Few regulations exist to prevent a preschool child's frolic on playground equipment from turning into a potentially fatal fall, even though many such hazards could be avoided, federal health officials say.

The Centers for Disease Control said Thursday that workers at construction sites are protected by more safety precautions than children under 4 years of age on playgrounds.A child could suffer severe head injuries or die if he fell headfirst onto a concrete or asphalt surface from a height of 1 foot or onto packed earth from 4 feet, the CDC said in its weekly report.

"If you can crack your skull from a fall from 1 foot off the ground, why put concrete on the playground?" asked CDC epidemiologist Jeffrey Sacks. "We're not asking a child to change his behavior, we're just saying make the environment more forgiving."

A 4- to 5-foot fall can be fatal for an adult, and the Occupational Safety and Health Administration requires that guardrails be installed in some instances to protect workers as low as 4 feet above ground, Sacks said.

Yet no regulation exists requiring safety measures to guard against playground falls.

Although the Consumer Product Safety Commission supervises the equipment, Sacks said, it does not control where it is placed. The CDC's report said 48 percent of day-care playground equipment is not installed over impact-absorbing surfaces.

"The CPSC regulation doesn't stop anybody from taking safe equipment and mounting it over broken glass," Sacks said. "And there's no regulation regarding that."

The CDC said the severity of injuries is reduced if a child falls from as high as 8 feet onto energy-absorbing mats, wood chips or sand.

The agency recommended that playground equipment be made safer for small children by installing it over soft surfaces, locating it away from obstructing objects, anchoring it and inspecting it frequently. If wood chips or sand are used as surfacing, they should not be allowed to compact or fall below an adequate depth.

Most preschool-aged children with injuries involving school playground equipment were 3- or 4-year-old boys, with more injuries occurring in the spring months, the CDC said.

According to data gathered by the CPSC, about 6.2 million emergency room visits in U.S. hospitals between 1983 and 1987 were product-related injuries among preschoolers aged 1-4, with 305,281 involving playground equipment.