D.C. fire department officials are reviewing two incidents this week of long response times by ambulances, including one in which a woman died after waiting at least 15 minutes to be taken to a hospital.

In the first, which occurred Monday night, firefighters were dispatched to a house in the 3500 block of Rittenhouse Street NW to aid a woman who had suffered an asthma attack and had gone into cardiac arrest. The firefighters, who also are emergency medical technicians, called for an ambulance but waited at least 15 minutes for one to arrive, according to neighbors.

The woman, Sheila M. Langevin, 58, was taken to Sibley Memorial Hospital, where she died, fire officials said.

The second incident occurred about 5:30 p.m. Tuesday when firefighters were sent to the 5000 block of Nash Street NE to help a woman suffering from abdominal pains. Firefighters on the scene called for an ambulance three times, but none arrived until 7:25 p.m., fire officials said.

The woman, Zella Rempson, was in stable condition last night at Georgetown University Hospital.

Fire department spokesman Ted Holmes said officials plan to review audio tapes of the incidents to determine whether to begin an official investigation.

The incidents occurred only a week after the fire department implemented a policy in which firefighters respond to all medical emergencies to determine if an ambulance is needed. At the same time, the department began using a new computer-aided dispatching system to help cut response times.

Holmes said that fire trucks responded to the two calls within "four or five minutes," and that he did not know what caused the ambulance delays.

"In both of these incidents, the fire engines responded within an acceptable time period," Holmes said. "Our concern is getting trained EMTs {emergency medical technicians} to the scene, and that's what we've been doing."

Sources said Tuesday's delay may have been caused by a snag in the new dispatching system. "Communications apparently just somehow lost the call in the system," one fire department source said.

The ambulance delays were criticized by Thomas N. Tippett, president of Local 36 of the D.C. Firefighters Association, who has argued that the new policy of dispatching fire apparatus on medical calls would increase ambulance response times, wear down fire apparatus and be an inefficient use of firefighters.

"During that whole two-hour period, that company was out of service for any fire calls," Tippett said, referring to Tuesday's incident. "It's just a matter of time before there's a serious fire and someone gets injured or dies because firefighters are at a scene waiting for an ambulance. It's a game of Russian roulette."

Calvin Haupt, president of the ambulance workers local, said the new system cannot be expected to solve problems immediately. "As with any service in transition, there will be a recurrence of old problems, as well as new ones," he said. "With the new computer system, there are bound to be hitches."