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Epidemiology Intensive Care Unit

Re-Using N-95 Masks In The Time Of COVID-19

The geniuses at Battelle have done it again. This time, they have invented a process for sterilizing and re-using N-95 masks using vaporized hydrogen peroxide. Battelle Memorial Institute is a non-profit scientific research and development institute here in Columbus, Ohio that is located about 3 blocks from the OSU hospital. Researchers at Battelle were the ones who invented the photocopier (and then launched Xerox Corporation), the cruise control for automobiles, the first nuclear fuel for nuclear-powered submarines, and the reusable insulin pen for injecting insulin for diabetics. In full disclosure, about 25 years ago, I had a grant from Battelle to assist with development of inhaled chemotherapy for lung cancer and that led to my receipt of the endowed Battelle Professorship in Inhalational Therapeutics that I held until assuming my position as the medical director of our hospital.

N-95 refers to a mask that can filter 95% of airborne particles. In medicine, we use N-95 masks when we care for patients with infectious diseases that are transmitted by airborne routes, such as tuberculosis, disseminated varicella, and measles virus. The virus that causes COVID-19 is the SARS-CoV-2 virus and this is believed to be transmitted by droplet spread rather than by airborne spread. Normally, viruses spread by droplets do not require the use of N-95 masks; a simple surgical mask with a plastic face shield will suffice. However, certain medical procedures, such as endotracheal intubation, can result in aerosolization of droplets containing viral particles and that is when the N-95 masks are needed.

For an N-95 mask to work properly, a healthcare worker must be fit tested to determine which specific type of N-95 mask fits tightly against the face. If a type of mask does not pass the fit test, then it will not filter out 95% of airborne particles and is no better than a regular surgical mask. Everyone’s face is shaped a little differently so different people will need different N-95 mask types. All healthcare workers who use these masks are required to get fit tested once a year to ensure that the mask that they are wearing actually does what it is supposed to do. Recently, OSHA declared that men who wear beards should not be fit tested because beards can interfere with a tight fit of the masks. For many years, I always passed my fit test with a specific type of N-95 mask despite my beard but because of OSHA’s rules, I was not able to be fit tested last year. Two weeks ago, our hospital required all men who could be involved in the care of a COVID-19 patient to shave their beards (so that they can be fit tested for N-95 masks) and thus, I shaved for the first time in 37 years!.

N-95 masks have come to the forefront of public consciousness recently because the COVID-19 outbreak is causing many hospitals to run low on N-95 masks. A misconception has arisen that N-95 masks are safer than regular surgical masks plus a face shield. For day-to-day care of patients with COVID-19, this really is not true because unless you are performing a procedure such as endotracheal intubation, an N-95 mask is unnecessary. Overuse of N-95 masks in situations when they are not necessary now will result in inadequate supples of these masks in situations when they are necessary in the future. In addition, the over emphasis on N-95 masks could lead the public to overlook the single most important way to prevent the spread of viruses spread by droplets, namely washing one’s hands after they touch various surfaces that those droplets land on (such as door handles and elevator buttons).

With supplies dwindling, Battelle invented a process for sterilizing N-95 masks so that they can be reused up to 20 times. They built the equipment to process 160,000 masks per day and this would greatly improve the nation’s N-95 mask inventory. However, medical equipment is overseen by the Food and Drug Administration. The FDA would only grant Battelle’s mask sterilization equipment limited approval, meaning that they are only permitted to sterilize 10,000 masks per day and only here in Central Ohio. That’s good news for our hospital because now we can count on a steady supply of masks in the upcoming weeks of the COVID-19 surge. But it is bad news for every other hospital in the United States.

Desperate times call for desperate measures. This may be a time for the FDA to take the desperate measure of cutting through bureaucracy.

March 29, 2020

 

By James Allen, MD

I am a Professor Emeritus of Internal Medicine at the Ohio State University and former Medical Director of Ohio State University East Hospital