A dozen small children stared bug-eyed at firefighter Louis Berkeszi under a tent at the Fairfax County Fair yesterday as he displayed his on-the-job attire: a 30-pound yellow oxygen tank, heavy cloth fire-retardant suit and black rubber boots.

At high noon, with the temperature in the mid-80s, Berkeszi pulled up his thick collar to show how it protects his neck in a blaze. He demonstrated how to breathe through his oxygen mask.

"Who thinks he's hot inside all those clothes?" a fellow firefighter asked the audience. All hands shot up -- Berkeszi's included.

"I love doing this," Berkeszi, 27, a county firefighter for 5 1/2 years, said later. "It makes it worthwhile. I've had kids scream at me from the street, 'I remember you!' "

Hot was the order of the day at the sixth annual Fairfax fair, a suburban celebration held on the grounds of George Mason University. Fair officials reported two dozen cases of heat exhaustion; among the victims was Lee Ruck, president of the corporation that runs the fair, who was treated at a local hospital and released.

The fair managed to combine elements of rural carnival and city block party. There was a Ferris wheel and pony rides, a two-block-long display of country crafts and stylish jewelry, vendors selling funnel cake and vegetable samosas, and more than 100 exhibitors ranging from Fairfax Covenant Church to Cameo Coutures lingerie. The fair continues today from 10 a.m. to 6 p.m.

Among the early arrivals was Cindy Ayliff, 33, of Falls Church, who competed in the 10-kilometer run, placing second in her age group. The reward was a chance to shake hands with Redskins quarterback Jay Schroeder, who presided over opening ceremonies, and to grab his autograph for her husband Philip. "I guess this means I have to watch football," she joked.

Nearby, sitting on hay bales and sipping soft drinks with her 9- and 12-year-old daughters, was Pat Tavenner of Annandale. The family was considering a hot-air balloon ride, but for now, Tavenner had one thought in mind as she sat gazing at Schroeder. "I was trying to talk them into going up and asking for autographs," she said of her daughters. They didn't budge.

Undaunted by the heat were the proprietors of two dozen or so chili stands who were competing in the state championships, being held during the fair. Polite restraint was not highly prized: the entrees included the Death Row Chili Gang, Buffalo Chip Chili and Cicada Chili ("We waste nothing but the buzz").

"We expect to win every 17 years," said chef Helen Buller of Clifton of her cicada brew. She described the chili as "mostly beef and pork, but we add a little bit of cicada for additional flavor." The resulting taste is "sort of like old socks," volunteered her husband, Levon.

No one was moving very quickly in yesterday's wilting heat, with the exception of small children. One of them was Jordan Hamilton, 2 1/2, who was trying her best to jump up and down on a hay bale under the affectionate gaze of her parents, Petra and Craig Hamilton of Springfield.

"She was here last year in a stroller," Petra Hamilton sighed. "It was a lot easier."

The fair has grown steadily in size since its beginnings. "I'm real impressed," said Louise Mahoney, a jewelry vendor who began exhibiting her wares in Fairfax three years ago. "This show's changed a lot in three years. You didn't used to get the crowds you do here now."