"Experiments" with the MQ-3 Alcohol Sensor



The MQ-3 Alcohol Sensor is one of a series of easy to use gas sensors that can be easily connected to an Arduino.  This sensor can be used to measure the blood alcohol content in a person by measuring the amount of alcohol is on their breath.

After work one Friday afternoon I set up the following circuit and test software.  The setup was a lot easier than I thought.


The arduino test code

unsigned int val = 0;

unsigned char PIN = 0;

void setup() {




void loop() {

    val = analogRead(PIN);




The "Experiment"

The data

I will add here the results of the test data:

Wiring diagram and schematic