Test method for closed leak test chamber for total leakage rate of medical protective masks
Applicable to the evaluation of the total leakage rate of half-mask medical protective masks (hereinafter referred to as masks)
2,Meet the standards:
YY / T0866-2011 Test method for total leakage rate of medical protective masks
3, the total leakage rate components
Under the test conditions specified by the laboratory, when the subject inhales, the ratio of the concentration of the simulant in the human mask and the concentration of the simulant in the inhaled air leaked from all mask components including the filter element is expressed as a percentage.
The total leak rate is composed of three factors: a leak that the mask does not fit tightly to the face, an exhalation valve leak (for a mask with an exhalation valve), and a leak of filter material.
4,Test method
4.1 Closed test warehouse
The basic requirements for a closed test warehouse are as follows:
a) The closed test chamber cover is on the treadmill, the height should be at least 2 m higher than the treadmill platform; the length should be at least able to accommodate the treadmill:
b) at least a part of it is transparent, allowing outside personnel to observe the progress of internal testing; c) it is required to be closed, and aerosol should be filtered when discharged.
4.2 The test airflow enters the person from the top of the closed compartment through the airflow distributor, and directly reaches the subject's head at a flow rate of not less than 0.12m / s. The concentration of the test reagent in the effective working space of the closed warehouse should be uniform. The airflow velocity should be tested near the subject's head.
Dongguan Huanyi Instrument Technology Co., Ltd.