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@article{210100,
        author = {Deepa P and Deepak Manikandan J and Nilofer Shainy C and Ranjini N.S and Rohith K and Shiyam Rajkanth J},
        title = {IoT-Based Gas Leakage Detection and Alert System Using MQ-2 Sensor and ESP32},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {5},
        pages = {4252-4258},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=210100},
        abstract = {Undetected gas leaks in homes, kitchens, laboratories and industrial sites can lead to fire, explosion and injury, and a local alarm alone cannot reach people who are away from the premises. This paper presents the design of a low-cost, IoT-oriented gas-leakage detection and alert prototype built around an MQ-2 gas sensor and an ESP32 microcontroller. The controller samples the sensor output and compares it with a configurable threshold. When the threshold is exceeded, it sounds a buzzer, sends a single SMS alert through a GSM module, and drives a servo to demonstrate a predefined mechanical response on a low-voltage model. An alert-state flag prevents repeated messages during one event and re-arms the system when the reading returns below the threshold. Because the decision is made locally on the ESP32, the audible alarm remains available when the cellular network is not. The paper describes the architecture, hardware interface considerations, calibration approach, control logic and safety considerations, and defines a validation protocol covering calibration, response time, SMS delivery and fault tests. The available project documentation does not include calibrated concentration data or repeated-trial measurements, so no accuracy or response-time claims are made. The system is a prototype and not a certified safety device.},
        keywords = {Internet of Things (IoT); gas leakage detection; MQ-2 sensor; ESP32; GSM; SMS alert},
        month = {October},
        }