FDA Tightens Rules On Cleaning N95 Masks, Says Some Made In China Should Not Be Reused

Federal regulators on Sunday updated warnings on how safe it is to clean and reuse the medical masks hospital and other front line workers rely upon to stay safe while treating COVID-19 patients.

In a press release, the Food and Drug Administration said "in response to public health and safety concerns," it no longer approves of decontaminating and reusing some N95 respirators made in China. It did not say precisely which ones, but said Chinese masks "may vary in their design and performance."

The update came amid a drastic shortage of N95 masks during the coronavirus outbreak, and after nursing groups and scientists earlier raised questions about the safety of cleaning and reusing them. The majority of N95 masks in circulation in the United States were made in China.

The FDA also reiterated standing recommendations from the Centers for Disease Control, which say sanitized masks "should only be used" when new, FDA-cleared N95 masks are unavailable.

It was unclear how this would affect protocols around sanitizing masks, including the one used by Battelle Memorial Institute, an Ohio government contracting giant that won, amid fanfare in April, a $415 million federal contract to clean masks.

But on Monday, the FDA indicated that N95 masks that are FDA-cleared or approved by the National Institute for Occupational Safety and Health (NIOSH) are still permitted to be cleaned and reused. A Battelle spokeswoman on Monday said those approved masks are the only ones it sanitizes and returns to hospitals for reuse.

The onus is on hospitals, she said, to send only approved masks for decontamination.

“Hospitals are given the guidelines, so they are the first line in ensuring only the appropriate masks are sent,” Battelle spokeswoman Katy Delaney said in a statement. “Additional checks are done by Battelle when the masks are received.”

If Battelle receives KN95s — a version considered less safe by U.S. regulators — “they are returned to the hospital or discarded,” according to Delaney.

Battelle received emergency FDA approval for its system after intense political pressure from Ohio officials and President Trump. Battelle said it could clean tens of thousands of masks at once, in cities across the country, using vaporized hydrogen peroxide.

The mask-cleaning has been controversial among nursing groups and some scientists who say it has not been deeply tested. Typically, these masks are tossed out after a single use. But amid the shortage, hospitals have been desperate for a solution.

WBUR first reported on the discrepancy between federal authorities' take on the safety of cleaning and reusing masks in mid-April. At the time, scientists at the National Institutes of Health said the masks could be cleaned three times before it was unclear if they would still be safe, while Battelle has claimed to be able to clean them 20 times.

Battelle continued to stand by that claim. Delaney also said the company has done further testing of the mask-cleaning with Massachusetts General Hospital in Boston.

MGH said it intends to use the cleaning process up to five times per mask. Spokesman Noah Brown said the hospital is “only using N95s that are FDA-approved.”

Scientists at NIH and the University of Massachusetts earlier said the Battelle process does clean the mask fabric. However, scientists are still studying how well the masks' efficacy at filtering out 95% of contaminants persists with the cleanings. The elastic bands that hold the masks on tightly also are said to degrade with cleanings.

The Massachusetts Nursing Association has been critical of reusing masks during the COVID-19 crisis. Judith Pare, the group’s director of nursing, on Monday said it’s often not clear to workers where masks are sourced from.

“Part of the problem is the lack of standardization and transparency around what is provided in some hospitals,” she said. The group is pushing for more masks to be made in the U.S., with easier approval by the FDA and NIOSH.

In a statement, Dr. Anand Shah, deputy commissioner for medical and scientific affairs at the FDA, said: “While we continue to support efforts to meet the urgent need for respirators, we are also doing everything in our authority to ensure health care personnel are adequately protected."

Hospitals and agencies that employ front line workers across the country have touted various systems to clean and reuse masks, including using ultra-violet light.

The FDA also said Sunday it does not authorize the cleaning and reuse of respirators that have exhalation valves.