MINNEAPOLIS (WCCO) — Across Minnesota, the COVID-19 testing positivity rate jumped above 13% Wednesday — the worst in more than a year. And the New York Times says the state has seen a 70% spike in cases over the last two weeks.

That’s why the mayors of Minneapolis and St. Paul re-instated indoor mask mandates starting Thursday at 5 p.m. The rule applies to businesses like stores and restaurants. Fans attending this weekend’s Wild and Vikings games will also need to wear masks.

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By now, you’ve probably tried a handful of different masks, but it might be time to shop around. Experts say the reason cloth masks don’t cut it anymore is because the Omicron variant is so contagious.

Dr. Lisa Brosseau actually did the research on how well our masks protect us.

“There’s a bunch of things that matter,” Brosseau said.

First, the material. Cloth masks offer the least protection, and surgical masks are marginally better. Dr. Brosseau says both are good for errands that take a few minutes, and that’s about it.

“Put it on, go into a store and don’t stay there very long,” she said. “Once you go into a store and you know you’re gonna be there for more than a couple minutes, you’ve got to wear a respirator.”

A 3M N95 respirator mask (credit: CBS)

Dr. Brosseau said a KN95 mask is going to offer you more protection than a surgical or cloth mask, but not quite as much as a respirator like an N95. Legitimate respirators will have things like manufacturer name, the model number, a TC number and the acronym NIOSH, for National Institute for Occupational Safety and Health.

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“It should have two straps, not ear loops. If it has ear loops, it’s not a respirator,” Brosseau said.

So how much better are the respirators?

“You get minutes with a cloth mask or a surgical mask, and you get hours with the respirator,” Brosseau said.

Dr. Brosseau’s research showed protection for over an hour if you wear a respirator. If everyone around you is also wearing them, it jumps to more than six hours.

“There’s no need to go to an N99 or N100 if you can get an N95,” she said.

And make sure they fit well. It’s an investment that gives you protection in return.

The CDC says about 60% of KN95 respirators in the United States are counterfeit. Dr. Brosseau says an authentic respirator should have the following:

* Straps to wear around your head, not your ears
* Manufacturer name and model type (like 3M and N95)
* It will also say NIOSH (spelled correctly)
* It will have a TC number
* You can look up your masks information on the NIOSH website to verify

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Click here for more information on masks from the CDC, including tips to identify a counterfeit respirator.

Erin Hassanzadeh