A three-alarm fire in the kitchen of the downtown Capital Hilton yesterday morning forced the evacuation of roughly 750 guests and employes, 10 of whom were treated for smoke inhalation.

Bruce Hayden, the hotel comptroller, estimated the damage at $100,000 but Kevin Deverich, the general manager, said repairs would not be that expensive.

The fire, extinguished in 36 minutes, began in a grease duct in the main kitchen about 10:10 a.m. Deverich said a contractor cutting through duct work in the kitchen apparently ignited the grease with sparks from his torch.

Some of those suffering from smoke inhalation were taken to local hospitals, treated and released. Others were treated at the scene. There were no other injuries, fire officials said.

Alerted by loudspeakers, about 400 members of the Association of Junior Leagues, who made up the bulk of the hotel's guest list, streamed out of the building at 16th and K streets NW, along with housekeepers wrapped in hotel blankets, mothers with babies swaddled in suit jackets and bookkeepers with boxes of payroll records. They descended on the Sheraton-Carlton Hotel across K Street, to the consternation of a group gathered there for a meeting on terrorism.

"We've been terrorized by the Junior League," said Diana Conconi, stationed behind a reception table for the Sheraton meeting. "Five hundred women all talking about their clothes."

The junior leaguers maintained an upbeat attitude about the fire. "I have great confidence in the firefighters," said one. Five others posed for a photograph next to the fire trucks.

The Capital Hilton was empty for only about two hours yesterday. On top of the vacated reception desk, a sign read: "When there's no time to check out, zip out."