More than 375,000 skateboard-related injuries are expected to occur this year, double the number in 1976, according to a Consumer Product Safety Commission study to be released next month.

The figure estimated for this year is based on information gathered during the first half of 1977 by the commission, and represents "the largest increase in frequency of injury of any product that the commission has jurisdiction over this year," according to William Kitzes, commission program manager for sports and recreation.

Skateboard injuries are expected to surpass football injuries for the first time, and are now second only to bicycle-related mishaps. But Kitzes points out that threr are approximately 20 million skateboardes, compared with about 80 million bicycle users.

About 40 per cent of the skateboard injuries result in hospital emergency room treatment. Kitzes said, with 30 per cent of those resulting in fractures of the lower arm and lower legs. Contusions and abrasions account for 24 per cent of the hospital injuries, while strains and sprains make up 18 per cent of the mishaps.

Injuries to the head and face account for 15 per cent of all in juries. Kitzes added. "We also get a lot of permanent abrasions on knees," he said, "something we call skate-boarder's knee. The serious lise in all of these injuries leads us to again strongly recommend the wearing of sucr protective equipment as helmets, knee pads and hip pads."

The study reveals that the boards are comparatively safe, with only 2 per cent of all injuries directly tied to product-related defects.

Most of the injuries, according to Kitzes, are caused by the inexperience of the skater or problems with the riding surface.

More than 25 per cent of all accidents occur the first day a rider uses a skateboard. Kitzes said. An additional 12 per cent come in the first week of use.

Thirty-five per cent of all injuries are the result of "striking irregularities in the riding surface," like potholes in the street, Kitzes said, "which would indicate that a controlled environment could result in fewer injuries."

The report is expected to be a boon for promoters who have built private "skateboard parks" and have encountered some difficulty getting liability insurance. The study indicates that if the skater uses a proper riding surface, the risk of injury is significantly lowered.

But Kitzes said that agency officials will in the coming weeks, approach the Department of the Interior to see if funding can be made available to turn existing parklands around the nation into federally run skateboard parks.

The study indicates, also, that a skater is better off using his or her own board as often as possible. It shows that 39 per cent of all accidents occur on a borrowed skateboard, indicating that experience on the board can be a factor in considering the injury possibilities.

"What is obviously important is the feel of your own board and its capabilities," said Kitzes. "Human factors are shown to be the most important causes of accidents. The skating environment is a close second."

According to the report, 45 per cent of all skaters are in the 10-to-24-year-old age group.

The study, undertaken in May, marks the first time the federal agency has calculated skateboard-related accidents.

The data will be used by staff to formulate recommendations for commission action - including the possible use of federal land for skateboard parks.

Commission sources ndicated that the report was in no way a government endorsement of the privately run skateboard parks, but admitted that, at this time, the parks are safer than the streets for skateboard use.