Mask mandates are back for the Denver metro area. Health experts say it's time to upgrade your cloth mask

Posted: 12:45 PM, Dec 01, 2021
Updated: 2022-01-14 16:05:52-05
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DENVER – You probably threw away your stash of masks after Denver and every other metro area county lifted their mask mandates six months ago. Now that mandates are back though, it may be time for an upgrade.

Denver, Adams, Arapahoe and Jefferson counties all reinstated mandatory mask wearing in public indoor spaces a day before Thanksgiving to prevent the area’s hospital system from collapsing amid the surge of the state’s fifth wave of the pandemic.

The four counties follow others across the state which have implemented indoor mask mandates after pleading with Governor Jared Polis to reinstate the statewide public health order, which he said last week he won’t do, despite mounting scientific evidence that shows masks reduce the spread of the novel coronavirus in communities where they’re mandated.

As cases and hospitalizations tick upward nationwide and questions surrounding the omicron variant remain unanswered for the time being, infectious disease experts say it’s not a bad idea to upgrade your mask game if you’re going to be spending a lot of time indoors as cooler weather sets in.

“Any mask is better than no mask, but the better the mask people wear, and the more people wear it, the better for that community,” said Dr. Alex Huffman, an associate professor of chemistry and aerosol science at the University of Denver who has been studying aerosols for nearly 20 years. “No matter what you wear, it's going to be better than not putting on a mask at all.”

During the early days of the pandemic, the U.S. Centers for Disease Control and Prevention (CDC) as well as the World Health Organization (WHO) advised against using medical-grade masks and told the public they didn’t need them so those masks could be reserved for health care workers who desperately needed them as they were in short supply at the time. That isn’t the case anymore.

While there’s now an ample supply of PPE equipment and higher-quality masks are now widely available to the public, the CDC has been slow to change its recommendations on masks, even after admitting earlier this year the coronavirus is airborne and spreads mostly though aerosols (tiny, infectious viral particles that can float or drift around in the air for hours). It wasn’t until Sept. 10 of this year that the CDC updated its website to say the public can wear higher-quality masks and respirators to help reduce the spread of COVID-19 in their communities.

What should you look for in a mask?

If you’re looking to upgrade, Huffman recommends you look for three important components when shopping around and choosing your next set of face masks: Comfort, fit and filtration.

First, you need to wear something that you're willing to wear. If the mask you’re wearing is uncomfortable to the point you’re not willing to wear it, or you’re going to wear it incorrectly, opt for a slightly less efficient mask.

Second, you need to make sure the mask you’re wearing fits tightly to your face so that the aerosols don't leak out from around the sides. A well-fitted mask should sit snugly against the sides of your face with no gaps around the nose, mouth and chin. Huffman himself has a Twitter thread around the issue of proper fit and the science behind it.

Third, you need to make sure that your mask can block as many aerosols as possible. “The better the mask, the better the filtration, and the better it can protect you from inhaling COVID-19 aerosols,” Huffman said.

There are a lot of masks out there. Which one is the best?

While any type of mask is better than no mask at all, they’re not all created equal in the fight against COVID-19.

N95 respirators (now more commonly referred to as N95 masks) are the gold standard in the U.S. when it comes to high quality, tight-fitting masks. These types of face masks/respirators, which are certified by the National Institute of Occupational Safety and Health (NIOSH), filter out at least 95% of infectious particles, if worn properly.

A recent study out of the University of Waterloo from Ontario, Canada, published in the journal Physics of Fluids found that higher-quality, tight-fitting masks like N95s and KN95s filtered more than 50% of exhaled aerosols that can build up indoors and be inhaled by other people, while masks that had an improper fit filtered about 10% of exhaled aerosols.

If you’ve already started shopping around for higher-quality masks, you may have stumbled upon other types of masks/respirators like KN95s. KN95s are the Chinese equivalent to N95 masks. FFP2 masks are the European equivalent, while KF94 masks are the South Korean equivalent. All these masks/respirators will offer comparable protection as N95s, but again, they must be worn properly and cover your nose, mouth and chin.

In fact, a recent major study published in Science last month found the use of KF94 and KF80 masks in South Korea reduced infection rates of COVID-19 in public transport by 93.5%. If accompanied by social distancing measures, reduction increased to 98.1%.

Higher-quality masks/respirators can be expensive in the long run, so if you’re looking to reuse yours, the U.S. Department of Homeland Security has published information online on disinfecting and reusing N95 masks that can extend their life. As a rule, however, you should not reuse a KN95/N95 more than five times.

For a no-excuse guide to wearing and caring for your face mask, head here.

I can’t afford an N95/KN95 or its equivalents right now. Will surgical masks work?

Yes! A large, randomized controlled trial (the gold standard of scientific evidence) led by researchers at Stanford and Yale, which is currently under peer review with the journal Science, but which was shared with journalists due to its importance for public health as the pandemic worsens around the world, found that widespread use of surgical masks can reduce the spread of COVID-19.

The study tracked nearly 350,000 people from 600 villages across rural Bangladesh after researchers distributed surgical masks and promoted their use. The researchers found surgical masks reduced transmission of COVID-19 by about 11%, with increased protection for people over 60 years old, who were 35% less likely to contract the virus by using a surgical mask.

“Our study is the first randomized controlled trial exploring whether facial masking prevents COVID-19 transmission at the community level,” wrote Ashley Styczynski, an infectious disease fellow and one of the lead authors of the study. “It’s notable that even though fewer than 50% of the people in the intervention villages wore masks in public places, we still saw a significant risk reduction in symptomatic COVID-19 in these communities, particularly in elderly, more vulnerable people.”

Nature reports that even after ten washes, surgical masks were able to filter out 76% of COVID-19 aerosols, compared to 37% filtration efficiency provided by three-layered cloth masks.

“Our study provides strong evidence that mask wearing can interrupt the transmission of SARS-CoV-2. It also suggests that filtration efficiency is important,” said Stephen Luby, a professor of medicine at Stanford and one of the co-authors of the study. “This includes the fit of the mask as well as the materials from which it is made. A cloth mask is certainly better than nothing. But now might be a good time to consider upgrading to a surgical mask.”

If you’re opting for surgical masks, Huffman told Fast Company in early August wearers should improve the fit of their masks by making knots on the ear loops and adapting the top of the mask to the bridge of your nose, as shown in the video tutorial below.

As good as surgical masks can be to stop the spread of COVID-19, if they have gaps and aren’t sitting snugly on your face and covering your mouth, nose and chin, they’re probably not doing much to protect you from potential infection.

Does that mean cloth masks are obsolete now? Should you throw yours away?

Don’t throw your cloth mask into the fire just yet. Remember: Any mask is better than no mask at all, but that doesn’t mean cloth masks can’t be improved if it’s really all you’ve got.

Cloth masks, despite their lower filtration efficacy, still provide some level of protection for both the wearer and the people with whom they come into contact, so long as they have a filter in between two other layers of tightly woven fabric, according to a study by Linsey Marr, an engineering professor at Virginia Tech with expertise in airborne transmission of viruses, air quality, and nanotechnology.

In an op-ed for the Wall Street Journal last year, Scott Gottlieb, the previous FDA commissioner and a current Pfizer board member, wrote that a very good cloth mask (a thick one, made of cotton-polyester blends) may only offer about 30% protection against aerosol transmission. A scarf or bandanna fares even worse at 10% or less, he wrote.

Surgical masks, on the other hand, offer 60% protection to the wearer, depending on quality, Gottlieb wrote at the time. A level 2 or level 3 surgical mask is best.

Gaps in loosely fitted masks do pose a problem and can reduce their effectiveness by 60%, so fabric combinations in cloth masks can potentially provide significant protection against the transmission of virus-laden aerosols.

Luckily for all us, researchers at Colorado State University have created an online app to compare the effectiveness of 29 materials and filter combinations, which is really helpful if you’re a fabric geek and know your way around a sewing machine. The app, for example, shows that a two-ply light flannel mask works better than two-ply quilt cotton. A two-layer bandana does a poor job at protecting the wearer against the coronavirus.

Better yet? You can improve these masks with devices such as a mask fitter or brace for a better, tighter fit. The CDC also has a section on their website on how to improve the effectiveness of your face masks as well as tips on what you should and should not do when wearing masks.

If you have nothing but a neck gaiter, the CDC recommends wearing one with two layers, or folding one to make it two layers. Research by Marr found neck gaiters provided similar protection to cloth masks, with about 50% outward protection for aerosols 1 microns in size and at least 80-90% for aerosols 5 microns in size.

Last but not least, make sure you follow these tips from CleanAirCrew on improving masking behavior not only for yourself, but for those around you as well.

So where can I buy these masks and how do I know that what I’m buying is legit?

One of the downsides to having widely available, higher-quality masks in the market is the issue of credible vendors, suppliers and manufacturers, especially when it comes to KN95s. The CDC warns on its website that about 60% of KN95 respirators in the U.S. are counterfeit and do not meet NIOSH requirements.

For those looking to buy reputable N95 respirators/masks, the CDC website has a section on NIOSH-approved products that are listed by brand.

If the CDC route is too tedious for you, Huffman and other health experts recommend you check out ProjectN95, a nonprofit with established partnerships and a comprehensive vetting process that sells both N95s and KN95s from trusted manufacturers. Masks can also be purchased directly from suppliers such as Bona Fide Masks, which sells KN95s from FDA-authorized Chinese manufacturer Powecom for as little as $.88 cents each. You can also check out DemeTECH, which sells N95s as well as other types of masks for about $4 a piece.

If you don’t want to buy online, Huffman says you can also buy N95 respirators/masks at many local retailers, just make sure you look for the NIOSH stamp on them.

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Another great resource if you’re shopping around for masks is Aaron Collins, a.k.a. “Mask Nerd,” a mechanical engineer at Seagate Technology with a background in aerosol science whose YouTube channel is dedicated to testing high-quality masks with the help of an aerosol lab he set up in his bathroom. His top picks include N95s made by 3M, KN95s made by Powecom, KF94s made by Bluna FaceFit, Happylife and others. He also has some suggestions for kid masks for children aged 12 and under.

Masks are great but they’re not the only tool in the fight against the novel coronavirus

Even if you have the best mask available indoors, relying on it alone to protect you from potential infection is setting you up for failure.

Huffman, along with many other health experts, have emphasized since the onset of the pandemic that preventing infection and transmission of SARS-CoV-2 requires a combination of several non-pharmaceutical interventions (NPIs), the so-called “Swiss cheese model,” which scientists know as the hierarchy of disease control.

At the top of that hierarchy is vaccination. The more vaccinated a community is, the less opportunity a virus has to spread and infect others. But even if you’re vaccinated against COVID-19, you could still get infected and transmit the virus to others due to waning vaccine efficacy. It’s unclear at this time if a booster will confer long-lasting protection or if the omicron variant will evade antibodies from vaccines or prior infection.

And as previously stated by Huffman, vaccination alone is not enough to stop the spread of COVID-19.

Limiting the number of people that are gathered in a shared space, as well as limiting the time you spend in that shared space is important, according to aerosol scientists who wrote a detailed commentary for the Center for Infectious Disease Research and Policy.

Ventilation, especially during the winter months when people are more likely to gather indoors, can also be an effective intervention, scientists say.

Jose-Luis Jimenez, a CU Boulder professor in the Department of Chemistry and Biochemistry – who also specializes in aerosol science – says research has shown you are 20 times more likely to get infected with COVID-19 indoors than outdoors, which is why you should consider doing as much as you can in the outdoors and in less crowded spaces.

Staying home if sick, physically distancing from each other, proper hand hygiene, and wearing a higher-quality, tight-fitting mask can all help cut your risk of getting infected with the coronavirus.

"None of these interventions, absent eliminating contact with other people, is effective on its own," scientists warned. "But the greater the number of interventions implemented, the lower the risk of person-to-person transmission.”

In closing, they said anyone wearing a mask should be aware that the longer they spend in a shared space with other people, the greater the risk of being infected.

“Masks simply do a great job of helping prevent the air that you breathe out from going into somebody else and infecting someone else,” Huffman said. “Whether you're vaccinated or not, there's some possibility that you could be an asymptomatic spreader, so it's important to wear masks when you're in an indoor environment with a lot of people around to help reduce that spread from going from person to person.”