One man was killed and 19 other persons, including 14 firemen, were injured during a brief but intense and smoky fire yesterday at the high-rise Promenade apartment building in Bethesda. As many as 1,000 people were left temporarily homeless, and damage was estimated at more than $200,000.

Fire officials said the blaze was caused by careless smoking.

The fire broke out about 11:30 a.m. in an apartment on the seventh floor, according to fire officials.

John A. Brockwell, 27, of Derwood, property manager for the 18-story luxury apartment building at 5225 Pooks Hills Rd., was killed, apparently as a result of helping tenants escape from the floors affected by the fire.

He and another building employee, Sam Hess, were found slumped in a rear corner of an elevator that arrived at the building's shopping arcade one floor below the lobby and eight floors below the site of the fire, witnesses said.

Both men were blackened with smoke and soot, according to building engineer Don Kolda, an eyewitness. Kolda said he ran for help while others pulled Hess, who was coughing convulsively, and Brockwell, who appeared lifeless from the elevator.

Firemen tried to revive Brockwell, but he was pronounced dead of acute smoke inhalation and cardiac arrest at 12:35 p.m. at Suburban Hospital. Hess was reported in stable condition at the Burn Center of Washington Hospital Center, suffering from smoke inhalation.

Bethesda fireman Ray German, 36, was listed in serious condition at the burn center, suffering from burns on his face, arms and legs.

Officials at Surburban Hospital said two of the five tenants taken there were admitted for observation. They are Abe Pearlman, 75, who suffered acute smoke inhalation and possible cardiac complications, and Carla Golub, 46 who suffered exposure and possible cardiac complications, hospital officals said. They said other tenants and firemen taken to Suburban were treated and released.

Firemen initially were hampered by the malfunction of an internal piping system that is supposed to supply water for fighting fires on the building's upper floors, according to Montgomery County police spokesman Richard Greene. He said the cause of the malfunction had not been determined and that "eventually" the pipes did supply the needed water.

Greene also said a fire-fighting plan under which firemen were supposed to use a particular elevator to reach the higher floors was thwarted when that elevator turned out to be in use. He said firemen then tried to use another elevator, but found it did not work.

Thick smoke from the blaze billowed upward at least as high as the building's 13th floor. Some residents of the upper floors had to crawl on their hands and knees to find their way to escape down stairwells.

Peter Reber, a moving company employee visiting a client on the 13th floor, said, "We passed three of four stairwells before I got to a safe one. I kept open doors and getting a pile of smoke. It was very, very smoky."

According to interviews with several tenants and employees, Brockwell was on the 13th floor with another employee when the building fire alarm sounded. He sent the employee downstairs via the stairwell and took the elevator down to the lobby.

Kolda, the building engineer, said he met Brockwell in the lobby. Brockwell immediately sent him up to the seventh floor to investigate the fire, he said, and joined him there a moment later, But, Kolda said, "The smoke was so thick we couldn't even see the corridor lights."

He said they then went down to the sixth floor to tell tenants to escape. After a few minutes, Brockwell sent Kolda downstairs to the lobby to secure the building's freight elevator for use by fore fighters.

Kolda said he did so, then stepped outside to the back of the building, where the seventh floor apartment faced, to look at the fire. Seeing smoke billowing out of the apartment, he said, he went back in and shut off the water, gas, and electricity for the affected north wing of the 1,500-unit building.

"I was standing here when the elevator came down," he said, pointing to the bank of three elevators at the northern end of the lower level arcade "The doors (of the extrme left elevator) opened and there were John and Sam on the floor. I could hardly recognize them."

The building's tenants, including some in dressing gowns and bathrobes, were directed to the arcade level. One floor above, the lobby filled with firemen from at least seven fire companies, rescue workers and Montgomery County police.