YOU WOULD EXPECT the guys in Biohazard to be ticked off about the sudden popularity of rap-metal acts such as Korn, Limp Bizkit and Kid Rock. After all, Biohazard's members helped create this hybrid sound with their self-titled 1990 debut and were faithful to that original vision through the mid-'90s when no one outside their loyal, young following paid much attention. Why shouldn't they resent these headbangers-come-lately?

But Evan Seinfeld, who shares the lead-vocal and songwriting duties in Biohazard, insists that there are no hard feelings. "I think the commercialization of this sound by Korn and Limp Bizkit is going to open up things for us," he argues. "I don't resent these other bands. I like their records. I appreciate that most of them credit us as being pioneers.

"Besides, we could never be like that; our lyrics are too serious and too disturbing. They're never going to play Biohazard at the shopping mall. But we will get more attention because now the genre has a name, rap-metal. Maybe because of the success of Korn, more people will check out Biohazard."

If they check out Biohazard's show Friday at Jaxx or the group's new album, "New World Disorder" (Mercury/King), they will hear Billy Graziadei and Rob Echeverria's heavily distorted guitar riffs played faster than heavy metal but not quite as fast as punk. They will hear the pounding beats of bassist Seinfeld and drummer Danny Shuler brought further up in the mix than on the usual metal or punk record though not as much as on a rap record.

They will hear Seinfeld and Graziadei screaming-rapping-singing the lyrics both individually and in tandem. Those lyrics paint a very bleak picture of a world full of conformist pressures, endless wars, corporate hegemony, rat-race dupes, racism, abusive parents, suicidal teens and dead friends. The singers' response is always one of bitterly angry resistance, but the implication is that they yearn for a more tolerant, less violent, more honest world.

A good example on the new album is "Salvation," in which Seinfeld sings, "Someday I hope to rise above material chains which hold me down/ To turn my anger into love and keep my feet planted on the ground." Read on the page, those lyrics seem fairly romantic and idealistic, but Seinfeld bellows them out with the percussive punch of a rapper and the blind-with-rage howl of a metalhead. It's as if the band's positive impulses, by being so thoroughly denied, have been transformed into a caustic fury.

"I think singing about these negative things gets it out," Seinfeld claims. "That's better than holding it in. The only chance we have of getting rid of our demons is by looking them right in the eye and really wrestling with them. If you try to live in ignorant bliss, you'll end up very unhappy -- and most people I know live very unhappy lives.

"I've been in therapy for 10 years," he reveals, "but the best therapy I've ever had is writing songs about what makes me mad and putting them on a CD. Even better is when people who have bought the CD come to our shows and say, `You guys wrote a song that told my life, so I'm down with you forever.' It's like if you found out you had cancer, that's horrible. But if you go to a support group, it's easier to cope. That's what our shows are like -- group therapy for us and our audience."

The roots of the band's frustration can be found in its founders' hometown of Brooklyn. "It was no la-la land," Seinfeld recalls. "I lost a lot of friends growing up; it was very normal to go to a funeral every two weeks. I didn't know anyone who grew up in a functional family. You either had struggling, working-class families or Mafia families. Some of our earlier songs are a cry for help; others are painting a graphic picture of what was going on.

"For a long time, Brooklyn was all we knew. But Biohazard was our ticket to see the world. Going out and playing in 35 countries made us see that these problems are not exclusive to Brooklyn. Kids all over the world have these same problems. And 90 percent of the world's problems come from lack of communication, whether it's between Bill Clinton and Saddam Hussein or between some 14-year-old kid in Peoria and his parents or between a husband and a wife getting divorced. I myself got divorced a year and a half ago, so I know."

Growing up as an angry white teenager in Brooklyn, Seinfeld was naturally drawn to heavy metal. But he soon discovered that rap songs about the New York streets were a lot more relevant to his situation than rock songs about Satan, Vikings and UFOs.

"We were big fans of rap music in the late '80s," he explains. "I was listening daily to LL Cool J and Boogie Down Productions at the same time I was listening to Motorhead. The connection was they were both completely unpretentious. I mean, I loved Iron Maiden as a kid, but I couldn't write a song about `The Rime of the Ancient Mariner.'

"I could, however, write a song about hanging out on the corner and having to run because the cops were coming. I could write a song about feeling lonely in school because no one understood me. I could write about having a tight crew of buddies and then watching one of them die. Those were the kinds of songs I heard in rap. It was urban folk music -- music by the people and for the people. When I heard Eric B & Rakim, I didn't hear a marketing plan; I heard a kid who was making up rhymes from his heart."

Neither Seinfeld nor Graziadei had conventional, melodic voices, but they both had messages they wanted to get across through music. The singsong recitations of rap and the exclamatory shouts of punk gave them a model for expressing themselves without the restrictions of pop tunefulness. They even borrowed the formula of trading leads within the same song from rap acts like Public Enemy and Run-DMC.

"We were making soup," Seinfeld says. "The stock was metal; the meat and potatoes were punk and hardcore; and the special seasoning was rap and hip-hop. It wasn't like some big plan, those were just the musics we liked. It was real unintentional; when we started singing, it just sounded like rapping and screaming.

"I've been like that since I was a kid. Back in those days, it was rock versus disco -- there was actually fighting in the streets. I didn't choose sides, because if I liked it I liked it; I didn't give in to peer pressure. I was this heavy metal kid with long hair and spikes on my clothes, but I also listened to the Sugar Hill Gang. We were always the outcasts, the black sheep. I guess we still are."

BIOHAZARD -- Appearing Friday at Jaxx. * To hear a free Sound Bite from Biohazard, call Post-Haste at 202/334-9000 and press 8129. (Prince William residents, call 690-4110.)