The alcohol gas sensor detects the concentration of alcohol gas in the air and outputs its reading as an analog voltage. The concentration sensing range of 0.04 mg/L to 4 mg/L is suitable for breathalyzers. The sensor can operate at temperatures from -10 to 50°C and consumes less than 150 mA at 5 V.

The MQ3 GAS sensor has a very hight sensitivity to Alcohol gas. The  sensitive  material  of  MQ3 Sensor is  SnO2, which  has  lower  conductivity  in  clean  air. When  the target  alcohol  gas  exist,  the  sensor’s  conductivity  is  higher  along  with  the  gas  concentration rising. MQ3 GAS sensor has high sensitivity to Alcohol, and good resistance to disturb of gasoline, smoke and vapour. The sensor could be used to detect alcohol with different concentration, it is with low cost and suitable for different application. 

Features of MQ3 Alcohol Gas Sensor:-

• High sensitivity to alcohol, gasoline, Smoke and small sensitivity to Benzine..
  
• Fast response and High sensitivity.
  
• Stable and long life.
  
• Simple drive circuit.
  

Application of MQ3 Alcohol GAS Sensor:-

• Drunk Driver detection system
  
• Portable alcohol detector.