It is an alcohol detector which can detect the alcohol greater than its threshold value defined . Arduino UNO is a low-cost, flexible, and easy-to-use programmable open-source microcontroller board that can be integrated into a variety of electronic projects. Here it is used to control the MQ3 sensor,buzzer and LED. MQ3 Alcohol Gas Sensor detects the concentrations of alcohol gas in the air and ouputs its reading as an analog voltage.It is suitable for detecting Alcohol, Benzine, CH4, Hexane, LPG, CO.
This type of sensor circuit can be used as a breathalyzer to check a person’s blood-alcohol level. Due to its high sensitivity and fast response time, measurements can be taken as soon as possible.