Air Quality Index Monitor (Arduino Uno) Measures AQI with MQ135

Air Quality Index Monitoring Device — Detailed Overview

What it does:

This device continuously measures the quality of air in the surrounding environment. Using an MQ135 gas sensor and a DHT11 sensor, it detects harmful gases, temperature, and humidity. The Arduino Uno processes this data and calculates the Air Quality Index (AQI), displaying results on a 16×2 LCD screen. The output shows both the numeric AQI value and a status message (e.g., Good, Moderate, Unhealthy).

How it works:

1. The MQ135 sensor detects pollutants like CO₂, NH₃, and other harmful gases.
2. The DHT11 sensor adds temperature and humidity readings.
3. The Arduino Uno collects sensor data, runs calculations, and determines AQI levels.
4. Results are displayed on the LCD in real time.
5. Optionally, data can be sent to a smartphone dashboard via WiFi module for remote monitoring.

Who it’s for:

• Students: Perfect for science exhibitions, school projects, and IoT learning.
• Educators: Demonstrates environmental monitoring and sensor interfacing.
• Hobbyists: Great for DIY electronics and Arduino enthusiasts.
• Communities: Useful for raising awareness about local air pollution levels.