Gases such as alcohols, carbon monoxide, and hydrogen sulfide may interfere with the testing of the sensor. Keep away from alcohol, cigarettes (including carbon monoxide), soot (including acrolein), and fruits (including ethanol) before testing. If the detector is exposed to high-concentration air pollutants environment,which will damage the sensor and make it work improperly. Under these conditions, please place the detector in a well-ventilated place for 6 hours again.