A six-month-old Prince George's County law that makes new home construction contingent on ample fire and police service has essentially shut down the pipeline of new projects across the county, planning officials say.

Since the law took effect, none of the 23 new residential subdivisions considered has been approved by the county, said Alan Hirsch, head of the Prince George's subdivision review committee. An additional 13 proposals for 1,039 houses that have not been reviewed are in limbo because of questions about their ability to pass the test, Hirsch said.

Armed with six months of police and fire response data, failure rates and pressure from some state lawmakers, the County Council is considering a measure that would increase the allowed response times and permit builders to take other steps if their subdivisions fail the test.

The law requires police emergency calls, on average, to be answered within 10 minutes and nonemergency calls within 25 minutes. The legislation also set a response time limit across the county of 10 minutes for advanced life support. Fire engines and ambulances have to reach subdivisions in eight minutes in the county's rural tier. In other parts of the county, the fire engine and ambulance wait was set at six minutes.

The council was warned by the building industry and planners that creating a bill tying residential construction to police and fire response times could curtail development in southern Prince George's.

But even the doomsayers never thought the effect would be felt countywide.

The bill "had unintended consequences of shutting down more than the council thought," said F. Hamer Campbell, director of government affairs for the Maryland-National Capital Building Industry Association.

Planners generally divide Prince George's into three regions: the developed urban areas within the Capital Beltway, including Capitol Heights and Seat Pleasant; the developing northern and central suburbs, including Laurel, Largo and Bowie; and the largely undeveloped rural tier in the southern and eastern fringes of the county, including Croom and parts of Upper Marlboro.

In the past six months, 23 projects have gone before the subdivision review committee, the first step in submitting a plan to the county. Seven were denied. Sixteen were withdrawn by the applicants, who had realized they would not meet the law's requirements.

College Heights Estates was one of them. The 22 houses that Mitchell & Best, a Rockville-based homebuilder, want to construct near the University of Maryland at College Park are within a mile of two fire stations.

It is the kind of location most people, including County Council member Douglas J.J. Peters (D-Bowie), thought would have no trouble passing the county's new adequate public facilities test.

Instead, the proposed development would just barely miss the mark, said Lt. Col. Karl L. Granzow Jr., who is responsible for fire response data. Fire engines, on average, would reach the subdivision in 6 minutes, 32 seconds, and ambulances would make it in 7 minutes, 48 seconds.

Of the 23 projects considered, 10 were in the rural region. The others were split between the developed and developing tiers.

Hirsch said his committee usually receives about four cases each month. In the past two months, there have been no new proposals. "That is unheard of. It has never happened, ever," he said.

Ride down Route 301, one of the county's main thoroughfares in the developing suburbs, and it would be hard to believe that the county has put the brakes on development.

Signs for new subdivisions with houses selling for more than a half-million dollars dot the roadway. But the projects were in the pipeline long before the law took effect.

Peters said he was assured by public safety officials that police and fire would be able to meet the standards imposed under the law. The only exception was in the rural tier, which stretches along the Patuxent River into the southern part of the county, where residents have complained that infrastructure has not kept pace with residential development.

"It was a different result than we predicted," Peters said.

Mindful of the Prince George's law, state legislators have passed a law that allows the county to charge a development surcharge only if the council relaxes response time requirements.

The state measure sets a $6,000 surcharge on each home in a new residential development in the county. Builders pay $2,000 for each unit they build in the county's older communities. But to collect the money, an estimated $15 million, the county would have to ease the fire emergency response requirement to seven minutes just for travel time. The law now specifies that the time includes the call for service.

Peters said the state has forced the county's hand.

"We preserved our ability to test, we got the surcharge fee and we were told they'll come back next year and take away our authority if we did not make modifications" to the law, he said.

The council's new approach, which could be voted on this summer, does not spell out what builders would have to do to move projects forward if they fail the test.

But Campbell of the builders' association said that though there are two police districts in the county's rural tier that probably would not meet the new standards, the council appears to be "headed in the right direction."

Thomas M. Himler, the county's budget director, has been assigned the task of putting together guidelines for mitigation that developers could provide if they failed to meet the standard.

He said the "idea is to have them pay for something, whether it's police cars or to help build a fire station -- allow them to mitigate their way out of it."

In the past, when new projects fell short on response time, builders were allowed options. If a development failed on fire response, for example, the county required builders to install sprinkler systems, even in single-family homes.

But at times, county staff allowed sprinklers when paramedic service was out of range.

"I'm not going to let you build in the failed areas unless there is true mitigation," Peters said. "That's probably why there is a lot of angst, because people have been tricked by mitigation before. It is not going to be a quick fix that doesn't solve the problem."

Residents who applauded the county's unorthodox approach to slowing residential development now criticize the council's move to change it.

"I think it's tragic that no one has a backbone," said Carmen Anderson, a civic activist. "Every time we get a piece of legislation that puts a slowdown on development, they act like the sky is falling, and it soon gets undone."

But Peters, who spearheaded the legislation, said the county cannot afford to stop development completely during the boom market.

Thomas R. Hendershot (D-New Carrollton), who was absent for health reasons when the bill was passed in November, said he might have told his colleagues that the legislation was ill-conceived.

"It would not hire more police officers or pay to get more firetrucks," Hendershot said. "All it would do, which it has done, is shut off development activity, which has the possibility to generate revenue to hire more police officers and get more firetrucks."

Granzow said the county does an good job overall in responding to emergency calls. "We actually have a good system in Prince George's County," he said. "I think that is what is missing in the whole debate. We are not a failure by any stretch of the imagination."