See Invisible Pollution — Build an Air Quality Monitor with Arduino Uno and MQ-135 Sensor

Every part needed, pre-tested for compatibility, with an AI build companion trained on this exact project. Shipped from Bengaluru in 3-5 days.

Ever wondered what’s in the air around you? From kitchen smoke to benzene fumes from plastics, the invisible can be harmful. This kit puts the MQ-135 gas sensor in your hands — a sensor used by environmental enthusiasts — along with an OLED screen that turns raw data into a clear Air Quality Index number, backed by red, yellow, and green LEDs that act like a traffic light for your lungs. You’ll wire it all on a breadboard, code the logic, and in under three hours have a monitor that boots up every time you connect a 9V battery.

What You'll Build

An air quality monitoring station that reads concentrations of CO2, ammonia, benzene, alcohol, and smoke. The OLED display scrolls the current air quality as a simple AQI-inspired scale; green means fresh, yellow cautions, red warns you to ventilate. It’s a functional prototype that you can place near a stove, in a workshop, or even carry outside to compare street air to your room. By the end, you’ll understand how sensors talk to microcontrollers and how machines perceive our environment — a perfect first project for anyone curious about smart cities and citizen science.

What You'll Learn

• Connect an analog gas sensor to Arduino and read pollutant levels.
• Drive a 0.96-inch OLED display with I2C communication.
• Map sensor data to an air quality index and trigger traffic-light LEDs accordingly.
• Power a standalone Arduino project from a 9V battery and understand portable electronics.

Kit Contents

Why Buy This Kit Instead of Sourcing Parts Separately

Who This Kit Is For

Young makers aged 5–15 who want to build their first real-world sensing project with adult guidance, CBSE Class 11–12 students preparing a physics or computer science practical, B.Tech ECE/EEE freshers exploring embedded systems, and ATL Tinkering Lab coordinators looking for a ready-to-run air quality module. The project naturally fits science exhibitions, Smart India Hackathon environmental challenges, and hobbyists from IIT, NIT, VIT, or BITS campuses who need a reliable prototype.

Built and Backed by Compoden

Every Compoden kit ships with an AI build companion trained on this exact project — accessible via a QR code on the box, with WhatsApp and email backup. We've spent 10 years building projects for makers, schools, and institutions across India. If a part fails because of a manufacturing defect, replace it free within 7 days.