Two recreational mainstays of children's playgrounds -- the old-fashioned swing and slide -- are being systematically removed from elementary schools in the Washington area as part of an effort to make the playgrounds safer.

Besides having a history of accidents, the swings and slides do not offer children as much opportunity to be "creative as some other types of playground equipment, school officials say.

"Any principal can tell a horror story about a kid being hit by a swing or falling from the top of a slide," said Marjorie Knutson, health and physical education curriculum specialist for the Fairfax County school system.

An estimated 4,200 injuries -- ranging from broken limbs to minor bruises -- were recorded during the school day on Washington-area elementary school playgrounds last year. Nationally, about 55,000 injuries on school playgrounds last year were serious enough to require emergency room treatment.

School officials seeking to make their schoolyards safer are generally forced to rely on their experience as a guide because the federal government has not provided any guidelines or standards. And because local school systems have different approaches -- and different available funds -- their playgrounds can differ in terms of the type of equipment installed, the surface underneath and the height of the equipment.

One thing the school systems do agree upon is that the old-style swings and slides can be dangerous and are not as stimulating intellectually as other kinds of equipment. The Arlington school system has already removed its swings and slides and other jurisdictions are not replacing them when they wear out. The two elementary schools in Falls Church have retrofitted their swings with plastic, animal-shaped seats that are thought to be safer.

The dangers stem from human factors as much as anything else.

"You have to understand the playground -- 200 kids converging on two or three items of equipment and the bottlenecks that result," Knutson said. "With a slide, with one set of steps, if someone at the top gets frightened and there are 10 kids waiting on the ladder behind, the one at the top can't get back down. The others start pushing and there may be an accident."

Accidents have also been common when children crowded around moving equipment -- swings, merry-go-rounds and seesaws.

When the school systems remove their swings and slides, they replace them with equipment designed to challenge the child's imagination and to accommodate large groups of children.

"If you are sitting in a swing, you can do just one thing," said Fairfax County's Knutson.

To deal with safety and educational concerns, schools here increasingly are using "play complexes," such as the log city, climbing bars and fitness courses in which students can run through a set of activities at different playground stations.

Physical education specialists, in selecting playground materials, also look for equipment that will enable children to develop their bodies and their physical coordination. Climbing bars satisfy those demands, and as a result are among the most common type of equipment found today on school playgrounds.

Local school systems differ greatly on the surfaces they put under their playground equipment.

Montgomery County, for instance, spreads crushed stone beneath the equipment at its 123 elementary schools. "We use it because it is local, it doesn't track into the building and it is economical," said Sandra Johnson, coordinator for elementary and middle school physical education. "Also it doesn't attract cats and dogs [who might use it like an outdoor litter box]."

But some parents are not happy with the material. Patty Moriarty's daughter Meghan broke her arm five weeks ago when she fell from the playground bars at Burning Tree Elementary School in Bethesda. ". . . We would like to have some mulch under the equipment . . . instead of the hardtop," Moriarty said. She described the surface as "a hard surface, like blacktop with gravel."

The school's principal, Naomi Plumer, played down the problem of the surface, describing it as crushed stone -- "very fine, almost powdery." She said that none of the equipment is on a hardtop surface. But, she said, "one of the things that happens with ground covering is, as children use it, it gets kicked away and dispersed. It is gone in a short time and you have to replace it."

Here is a summary of the surfaces local school systems use and why:

District of Columbia. About 90 percent of the 126 elementary schools have asphalt beneath the equipment, according to Dominic Angino, safety director. The rest have "safety surf," a rubbery cushion material. Angino said the District should replace the asphalt with pea gravel or safety surf but has not because of the cost.

Fairfax County. The 128 elementary schools use "blue stone dust," a fine crushed gravel, said Gordon Lawrence, assistant coordinator of safety. He said the county decided not to use sand, because it attract animals, conceals rocks and sticks and is easily tracked into schools. Safety surf was thought to be too expensive, and wood chips drained poorly.

Prince George's County. One of three materials -- mulch, wood chips or sand -- may be found on the 144 elementary school playgrounds, depending on which material was available when the ground was surfaced. For example, the county once used sand on its playgrounds, but because it washed away easily, the system began using wood chips when it built a new school or resurfaced an old playground. Later, it switched to mulch, but when the cost of mulch and wood chips became prohibitive, it went back to sand.

Alexandria. Playgrounds at the city's 12 elementary schools are positioned over beds of wood chips, sawdust or sod, said safety director Bill Blair.

Arlington. The 21 elementary school playgrounds are set over sand. "It's not the best," said Bob Gill, the physical education curriculum specialist for Arlington schools. He said the county tried safety surf but vandals ruined it easily. And wood chips were rejected because of the potential fires. "In dry weather, they could catch fire if someone on the playground tossed a cigarette on them," he said.

Falls Church. Both of the elementary schools in Falls Church have sawdust beneath the equipment.

In an attempt to reduce injuries, the U.S. Consumer Product Safety Commission developed standards for the manufacturing of back-yard swingsets and other at-home play accessories. But those rules don't extend to the equipment installed on public park and school playgrounds.

Now, after six years of study and consideration, the commission has put aside plans to develop safety requirements for the public playground equipment. Instead, the commissions plans to publish two handbooks on playground equipment and surface. The first volume will contain technical test results, mainly for those who design equipment and manufacture it. The second volume will focus on safety tips, how to buy equipment, how to retrofit existing equipment.

Both handbooks are scheduled to be published by the end of the year.