
www.rsisinternational.org
INTERNATIONAL JOURNAL OF LATEST TECHNOLOGY IN ENGINEERING,
MANAGEMENT & APPLIED SCIENCE (IJLTEMAS)
ISSN 2278-2540 | DOI: 10.51583/IJLTEMAS | Volume XV, Issue III, March 2026
With the emergence of Internet of Things (IoT) technology, it has become possible to develop intelligent
monitoring systems capable of real-time data acquisition, processing, and remote supervision. IoT-based systems
utilize sensors, microcontrollers, and cloud platforms to continuously monitor physiological parameters and
detect abnormal conditions, enabling automated alerts and data-driven decision-making.
In this context, the proposed system introduces an IoT-based Health and Alcohol Monitoring and Safety Control
System that integrates multiple sensors, including an MQ-3 alcohol sensor, heart rate sensor, blood pressure
sensor, and DS18B20 temperature sensor, with an ESP32 microcontroller. The system continuously monitors
user conditions, processes sensor data, and compares it with predefined safety thresholds to identify unsafe
situations.
PROPOSED METHODOLOGY
A. System Overview: The proposed system is an Internet of Things (IoT)-based Health and Alcohol Monitoring
and Safety Control System designed to ensure safety in industrial and safety-critical environments. The system
continuously monitors physiological parameters and alcohol levels of individuals before allowing them to
operate machinery or access restricted areas.
The system integrates multiple sensors, a microcontroller, alert mechanisms, and IoT cloud connectivity to
provide automated monitoring, real-time analysis, and remote supervision.
B. System Architecture: The architecture of the proposed system is divided into four major functional units:
sensing unit, processing unit, output unit, and communication unit.
The sensing unit consists of an MQ-3 alcohol sensor, heart rate sensor, blood pressure sensor, and DS18B20
temperature sensor, which are used to collect real-time physiological data.
The processing unit is implemented using the ESP32 microcontroller, which receives sensor inputs, processes
the data, and compares the values with predefined safety thresholds.
The output unit includes an LCD display and a buzzer. The LCD displays real-time sensor readings and system
status, while the buzzer provides an audible alert when abnormal conditions are detected.
The communication unit utilizes the built-in Wi-Fi capability of the ESP32 to transmit sensor data to an IoT
cloud platform for remote monitoring and data storage.
C. Working Principle: The system operates on a continuous monitoring and threshold-based decision-making
approach. Initially, all sensors and modules are initialized when the system is powered.
The sensors continuously measure parameters such as alcohol concentration, heart rate, blood pressure, and body
temperature. The ESP32 microcontroller reads and processes these values at regular intervals.
The processed data is compared with predefined safety thresholds. If all parameters are within safe limits, the
system continues normal operation. However, if any parameter exceeds the threshold, the system identifies the
condition as unsafe.
In such cases, the system activates the buzzer, displays warning messages on the LCD, and can restrict access to
machinery or workplace environments to prevent accidents.
D. Hardware Implementation: The hardware implementation of the system includes the ESP32
microcontroller, MQ-3 alcohol sensor, heart rate sensor, blood pressure sensor, DS18B20 temperature sensor,
LCD display, and buzzer.
The ESP32 acts as the central processing unit due to its high processing capability and built-in Wi-Fi
connectivity. The MQ-3 sensor detects alcohol concentration in breath, while the heart rate and blood pressure
sensors monitor vital health parameters. The DS18B20 sensor provides accurate digital temperature readings.