoid
- ✕Assuming AQI >100 means no activity allowed (depends on individual health)
- ✕Neglecting source-specific pollution episodes
Frequently Asked Questions
What AQI values are safe?
AQI 0-50 (Good), 51-100 (Moderate), 101-150 (Unhealthy for groups), 151+ (Unhealthy).
Why is PM2.5 most important?
Particle size allows deep lung penetration; strong health correlation, especially respiratory and cardiovascular.
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