What is the difference for Medical face mask Air different pressure tester standard from EN14683:2004 to EN14683:2019
All we know the medical face mask has to test the Breathability(differential pressure), which is the delta P value. The standard of EN14683 required this device which measures the differential pressure to draw air through a measured surface area at a constant air flow rate is used to measure the air exchange pressure of the medical face mask material. A water-filled(or digital) differential manometer is used to measure the differential pressure. A mass flow meter is used for measurement of the airflow. However, the standard of EN14683:2004 has been replaced by EN14683:2019 version, for air flow leakage issue, the standard propose higher requests for assuring testing result accuracy. Let us see which requests has been highlighted by EN14683:2019: 1. The internal diameter of the top holder and the bottom holder in the contact area with the filter material shall be (25+/-1)mm. 2. The seal of the top and bottom holder onto the filter material shall consist of a metal-metal contact. A meta