The Centers for Disease Control and Prevention clearly had hipster guys in mind when it issued guidelines for what types of facial hair might interfere with filtering facepiece respirators used to protect against the spread of airborne contaminants and diseases like the coronavirus.

Soul patches and Zorros are OK, the agency says. But guys may want to shave those Van Dykes and mutton chops and Fu Manchus. (And for some reason, the CDC even approves of a Hitler mustache — which it diplomatically calls the “toothbrush.”)

The guidelines, which were first published in November 2017 but resurfaced this week, even come with an eye-popping infographic that illustrates what types of beards and mustaches might prevent a respirator from securing the desired tight seal on the skin around the mouth. (It’s worth emphasizing that the CDC does not recommend wearing a mask to protect against coronavirus unless you are already showing symptoms.)

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CDC

A clean-shaven face, of course, is the most likely to keep the respirator mask’s seal — and even stubble might interfere, the CDC advised.

The agency has also noted that more facially hirsute gentlemen might be able to opt for a more loose-fitting device, such as a powered air-purifying respirator.

Respirators and masks have become hot commodities in recent weeks with the spread of the coronavirus. Worldwide, there are more than 82,000 confirmed cases of coronavirus, according to CNN; approximately 3,000 people have died as a result.

On Wednesday, the first confirmed coronavirus case in the U.S. of “unknown origin” was diagnosed in Northern California. The CDC said “it’s possible this could be an instance of community spread of COVID-19, which would be the first time this has happened in the United States. Community spread means spread of an illness for which the source of infection is unknown. It’s also possible, however, that the patient may have been exposed to a returned traveler who was infected.”