Most countries have established minimum standards that they require manufacturers to meet the minimum standards of filter performance flow rates inhalation requirements, fitting requirements, exhalation valve leakage requirements and more .
Following are the most common classifications with their respective abbreviations:
Classification/Class Standard
N95 USA (NIOSH-42CFR84
FFP2 European Union (EN149-2001)
KN95 China (GB2626-2006)
P2 Australia/ Newzealand
Korea 1st Class (KMOEL 2017-64
DS (Japan) JMHLW-Notification0 214-2018
Classification/Class Standard | N95 USA (NIOSH-42CFR84 | FFP2 European Union (EN149-2001) | KN95 China (GB2626-2006) | P2 Australia/ Newzealand | Korea 1st Class (KMOEL 2017-64 | DS (Japan) JMHLW-Notification0 214-2018 |
---|---|---|---|---|---|---|
Filter performance-
(must be Xo/o Efficient | > 95% | > 94% | > 95% | > 95% | > 95% | > 95% |
Test Agent | NaCl | NaCl & parafin oil | NaCl | NaCl | NaCl & parafin oil | NaCl |
Flow Rate | 85 L/min | 95 L/min | 85 L/min | 95 L/min | 95 L/min | 85 L/min |
Total inward
leakage(TIL) – tested on human subjects each performing excercises | N/A | < 8% leakage (arithmetic mean) | < 8% leakage (arithmetic mean) | > 8% leakage (individual arithmetic mean) | > 8% leakage (arithmetic mean) | Inward leakage measured & included in User instruction |
Inhalation resistance -max pressure drop | < 343 Pa | < 70 Pa | < 350 Pa | < 70 Pa | < 70 Pa | < 70 Pa |
Flow Rate | 85 L/min | Varied see above | 85 L/min | Varied see above | Varied see above | 40 L/min |
Exhalation resistance – max pressure drop | < 245 Pa | < 300 Pa | < 250 Pa | < 120 Pa | < 300 Pa | < 300 Pa |
Flow Rate | 85 L/min | 160 L/min | 85 L/min | 85 L/min | 160 L/min | 40 L/min |
Exhalation valve leakage requirement | Leak rate < 30 ml/min | N/A | Depressurization to O Pa > 20 sec | Leak rate > 30 | visual Inspection after 300 L/Min for 30 sec | Depressurization to O Pa > 15 sec |
Force applied | -245 Pa | N/A | -1180 Pa | -250 Pa | N/A | -1470 Pa |
CO2 clearance Requirement | N/A | < 1% | < 1% | < 1% | < 1% | < 1% |
On this criteria all the standards are very close and specially the N95 and KN95 are the same. The above 6 classifications and 10 standards that each country require its manufacture to conform with to pass the classification. Some slight difference between the US N95 and China’s KN95 are highlighted in blue.
Most of these difference are small, following are the key differences:
1. The Chinese government requires the manufacturer to run mask fit tests on real humans with ≤ 8% leakage known as the 3D fit. The N95 US standard does not require manufacturers to run fit tests.
2. The US N95 has slightly stricter tests for inhaling and exhaling which help in breathability.
3. N95s also have slightly stricter requirements for pressure drop while exhaling, which should help with breath-ability.
N95s and KN95s are both rated to capture 95% of particles, although only KN95 masks are required to pass fit tests. N95 have slightly stronger requirements for breath-ability. Pursuant to mask manufacturer 3M, “it is reasonable to consider China’s KN95s equivalent” to US N95 standards.
The CDC has approved the KN95 as an acceptable replacement.
04/30/2020
By Kenneth Chang
With doctors, nurses and other health care workers facing acute shortages of protective masks, the Food and Drug Administration announced on Friday that it will allow use of a more widely available mask that meets Chinese standards instead of American ones.
Hospitals across the United States are running out of N95 masks, which filter
at least 95 percent of particles that are 0.3 microns or larger, including the new coronavirus. N95 masks are tested and certified by the National Institute for Occupational Safety and Health, or NIOSH, a research agency that is part of the Centers for Disease Control and Prevention.
On Friday, the F.D.A. issued an emergency use authorization for KN95 masks. Regulated by the Chinese government, they are almost identical in performance to N95 masks. There are slight differences in their specifications, like a variation in the maximum pressure the masks must be able to withstand as a person inhales and exhales.
The C.D.C. lists KN95 masks as a suitable alternative when N95s are not available.
The F.D.A. said KN95 masks were eligible for authorization if they met certain criteria, including documentation that they were authentic.
But many hospitals have not been willing to order KN95 masks because of uncertainty over whether imports would be allowed into the United States as well as potential liability if they turned out to be counterfeit. But for some institutions, that may be a worthwhile risk if the alternative is no masks.
The F.D.A. had on March 24 issued a similar authorization for non-NIOSH masks that met similar standards in other countries in Europe as well as Australia, Brazil, Japan, Korea and Mexico. But it left off China because of concerns about fraudulent masks.
Many N95 masks are also manufactured in China, and the Trump administration is trying to compel companies like 3M to send more of those to the United States.
More masks are available because corona-virus transmission in China has reduced.
“They have so much stock/’ said Leo Freidman, the company’s chief executive, during an interview Thursday. “They ramped up now it ‘s a perfect storm of inventory:’
He said that he understood the quandary the F.D.A. faced because of the danger of counterfeits, but that his company obtains safety certificates and lab reports from its suppliers.
“We have an opinion that these are high enough quality to be used in Chinese hospitals/’ he said of the masks his company is importing. “And the public can make their own deductions.1′
“All you need to know about KN95 Respiratory Protective mask”