In response to the highly transmissible and rapidly spreading Omicron COVID-19 variant, public health experts are stressing the importance of wearing masks and face coverings, in addition to highly recommending medical grade N95 respirators.

The Minnesota Daily sat down with University of Minnesota College of Science and Engineering researcher Qisheng Ou and Center for Infectious Disease Research and Policy research consultant Lisa Brosseau to answer common questions about N95 respirators and face masks as COVID-19 cases increase.

With the spread of the Omicron COVID-19 variant, public health experts and officials are stressing the importance of masking while around others or in public. Why is masking needed to mitigate the spread of Omicron specifically?

Lisa Brosseau: “This is an aerosol transmissible organism, which means that it’s inhalable, it’s not just droplets or large particles that are the source of infection, but much smaller particles that stay airborne, you can’t see them. They can easily be distributed throughout the thread of space. Something like a cloth mask or a surgical mask really isn’t going to do a lot of good, isn’t going to prevent outward leakage of small particles and it isn’t going to prevent inhalation of small particles.”

Qisheng Ou: “Face covering will do two things: one thing is to reduce the amount of those droplets that will be emitted by an infected person because it basically covers the nose and the mouth. If a healthy person has a face covering it will also reduce the amount of the virus that that person can potentially breathe in… especially for the Omicron because it seems like it has a higher transmission rate than previous variants.”

What is the difference in material and design of N95 respirators in comparison to other types of masks?

Lisa Brosseau: “First what we really need is something that captures particles of all sizes. What we call N95 respirators and filters are very efficient because they’re tested to ensure that they’re very good at collecting particles of all sizes, because we use them in industrial settings for a wide range of hazardous materials. The second thing we care about is how hard it is to breathe through the filter for the material. It turns out cloth masks or cloth materials, you can get them to be really efficient by piling one layer on top of another. It has to have no leakage around the sides of the face… it turns out that’s the complicated piece of making a good respirator, is how do you design one that fits on everybody’s face well.”

Qisheng Ou: “N95 materials have a very high efficiency generally speaking greater than 95% so that’s why it’s called N95. You probably noticed when you put on your face mask there’s a lot of area that is a gap between the actual mask and your face… that’s where the air can bypass the material so you can have a very efficient material.”

Are cloth masks no longer considered an effective protective mask from COVID-19?

Lisa Brosseau: “I never thought they were very protective to begin with… I would tell people you know wear your mask, especially if it’s the only thing you have but please don’t go spend lots of time wandering around the grocery store, perusing all the aisles and standing in long lines with lots of people, because that cloth mask isn’t going to protect you for very long exposure. You put a cloth mask on, it stops a few of those particles, it may improve your time to an infectious dose for a little bit of time, a few minutes but not hours.”

Qisheng Ou: “For most of the face masks and even the surgical facemask is around 80% to 95% [effective]. For a regular face covering like cloth masks or some other commercial face masks…they can be very low, they can be only 20% efficient compared to 95% for the N95.”

Is there currently any other mask that is as effective or more effective than the N95 respirator?

Lisa Brosseau: “The problem with some of those [other respirators] is that they’re not really expected to fit very well because there aren’t the same requirements for testing in workplaces in a lot of countries that there are in the United States… People ask me ‘well, if I can’t get an N95 National Institute for Occupational Safety and Health (NIOSH) certified respirator what do I do?’. I tell them, the KN95, the KF94 or one of these others might be okay, but you also need to pick something that fits well on your face.”

Qisheng Ou: “Yes and no, because the N95 is definitely not the best respirator in the world, so there are some even fancier respirators like half face respirators you probably see sometimes in the movies or if you go to a home improvement store in the painting section… but the question is whether the general public need to wear it just because of pandemic. In terms of a regular fixture that normal people would likely wear, the N95 is probably the best option.”

What is the price difference between N95 respirators and other types of masks?

Lisa Brosseau: “If you buy larger quantities, the price goes down, obviously. I think the ones that I’ve been buying on Amazon, for the last six months, go for about $1.50 each and as long as you take care of it you can make it last a month or more… I tell people to wear them until they feel sort of dungey or if the straps are too stretched out or if the nose clip doesn’t form anymore, then get yourself another one.”

Qisheng Ou: “Generally speaking, N95’s are like $2 to $5 per case. Of course, if you buy a large quantity they can be even cheaper. Regular face masks or medical grade face masks maybe you pay $1 for five to 10 cases, so there’s quite some difference in the price.”

Following recommendations of public health experts, many different N95 and KN95 respirator options are becoming available for purchase online. Is there a way for people to tell which sellers are reputable or “official” prior to buying masks?

Lisa Brosseau: “Every respirator certified in the United States is required to have the manufacturer’s name, the model number and the NIOSH certification number, which is usually a ‘TC’ and then some other numbers following it on the front of the respirator. So if there’s nothing printed on the front of your respirator then it isn’t a respirator, at least not a NIOSH certified respirator. The next thing is to look up the certification number on the NIOSH website if you’re really worried and see if it matches.”

Qisheng Ou: “The reason it can be called an N95 or KN95 is because they have been certified to pass certain standards…so I’m not really worried too much about the variation quality of N95 or KN95 respirators selling on the market. Of course, because of this regulation, you probably only see some big names selling those products like for N95’s 3M and some other big name manufacturers.”

This interview was edited for clarity and length.