Gas Early Detection and Alert System

Gas Early Detection & Alert System

Arduino-Based Gas Concentration Monitor & Threshold Alert Interface

📊 Operational Overview & Video Guide System Live Demo

This automated safety system actively monitors ambient air quality for combustible gases, including LPG, propane, methane, and smoke, using an MQ-2 gas sensor. Driven by an Arduino Uno microcontroller, the system continuously reads analog voltage levels, updates an I2C 16x2 LCD with real-time sensor metrics, and instantly triggers a buzzer alarm if concentrations cross a predefined threshold.

Default Alert Threshold

⚠️ Value > 400 (Adjustable)

Sensing Target Scope

💨 LPG, Propane, Methane, & Smoke

🛠️ Structural BOM Requirements Hardware List

Procure these standard parts to build this environmental safety detection system:

Target Component Label	Structural Allocation Quantity	Functional Deployment Purpose
Arduino Uno	1 Unit	Primary processing core running continuous ADC sampling and I2C commands.
MQ-2 Gas Sensor Module	1 Unit	Analyzes ambient air and yields analog voltage representation of gas levels.
16x2 LCD with I2C Module	1 Unit	Primary alphanumeric output interface displaying raw values and safety status.
Active Buzzer	1 Unit	Provides audible warning frequencies upon trigger breach.
Breadboard & Hookup Wires	1 Set	Distributes power and connects signal pathways safely.

🔌 Device Interface Pin Maps I/O Infrastructure

Wire the physical sensor, screen, and indicator components to your microboard according to this connection map:

Interface Wiring Configurations:

Device Terminal Pin Out	Arduino Target Pin Mapping	Functional Context
MQ-2 Sensor AO	Analog Input Pin A0	Carries analog gas concentration voltage level
Active Buzzer (+)	Digital Output Pin D8	Drives acoustic alert state high
LCD SDA Terminal	Analog Input Pin A4	I2C Bus Serial Data Interface Pin
LCD SCL Terminal	Analog Input Pin A5	I2C Bus Serial Clock Interface Pin
VCC Pin / GND Pin	Power Pins 5V / GND	Primary 5-volt power distribution

💻 Optimized Production Code Engine Firmware Source

Load this firmware sketch to your device using your preferred Arduino IDE environment:

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// LCD Address (Most LCDs use 0x27 or 0x3F)
LiquidCrystal_I2C lcd(0x27, 16, 2);

const int gasSensor = A0;
const int buzzer = 8;

// Change this value according to your sensor sensitivity
const int threshold = 400;

void setup()
{
  pinMode(buzzer, OUTPUT);
  digitalWrite(buzzer, LOW);

  lcd.init();
  lcd.backlight();

  lcd.setCursor(0,0);
  lcd.print("Gas Detector");
  lcd.setCursor(0,1);
  lcd.print("Initializing");

  delay(2000);
  lcd.clear();

  Serial.begin(9600);
}

void loop()
{
  int gasValue = analogRead(gasSensor);

  Serial.print("Gas Value: ");
  Serial.println(gasValue);

  lcd.setCursor(0,0);
  lcd.print("Gas:");
  lcd.print(gasValue);
  lcd.print("    ");

  if(gasValue > threshold)
  {
    digitalWrite(buzzer, HIGH);

    lcd.setCursor(0,1);
    lcd.print("GAS LEAK!      ");
  }
  else
  {
    digitalWrite(buzzer, LOW);

    lcd.setCursor(0,1);
    lcd.print("Air Safe       ");
  }

  delay(500);
}

Required Software Dependencies: Please ensure that the LiquidCrystal_I2C and standard Wire library extensions are fully active inside your workspace environment to build the system without compilation issues.