Coal mines are hazardous environments where workers are exposed to dangerous gases, temperature variations, and possible water accumulation. Continuous monitoring of these parameters is essential to ensure worker safety and prevent accidents. This project presents an IoT-Based Coal Mine Safety Monitoring System designed using an ESP32 microcontroller as the central controller to monitor environmental conditions inside mines in real time. The system integrates multiple sensors including the MQ-2 gas sensor for detecting harmful gases, the BMP180 sensor for measuring temperature, altitude, and air pressure, and a soil moisture sensor to monitor water level conditions in the mine. The collected sensor data is processed by the ESP32 and transmitted through its built-in Wi-Fi module to the ThingSpeak cloud platform for remote monitoring and data analysis. For local alerts and safety actions, the system uses red and green LED indicators, a buzzer, and an I2C LCD display. Under normal environmental conditions, the green LED indicates safe operation. When abnormal conditions such as Gas leakage, high temperature, or water presence are detected, the system activates the red LED and buzzer to warn workers immediately. Additionally, a relay-controlled DC fan is automatically turned ON when the temperature rises beyond the safe limit to improve ventilation. This IoT-based monitoring system provides real-time safety alerts, remote monitoring capability, and automatic response mechanisms, helping to reduce risks in coal mining environments. The proposed system enhances worker safety, enables early hazard detection, and contributes to the development of smart and safer mining operations.    

The features of the project are:

1. Real-time monitoring – Continuously checks gas, temperature, air pressure, and water level in the coal mine.
2. Gas detection – The MQ-2 sensor detects harmful gases and smoke.
3. Temperature monitoring – The BMP180 sensor measures temperature and air pressure.
4. Water level detection – The soil moisture sensor detects the presence of water.
5. Automatic fan control – The DC fan turns ON automatically when temperature becomes high.
6. Safety alerts –
   • Green LED → Normal condition
   • Red LED + Buzzer → Danger or abnormal condition
7. LCD display – Shows sensor values and system status.
8. Cloud monitoring – Sensor data is sent to ThingSpeak using Wi-Fi (ESP32) for remote monitoring.

        Components Used:

• Regulated Power Supply.
• ESP32 Microcontroller.
• MQ-2 sensor
• Water level Sensor.
• BMP180.
• DC fan
• Relay.
• Green LED
• Red LED.
• Buzzer.
• LCD display.

      Software’s used:  

1. Embedded C programming.
2. Arduino IDE for dumping code into Micro controller.
3. Express SCH for Circuit design.
4. Thingspeak API.

      Regulated Power Supply:

               

Block diagram:    

video: