Air flow indicator is specially designed to measure whether the air flow from respirator is positive pressure or not.
Measure method: Plug the end of the airflow indicator in the end of the breathing tube and then press the power switch. While the air flow enters the indicator, the bobber in the indicator will float up, which indicates that it’s positive pressure now and the respirator can be used normally. Otherwise, the respirator is forbidden to be used. The reasons might be lacking power or filter’s resistance. Please check the filters and the electricity quantity of the battery and clean or change filters and recharge the battery timely.
Airflow indicator is made of PC material, good impact resistance and unbreakable.