Metalheads in masks: Philly’s headbangers started a movement that’s gone global.

Michael Wolhberg was scrolling through his Twitter feed late last month when he saw a post by his friend Trevor Shelley de Brauw, guitarist for Chicago rock band Pelican.

It was a mask-appreciation tweet about the upside of face masks, not only for protection against the coronavirus, but also as an image enhancer for a band who might not appear as tough-looking in person as they sound on their recordings.

“This is the only time in my life that I have ever looked like a badass,” de Brauw wrote. “Masks are ... awesome. You could be walking around with the goofiest grin on your face and you look stern as ....”

De Brauw attached a masked photo of himself, as a well as a Washington Post article headlined “Making men feel manly in masks is, unfortunately, a public health challenge of our time.”

“The writer was lamenting a 19-page research paper that was saying men were less likely to wear masks in public,” says Wolhberg, the art director for Decibel, a heavy metal magazine headquartered in Philadelphia. “Some of them said it made them feel weak, or inadequate, or feminine.”

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That gave Wohlberg an idea. He suggested to his editor Albert Mudrian that Decibel — which brands itself as “The World’s Foremost Heavy Metal Authority” as well as being “Extremely Extreme Since 2004” — could put together a gallery of musicians wearing face masks “to help break the stigma.”

“Nobody’s going to look at these big muscular dudes covered in tattoos and think they’re a bunch of wimps,” Wohlberg said. “You’re not looking at the metal scene for people who are associated with weakness.”

Decibel has a print subscription base of 50,000 and a readership that’s 93% male, and Mudrian loved the idea of #GetBehindTheMask.

Wolhberg texted friends like Philly grindcore band Die Choking, whose singer and bass player Paul Herzog has a deeper appreciation of facial coverings than most: He’s a nurse in an intensive care unit at a Philadelphia hospital and often treats COVID-19 patients.

Herzog’s #GetBehindTheMask message to metal fans: “A small change in routine can have a profound effect on many lives, and we are a part of that.”

Mudrian reached out to big guns like Kirk Hammett of Metallica, Rob Halford of Judas Priest, and Ice-T, the rapper and Law & Order: SVU actor who also leads grindhouse metal band Body Count.

Marquee names came aboard, from Max Cavalera of the Brazilian band Sepultura to Skid Row front man Sebastian Bach to Anthrax leader Scott Ian to Germantown’s John Baizley of sludge metal band Baroness.

“It was nearly unanimous,” says Wohlberg. He and Mudrian were hoping to round up 50 or so participants. Before they knew it, they had selfies and mask advocacy statements from nearly 150.

Mike Armine of Philly post-hardcore band Rosetta wrote, “Put a jawn on. Some of us live and work in close quarters.”

Blothar the Berserker of GWAR, who performs with a mask that depicts him as a pig-faced goblin, said: “Wear a ... mask. Masks save lives so GWAR can take them.”

Beau Brandon of Atlanta death metal band Withered wrote, “I wear a mask to further distance myself from the willingly misinformed and self absorbed society that continues to plague the Earth.”

Ice-T quipped, “At this point, wearing a mask has become more of an IQ test. Stay safe MFs!”

Scott Carlson of Repulsion wrote “Wear Your Mask! Otherwise, in the words of Evel Knievel, you’re just ‘a hemorrhoid on the ass of progress!’”

Along with 146 dudes, one woman contributed. Erika Osterhout, bassist of Chthonic Deity, who made a logical argument: “The minor inconvenience of wearing a mask is worth being able to move forward sooner than later.”

“It’s vital,” says Wohlberg. “Not only for the community you live in, but also if you want to see a metal show anytime soon, you really have to take this seriously.”

» READ MORE: Coronavirus has shut down concert tours. How are Philly musicians adapting?

The concert industry has been shut down since March, and metal tours could have more hurdles to clear than most before they can return, he says.

More sedate acts might be able to get back to seated theaters sooner with cautious social distancing, Wohlberg says. “But with the stereotypical metal show, you think of moshing and crowd-surfing and all kinds of wild activity. The whole entertainment industry has taken a big blow, but from our point of view, we have that added limitation because of the way people interact at metal shows.”

The #GetBehindTheMask campaign aims to pound into headbanger heads that those shows will come back quicker if tough guys cover up their faces.

I spoke with Die Choking’s Herzog by phone after he’d completed a 12-hour shift at Thomas Jefferson University Hospital, protected by layers of personal protective equipment as he treated stroke and COVID-19 patients.

His band specializes in grindcore, the furious style that marries hardcore punk with metal and features super-short songs and socially conscious lyrics. Were it not for the pandemic, they’d be headed to London next month to play the UK Deathfest.

The band’s album IV was released last year, with 13 songs that blast by in just over 20 minutes. Song titles like “Cough, Wheeze, Explode” and “Mechanical Ventilator,” which seem to have anticipated the pandemic, were actually inspired by the 2019 fire at the Philadelphia Energy Solutions refinery.

Burnout is a big issue in ICU nursing, with “day in, day out pressures” made more acute by COVID-19, says Herzog, who lives in South Philadelphia with his wife (who is also a nurse) and their three children.

“I’ve been doing it for almost 15 years and somehow have managed to maintain some level of sanity. That’s probably because I have the outlet of music to balance the stress.”

Herzog is all in on #GetBehindTheMask because wearing a mask to help prevent coronavirus transmission is sound science. “It vastly diminishes the potential for the droplets that spread the disease to be transferred from one person to another.”

“It’s important, and honestly it’s such a small inconvenience. Dudes are being rebellious, going, ‘You can’t tell me what to do!,' and wildly throwing their middle finger in the air,” he says.

“In reality, it’s about making a little sacrifice to help those who are less fortunate. Doing something for someone who is vulnerable or in pain: That’s what being tough is.”