- A new report finds that the popular KN95 masks are not as effective as N95 masks that have been in short supply.
- However, KN95 masks may have uses outside of high risk areas.
- Masks have been shown to be effective at limiting the spread of COVID-19.
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A new report found signs that popular KN95 masks are not as effective as N95 masks.
Researchers at ECRI found that up to 70 percent KN95 masks imported from China don’t meet U.S. standards for effectiveness as with N95 masks. The group issued a hazard warning in September
Both products are said to filter 95 percent of aerosol particulates. KN95 respirators differ from N95 respirators because they meet the Chinese standard but are not regulated by U.S. agencies.
In the United States, the
“There’s a potential misunderstanding in the public about the two masks,” Dr. Krutika Kuppalli, an infectious disease professor at Stanford University, told Healthline.
More importantly, though, ECRI is worried that doctors and nurses are using KN95s that are not filtering 95 percent of particulates.
A team at the not-for-profit patient safety group noted that 60 to 70 percent of imported KN95 masks do not filter 95 percent of aerosol particulates. ECRI tested about 200 masks from 15 different manufacturers.
Because health systems were purchasing some of the models tested, ECRI chose to raise an alarm and issue an alert to the public.
“Because of the dire situation, U.S. hospitals bought hundreds of thousands of masks produced in China over the past 6 months, and we’re finding that many aren’t safe and effective against the spread of COVID-19,” Dr. Marcus Schabacker, president and chief executive officer at ECRI, said in a press release. “Using masks that don’t meet U.S. standards puts patients and frontline healthcare workers at risk of infection.”
Schabacker hopes healthcare providers will be more critical of masks before purchasing masks.
Healthcare systems are still importing PPE due to widespread shortages. Hospitals report significant challenges ordering masks made in the United States. Some believe they are competing with the U.S. government as it seeks to replenish its PPE stockpile, ECRI said in a statement.
“We have seen a little bit of an ease up on the supply chain,” Schabacker told Healthline. Some health systems and hospitals are still having a difficult time getting PPE, he added.
A spokesperson at the National Personal Protective Technology Laboratory at NIOSH told Healthline that non-NIOSH-approved products should only be used in crisis situations when no other NIOSH-approved N95 respirator or a listed device from one of the other recognized countries is available.
In this case the KN95 masks would only be used as a last resort, although likely a step above a surgical mask.
In these cases, KN95s that meet the requirements of the
Just because the KN95s may not meet NIOSH standards, however, doesn’t mean they’re useless.
“KN95 masks that don’t meet U.S. regulatory standards still generally provide more respiratory protection than surgical or cloth masks and can be used in certain clinical settings,” Michael Argentieri, vice president for technology and safety at ECRI, said in a statement.
Schabacker said KN95s can be used in lieu of surgical or procedure masks for activities that involve limited contact with bodily fluids, as KN95s are not intended for fluid repellency.
But they should only be used as a last resort when treating patients with known or suspected COVID-19.
“Don’t use KN95s at this point in high risk areas,” Schabacker said.
“Hospitals and staff who treat suspected COVID-19 patients should be aware that imported masks may not meet current U.S. regulatory standards despite marketing that says otherwise, Argentieri added.
There are many noncertified masks that have head and neck straps that can ensure air is being filtered, the ECRI statement said. These differ from those with ear loops.
This isn’t the first time mask quality has come into question.
In May, the FDA reissued an emergency use authorization for
A group out of Harvard and MIT known as the Greater Boston Pandemic Fabrication Team (PanFab) evaluated KN95 masks and published results in July. That report also supports the finding that many KN95 masks did not perform to the standards that they claim to meet and are likely to be counterfeit, said Deb Plana, a leader with PanFab.
They looked at masks donated to three hospitals in Boston.
Plana told Healthline that one counterfeit mask they studied even released more particles than were present at the input of the testing apparatus, which corresponds to a negative filtration performance.
That said, not all Chinese-made masks are problematic.
“Some masks marked as KN95s perform to accepted standards,” she said.
The group wants to see masks tested by federal regulatory agencies before they are distributed to healthcare practices, “even in times of crisis,” Plana said.
Schabacker said his team was surprised to find that it wasn’t one brand failing over another. Instead, some masks made by one brand worked and some didn’t.
“That’s even more concerning,” he said.
It’s hard to say if you can trust the masks, as there “doesn’t seem to be a consistent QA [quality assurance] process,” he said.
ECRI will continue assessing masks to provide more insight on quality standards. They plan to look at KF95s, which are made in Korea.
“We’re not saying this is all bad product,” he said.
Schabacker estimates there are about 3,500 manufacturers making KN95s in China.
He emphasized that ECRI didn’t do a representative sampling of masks made by all manufacturers.
While he hopes that some KN95s still live up to the standard, he said he is not sure. Meanwhile, people should check existing KN95s for certification.
“Try to get something from the vendor or have them tested so workers aren’t at risk,” Schabacker said.
“Now that we know about it, we’ve got to do something about it,” he said.
The ECRI warning comes as more than 20,000 counterfeit N95 masks from Hong Kong were seized by border patrol officers in Boston in September.
The Centers for Disease Control and Prevention (CDC) lists
For information on how to evaluate KN95 respirators or those from other countries, consider reading these two articles from the CDC:
Factors to Consider When Planning to Purchase Respirators from Another Country, Including KN95 Respirators from China
- Understanding the Use of Imported Non-NIOSH-Approved Respirators
Plana recommends these tips to evaluate mask quality and see if an N95 is counterfeit.
- Use trusted supply chains.
- For filtering facepiece respirators claiming N95 certification, check for active and correct Testing and Certification numbers on the NIOSH Certified Equipment List (CEL) or the
NIOSH Trusted-Source site.
- Check for similarity to a fraudulent product on the
- For filtering facepiece respirators claiming compliance to a non-US standard (e.g. KN95s, FFP2s), check if masks are on the FDA Appendix A or Exhibit 1 lists of respirators authorized for importation under
EUA. Also check the CDC Assessment Resultsfor Not NIOSH-approved respirators for filtration performance.
- Check for inconsistent markings. No FFP2/3, KN95, DS/DL, P2/3, or PFF product should bear a NIOSH stamp since NIOSH only certifies the U.S. N95 standard (the reciprocal is also true). A list of different respirator certifications by the nation is available at the
- Consider independently performing filtration testing in the absence of verifiable manufacturer information for a specific mask. This can be accomplished by submitting the mask for testing to a CDC- or a NIOSH-approved commercial facility (see the
CDC International Respirator Assessment Request page). Some institutions may want to consider using their own testing apparatus, as described in the methods section of this paper.