Some treat it like a badge of honor.
Concertgoers say exhilaration, excitement and chaos are to be found in wading to the front of the audience and throwing themselves into a mosh pit with other fans who love metal and punk music.
The pit thrives on physical contact. Moshers enter jumping and thrashing around, all while slamming into and bouncing off each other to the music. Pits are aggressive but social: It's unwritten law to help people to their feet if they fall; and it's not uncommon for moshers to pat each other on the back or even hug at a song's end as mutual recognition of endurance and toughness.
But not everyone walks away from a pit unscathed. Some don't walk away at all.
Paul Wertheimer, a concert-safety expert, said fans often equate moshing with a roller-coaster ride: There's a sense of danger but it isn't real. This false sense of safety gets fans trampled, seriously injured or killed.
"Old-school rock fans just took it. The new school believes they have a right to a great concert that is reasonably safe — punk, heavy metal, rap, whatever," Wertheimer said. "There has to be a standard of care for rock fans, period. No individual can protect themselves against 10,000 other people."
Wertheimer's Chicago-based Crowd Management Strategies compiles an annual injuries and deaths survey from news and police reports, lawsuits, industry sources and public-information documents. Sampling last year's most dangerous events, Wertheimer surveyed 31 concerts in eight countries and counted 21 deaths, 4,567 injuries, 2,683 arrests and about $524,000 in property damage.
Still, he asserts mosh-pit culture could be made reasonably safe if the people who plan and manage concerts took common-sense steps to protect fans from those who use the pit's anonymity to injure people or sexually assault women.
It's these people to watch for, pit regular Malcolm Jay Gonzalez said during a cigarette break at an Industrial Nation metal show.
"It's a friendly thing but bad apples show up," he said. "Certain people are just there to run into you or just punch you in the face. If you can mark them and stay away from them, you'll be better off."
Pits vary in volatility and mood: The crowd at a hard-core metal Slayer show is typically rougher than that at a pop-punk Sum 41 show.
Ideally, pits are a place where a communal etiquette prevails.
But fans can't rely on etiquette.
"You might have the etiquette and respect it, and all your friends might respect it," Wertheimer said. "But 20 people might come in and don't respect it. Who controls them?"
Providing a safe atmosphere often has eluded pit culture, starting with its emergence during the late '70s and early '80s punk scene.
Pulled out by their hair
Wendy Perelstein, editor and publisher of Colorado Springs, Colo.-based metal magazine Mosh Pit, first saw pits when Metallica played local club DJs in the mid-'80s. Bouncers and security didn't know how to handle it.
"They would pull people out by their hair, thinking they were fighting. People got hurt that way," Perelstein said.
In the early '90s, pits came into the public eye when such music genres as grunge, metal and punk started reaching mainstream audiences. As the masses entered pits, many left with serious injuries.
Taking note, Wertheimer started asking colleagues if they had looked at pits from a safety aspect.
"No big security bruisers, no promoters, no venue operators — none of them were going into the pit. But they are all profiting from it," he said.
So in 1992, at age 42, Wertheimer went into pits at every tough metal, punk and grunge show he could find — concerts such as Slayer, Pantera, Nirvana, White Zombie, Green Day and Nine Inch Nails. He wanted to find out if there were problems, what fans where doing and how they were being treated. He logged more than 100 hours in pits.
To his surprise, he came out with the opinion that they shouldn't be banned. But he came to believe they could be safer.
He presented mosher-friendly guidelines at the 1994 International Crowd Management Conference in Seattle. They include separating moshers from nonmoshers, limiting pit capacities, padding the floor and all hard surfaces, not allowing people younger than 18 into pits, banning stage diving and crowd surfing, and banning certain types of clothing and accessories worn by moshers. (Complete guidelines are posted at www.crowdsafe.com.)
He said he thinks promoters and venues should consider enacting all the guidelines. The pivotal point, he said, is to separate moshers from nonmoshers.
"When litigations started going way up in the '90s and people were suing, it wasn't the hard-core moshers in the slam pit. It was the cheerleader, the 'A' students and the other people near the stage who had paid their money to hear the music and got hit by a 250-pound crowd surfer from behind. Or they get smacked by people in the slam pit who suddenly came out of nowhere," Wertheimer said.
When fans began suing for their injuries, it told the concert industry that fans no longer would accept blame for their injuries.
Concert medic Mike Hill, who supervises emergency services at Denver-area shows, sees crowd-surfing and mosh-pit injuries every summer: orthopedic fractures — mostly wrists and arms; and head injuries when people holding up and propelling crowd surfers in pits drop them; and hematomas and lacerations to the face, head or scalp.
"Generally, (a mosher's) issue is increased testosterone mixed with alcohol," Hill said.
Many European concert organizers banned crowd surfing and stage diving after nine Pearl Jam fans died at the 2000 Roskilde Festival in Denmark. Some U.S. cities and colleges followed suit.
The Rape, Abuse, Incest National Network began working with promoters and artists after four alleged rapes at the Woodstock '99 festival in Rome, N.Y. The organization has since opened sexual-assault information booths at Ozzfest and for artists such as No Doubt and System of a Down, RAINN spokeswoman Jamie Zuiebeck said.
And some promoters are taking extra precautions.
Denver-based promoter Nobody in Particular Presents now puts barricades around the pit, places four to five guards to watch it from the front and one on the stage stairs to watch from above. NIPP also banned wallet chains and spiked bracelets from shows because they saw fans getting hit with or caught on them.
"It's all so common sense," Wertheimer said. "The (concert) industry could solve these problems tomorrow, but they don't want to take responsibility and they don't want to pay for it."