1. Press and hold the power button for 1 second, the LCD alcohol tester turns on with a beep sound.
2. Warm-up mode countdown for 10 seconds.
3. Test mode countdown from 10 to 00 after warm-up mode, blow in this period.
4. Blow in the inhaler of breath for 3-5 seconds with normal energy after a deep inhalation
5. Read the test result from the LCD alcohol tester.