Fairfax County fire officials said yesterday there was a three-minute delay in dispatching firefighters to a blaze in a motel that killed five persons last week, but that it was not a "significant delay that would have contributed to the total amount of damage."

Chief George H. Alexander, director of county fire and rescue services, said the fire at Brooks' Manor Lodge on Richmond Highway "had an opportunity to spread before we were ever notified."

The delay was caused when fire dispatchers, following a routine procesdure, checked a street index directory to find out what kind of a building was on fire. "A "screaming" woman first reported the fire at 4:48 a.m. on May 9 but gave only the address of the building before hanging up, Alexander said. The directory check was made, according to Alexander, to determine the appropriate number of fire trucks to dispatch.

Alexander said fire reports indicate the fire had spread to the second-floor apartment of the two-story motel where the five persons were killed before the first report was made. He said it is possible the victims, including two children, were dead before the fire was reported.

Fire equipment should have been at the motel, which housed low-income retirees and transient young people, within five minutes, according to Alexander, but it took six minutes and 22 seconds before the first truck arrived.

The dispatcher was about to send two trucks to the address when a second telephone caller at 4:50 a.m. reported that a motel at 7301 Richmond Hwy. was on fire, according to Arthur M. Smith, chief communications officer for the fire department.

At 4:51 a.m. three fire engines, a truck and rescue squad were dispatched and they arrived at the motel three minutes later, Smith said.

Smith added that even without checking the street index directory a delay of up to 1 1/2 minutes is normal before dispatching fire equipment because dispatchers must manually flip through computer printout sheets to determine what fire company should respond and what equipment is available.

The fire and rescue service has been considering for three years the purchase of a computer-assisted dispatching system that would instantaneously give a dispatcher that information.