Alcohol Gas Sensor MQ-3

What a great project to build an Arduino powered breath alcohol sensor and learn with Arduino at the same time.

You'll probably need one of these with it to make soldering easier too

This alcohol sensor is suitable for detecting alcohol concentration on your breath, just like your common breathalyzer. It has a high sensitivity and fast response time. Sensor provides an analog resistive output based on alcohol concentration. The drive circuit is very simple, all it needs is one resistor. A simple interface could be a 0-3.3V ADC.

Please review the datasheet for conversions to ppm then Wikipedia.org for BAC.

Features:

• 5V DC or AC circuit
• Requires heater voltage
• Operation Temperature: -10 to 70 degrees C
• Heater consumption: less than 750mW

Dimensions:

• 16.8mm diameter
• 9.3 mm height without the pins

Documents:

• Datasheet
• Arduino Tutorial in Portuguese