Standard for dust masks
(1) New standard of dust respiratory protection issued by National Institute of occupational safety and health (NIOSH) 42cfr84 on June 8, 1995 (according to filter material classification)
N series: no time limit for protection of non oil suspended particles
R Series: eight hours for protection of non oil and sweat oil suspended particles
P Series: no time limit for the protection of non oil suspension particles and sweat oil suspension particles
Some of the carriers of the particles are oily, and these substances attached to the electrostatic non-woven fabric will reduce the electrical property and make the fine dust penetrate. Therefore, the filter material to prevent the oil-bearing aerosol should be subject to special electrostatic treatment to achieve the purpose of preventing the fine dust.
Therefore, each series is divided into three levels: 95%, 99%, 99.97% (referred to as 95, 99100), so there are nine categories of filter materials.
(2) EU en149 standard (test flow 95L / min):
FFP1: minimum filtering effect 80%
FFP2: minimum filtering effect 94%
FFP3: minimum filtering effect 99%
(3) Australian as1716 standard (test flow 85L / min):
P1: minimum filtering effect 80%
P2: minimum filtering effect 94%
P3: minimum filtering effect 99%
(4) . Japanese mol verification standard (test flow 85L / min):
DS1: minimum filtering effect 80%
DS2: minimum filtering effect 95%
DS3: minimum filtration effect 99.9%
(5) . Taiwan CNS standard.
(6) . China national standard GB 2626-2006 is divided into four categories.
The above inspection standards are all based on the particle size of 0.3 μ M. the detection flow of EU standard is 95L / min, and that of us standard is 85L / min. In China, the suspended particle size for national standard is more than 90% of less than 5 μ m, more than 70% of less than 2 μ m, and the flow rate is 42.5l/min. The idea of "the worst case" is adopted in the inspection and certification of filter materials, that is, the worst conditions are set up when the laboratory tests are carried out.
For example, the calculated diameter of ammoniated sodium salt or DOP oil mist dust particle size of 0.3 μ m in efficiency test represents the size of extremely small particles that are most easily penetrated into the filter material, and represents the breathing volume when engaging in strong physical labor. Before the test, the filter material shall be pretreated with high temperature and high humidity, which represents the harsh working environment. All these aims are to test Under such harsh conditions, if the filter material can reach the corresponding efficiency level through detection, then it will be more effective in practical application to protect the health of workers.