MQ-135 Air Quality Sensor

MQ‑135 Air Quality Sensor – Environmental Sensors
The MQ‑135 is a compact, low‑cost gas‑sensing module that detects a wide range of indoor pollutants, including ammonia, benzene, carbon monoxide, and volatile organic compounds (VOCs)—by measuring changes in electrical resistance. Designed for easy integration with Arduino, Raspberry Pi, and other microcontroller platforms, it gives students a hands‑on way to monitor real‑time air quality and explore how environmental factors affect health and comfort.

What students will learn
Through guided projects, learners will discover how to calibrate sensors, interpret analog voltage data, and translate those readings into meaningful air‑quality indices. They’ll investigate the chemistry behind gas detection, program data‑logging scripts, and visualize trends with charts or dashboards—building competencies in scientific inquiry, data analysis, and coding. The module also sparks discussions about sustainability, urban planning, and the impact of emissions on ecosystems.

Key features

• Broad detection range: Sensitive to NH₃, CO, NOₓ, benzene, and other VOCs.
• Fast response & recovery: Real‑time updates every 100 ms.
• Easy interfacing: 3‑pin (VCC, GND, AO) connection; compatible with most educational boards.
• Adjustable sensitivity: On‑board potentiometer for fine‑tuning.
• Robust design: Durable housing for classroom labs and outdoor field trips.

Why it shines in STEAM education
The MQ‑135 bridges science (chemistry of gases), technology (sensor electronics), engineering (circuit design, prototyping), art (visualizing data with graphs and infographics), and mathematics (statistical analysis of trends). Its hands‑on nature encourages inquiry‑driven learning, collaborative problem‑solving, and real‑world applications making abstract concepts tangible while fostering the critical thinking skills essential for tomorrow’s innovators.