IoT-Based Air Quality Detection and Monitoring System for Asthmatic Patients

Air pollution remains a major environmental and health challenge, especially for individuals living with asthma. Pollutants such as carbon monoxide, nitrogen dioxide, and sulfur dioxide can worsen symptoms and trigger attacks. This paper presents the design and implementation of an Internet of Things (IoT)–based air quality detection and monitoring system tailored to assist asthmatic patients. The system combines an ESP32 microcontroller with an MQ-135 gas sensor for pollutant detection, a DHT11 sensor for humidity and temperature, and a GPS module for real-time location tracking. When pollutant levels exceed safe thresholds, the system activates a buzzer and sends SMS alerts to caregivers or medical personnel. The data are displayed locally and uploaded to a cloud platform for remote monitoring. Results show that IoT can provide an affordable, portable, and reliable solution for personal air-quality tracking and preventive asthma management.