The D.C. Fire Department, eager to solve a long-standing problem of poor ambulance response times, has found a way to cut them nearly in half. But the solution has brought fire officials almost as much criticism as the problem itself.

For the last three months, the department has sent firetrucks instead of ambulances on calls deemed by dispatchers to be low-priority, even when an ambulance is available. Ambulances are sent only if patients continue to request them after firefighters arrive.

Fire Chief Ray Alfred says the policy change has accomplished the department's goal of reducing the time it takes to get help to people with medical problems. Each firetruck carries at least one firefighter trained as an emergency medical technician.

But many firefighters and other emergency personnel are bitterly opposed to the change, arguing that it delays the transportation of patients to hospitals and increases the risk to those who are more seriously ill than originally believed.

"Basically, using a firetruck as a surrogate for an ambulance is stupid," Howard Champion, director of the MedStar shock-trauma unit of Washington Hospital Center, said last week. "It's an expensive waste of resources and it takes away from the purpose of an ambulance, which is to provide emergency medical treatment and transport to patients who need hospital emergency care."

Alfred, in defending the policy, said that using the city's 50 fire vehicles for medical emergencies has cut the average response time from 10 minutes to 5 1/2, within the accepted national guidelines of six to eight minutes. Experts say fast responses are vital in such emergencies as heart attacks, since brain damage occurs within four to six minutes of cardiac arrest.

"Everyone was battering us over the head about it taking us too much time to get to the scene," Alfred said. "I don't have the luxury of sending an ambulance on every call . . . so I decided I would put as many EMTs {emergency medical technicians} out there as I could."

However, the cost of that achievement has been high and its benefits largely illusory, according to dozens of firefighters and other emergency personnel interviewed in the last three weeks at fire stations and medical emergencies.

They complain that firefighters can do little for people with non-life-threatening problems, and that on those occasions when the medical problems are more serious than originally believed -- as the city says is the case 11 percent of the time -- the delay in getting the patient to a hospital can have serious consequences.

"It's a Band-Aid on a major laceration. It doesn't fulfill the needs of the people of the District of Columbia," said Lt. Michael Smith of Station 9 in Adams-Morgan. "The response time has improved, but the arrival time at the hospital has actually increased."

Experts in emergency medicine say the system puts a heavy burden on the judgment of dispatchers, who must elicit information from often-agitated callers and frequently are unable to get an accurate picture of the emergency.

The death early Sunday of Virginia Natcher, wife of Rep. William H. Natcher (D-Ky.), illustrates the problem. Fire officials say 911 dispatchers received a call at 4:15 a.m. Sunday from the Northwest apartment building where the Natchers live, asking for an ambulance for an unknown emergency. Because it was not initially considered a life-threatening situation, a fire engine was dispatched from Station 20, where it was sitting alongside an idle ambulance.

Firefighters arrived at the apartment at 4:23 a.m. to find that Virginia Natcher, 79, had gone into cardiac arrest. They sent for an ambulance, which took Natcher to Sibley Hospital at 4:49. She arrived there at 4:59 and was pronounced dead at 6:50, a hospital spokeswoman said.

A spokeswoman for Natcher, the former chairman of the District appropriations subcommittee, said the congressman was satisfied with the city's response and that his wife had received all possible medical care.

Alfred said the fire department response was appropriate based on the information given over the phone. Although he said he recognizes that the current system relies heavily on dispatchers making accurate assessments, he said there is little else he can do with existing resources.

"Until I get at least $8 million added to my budget and five years of time, I intend to keep this system in place," Alfred said, referring to the money and time he says he would need to staff 33 ambulance units, the number he said is required to send one on every emergency call.

But firefighters argue that the current system is wasting money in the form of fuel and maintenance expenses.

From June through September, when fire vehicles were sent only on high-priority medical calls, each vehicle averaged 95 medical calls a month, according to statistics obtained by The Washington Post. That average jumped to 168 in October and November, and the number of medical runs has more than doubled at several stations.

"If all the ambulances were out and someone called and they sent us, I could see that," said Capt. James D'Amico Sr. of Station 30 in the Capitol View neighborhood of Northeast. "But when the ambulances are in the area and they don't send them, it just doesn't make any sense."

Records show that Truck 17, which is based at Station 30, logged an average of 792 miles a month in October and November, up from 607 miles a month from July through September. In addition, D'Amico said the truck was out of service for maintenance 18 hours in October and 23 hours in November, figures he called unusually high.

The story is the same all over the city, firefighters say.

"Running up and down the street like we are, it's a lot of wear and tear on the apparatus and a lot of wear and tear on the guys," said Capt. Rogers Massey of Station 19 in Anacostia, where the volume of medical calls has increased 79 percent. "We do this for 24 hours {per shift}, and it burns people out."

The policy also increases the chance of firefighters being on medical calls when a fire alarm sounds, forcing firetrucks from more distant stations to be dispatched.

"On Saturday nights and Friday nights you're going to have whole sections of this city without fire protection, because we're sitting there {with a patient} waiting for an ambulance," said Lt. Thomas N. Tippet, president of Local 36 of the D.C. Firefighters Association.

Ambulance workers also are not satisfied with the change. Their union president, Calvin Haupt, recently wrote to Alfred to complain about the policy, saying that ambulance crews are more qualified to deal with medical emergencies than firefighters trained as EMTs.

Members of the Mayor's Advisory Committee on Emergency Medical Services, including MedStar's Champion, are angry that the policy was implemented without their input and approval. "This was a decision that was seemingly made without any medical consideration," said Mark Smith, chairman of emergency medicine at George Washington University Hospital and vice chairman of the committee.

Nearly 90 percent of cities similar in size to the District send fire vehicles staffed by emergency medical technicians on life-threatening calls, according to a 1990 survey by the Journal of Emergency Medical Services, an authoritative publication that covers the field.

But few employ the "first responder" system for low-priority calls, said its director of research, Jeff Cady, who said he knew of no others that send fire apparatus without simultaneously dispatching ambulances.

Critics of the policy say a better way to accomplish the same thing would be to stop granting transportation to everyone who calls 911. Nearly 40 percent of all emergency medical calls in the District do not result in patients being transported to the hospital.

The current fire department policy prohibits dispatchers from telling callers that they don't require emergency service and forbids firefighters and ambulance personnel to refuse treatment once they have arrived on the scene.

"Not everyone who expects an ambulance ride can have one without the system disintegrating," said lawyer Jim Paige, author of several books on emergency medical services and publisher of JEMS."