Never in the course of human history, with the possible exception of Samson and Delilah, have there been so many people so fascinated with hair.

But then, you really don't expect to find your average Joe at the National Coiffure Championships, the centerpiece of the National Cosmetology Association's 70th annual convention, a three-day smorgasbord of 2,000 nail, makeup, skin and hair divas at the Washington Hilton.

For the last two days, the real action took place in a ring filled with hairdressers furiously clipping, spraying, styling and profiling. The Coif Off is the Olympics of hairdressing -- a chance for the van Goghs of the hair world to snip their way to fame as members of the U.S. team that will go on to the international championships in Rotterdam this fall.

"This is a love affair with hair. It really is. And a love affair with art," said Danny Ewert, coach for the U.S. ladies team selected yesterday at the Washington Hilton.

Each of the hairdressers was judged in three categories: Consumer Day, what the average customer wears on the street; Progressive, the hairdos for the 5 percent of salon business that walks on the wild side; and the real showcase -- the Artistic Day to Gala competition, a category for pure creative genius. "It's art using the medium of hair," said Ewert.

If this is art, it is a precision art. The goal is the best technical haircut in the world, and the competition has the exacting rules of sports competitions.

Each woman model in the Artistic competition, for example, must have a minimum of eight rollers in her hair, with pin curls on three-fourths of the remaining hair. "Wise Men" -- the referees -- watch the floor for illegal substances on the hair, coaching from the audience and the worst no-no: touching hair after time is called. After the wet set, the Wise Men seal the hair net over the rollers before the models go under the dryer. Comb out and styling are rigidly timed.

"It's taking your talents and honing them as fine as they can be," said Ewert, who was on the U.S. team in the 1984 international competition in Las Vegas that won the first U.S. gold medal. He went on to train the U.S. ladies team for the international in Germany, where it won a silver medal for designs inspired by the work of Georgia O'Keeffe -- "The lines, the shape, the way she handles movement," he said.

Georgia would have been a bit surprised yesterday, all things considered.

"What we're judging here is the hair," said Doris Williams, a judge in the Progressive leg of the competition. "The competitors dress their models to complement their hairstyle or to make a story that is a total fashion statement. As judges, we are instructed to judge them strictly for the hair statement."

What about, say, the black hair with the orange neon triangle above the forehead? A tad too progressive for the Progressive category, perhaps?

"You have to say to yourself, 'Is it so fast-forward that it would not eventually be Consumer Day?' " said Williams. "Would it water down to where the majority of people would wear some form of it? A streak instead of the triangle? It could be a look worn by the masses, but it doesn't necessarily have to be as strong a statement."

The same philosophy applies equally to men's hairstyles. The amount of hair spray used in the Gents Artistic competition alone was responsible for blowing a hole in the ozone layer right above the Hilton.

"First we are looking for the neatness, balance and the shape to be square from the front, from the back and from the profile," said Daniel Ruidant, the three-time Gents world champion who will be the U.S. Gents judge in Rotterdam. "And then, creating movement. The hardest part of Artistic Evening is to create lots of movement and keep the shape."

No matter that all of the male models ended up looking like lounge singers. The reason most hairdressers compete is, in fact, a chance to ply their skills at something more exotic, something the average woman or man won't wear to the office.

"My clients are real world, living people," said Ewert, who also works as artistic director for the Stewart's chain of salons in the Midwest. "I don't do a lot of off-the-wall people. So I need a place to vent my creativity that is not going to do anybody any harm. The worst thing in the world for me is 'My God! That guy gave me the weirdest haircut! I can't do anything with it!' "

The unkindest cut didn't come, in fact, from any of the hairdressers in the final competition. It came from the model who broke her partner's heart when she chopped off all her hair and abruptly retired just two weeks before the contest.

Models, as it turns out, play a crucial role in the process. They need to have the right hairline, the right neckline and hair that can withstand up to three bleachings during competition. It's sort of a cross between Miss America and the Kentucky Derby.

"These girls don't just drop out of trees," said Diane Moltaji, a board director of the Chicago Cosmetologists Association. "They're carefully nurtured."

Jo Merola, for example, is a legal secretary who has been modeling for hairdresser Geno Levi for five years. Levi pays for all her travel expenses and outfits for the competitions in exchange for her hair.

"My friends never know what to expect when I come home, but I've never had anyone say they didn't like my haircut," Merola said. Unlike most of the competitors who go for the more show-stopping blond colors, she sticks with a deep red. "I tell you, I think red is pretty hot. I get a lot of comments. I've had men actually come out of their office to tell me 'Your hair looks really nice.' "

Attitude, of course, is very important. Models are carefully dressed and posed for maximum effect. The "I think you're scum" look was especially big in the Ladies Progressive competition, where one woman (orange hair) stood hand on hip, one leg on the chair while another (maroon hair) wore a purple coat, black bra, black tights and silver chains draped across her waist.

But, said hairdresser Steve Tetreault, who was a member of the '88 U.S. team and spent $25,000 last year competing in Europe, "This is not a vanity thing. It's not about the model. It's about the hair. The model is the stage you set it on."

After all, the real stars of the show are the hairdressers.

"It's just a real elite type of people who are looking for more out of life," said Levi, of Washington, Pa. "This sets you apart from regular hairdressing. This puts you on the edge."