Twenty-two million American children ride buses to school every day, but fewer than 200,000 -- living in 24 school districts scattered around the country -- are required to wear seat belts. Yet figures for the 1982-83 academic year (the most recent available) reveal that 13 students were killed and approximately 1,500 were injured in school bus accidents.

These figures may not be staggering, but bus injuries are almost wholly preventable by the proven and inexpensive seat belt. Forty-nine states (Wyoming is the lone exception) and the District require all children up to at least 6 years old to be restrained with seat belts when riding in an automobile. However, when these same children board their school buses, they can forget about seat belts.

Dr. Robert A. Burns, a Dalton, Ga., surgeon and regional coordinator for the National Coalition for Seat Belts on School Buses, thinks this "is not only terribly inconsistent and confusing to school children, it's also very dangerous." I agree with Dr. Burns.

Since 1977, seat belts have been mandatory on small buses carrying up to 16 passengers, but the standard 66-passenger school bus has escaped this requirement, despite findings from the National Transportation Safety Board that "fatalities and injuries to school children on buses are caused in large part by the absence of occupant restraints."

Tests have repeatedly demonstrated the value of seat belts in substantially reducing traffic injuries, and both the American Medical Association and the American Academy of Pediatrics have stated that the belts prevent or significantly decrease serious head, spinal and extremity injuries in rollovers and lateral collisions.

And while several states have enacted mandatory seat belt laws for cars, none has one for school buses. Citizens in communities as varied as Skokie, Ill., Hartland, Vt., and Klamath, Ore., are working to change that.

In suburban New York's Westchester County, parents whose children attend school in Greenburgh Central School District 7 succeeded in mandating use of seat belts on buses in 1979. Since then, use of the belts has hovered around 80 percent. In the district's most recent school bus accident, in January, the bus driver, school officials and the children themselves credited the seat belts with saving them from serious injury.

Some may be tempted to write off seat belts for school buses because "only" 13 children were killed in bus accidents in the 1982-83 year, which is less than 0.03 percent of all traffic fatalities nationwide. But seat belts on buses would decrease the fatalities to virtually none, and the number of injuries, especially the more serious ones caused when the buses roll over, to fewer than 50 in any given year.

If the use of seat belts in automobiles greatly reduces traffic fatalities and serious injuries -- though fewer than 15 percent of Americans actually buckle up -- then compliance of 80 percent or more on school buses would reduce fatalities and serious injuries tremendously.

And there is no question that the limited but growing use of seat belts in automobiles has significantly decreased traffic deaths. Recently, for example, Virginia Del. J. Samuel Glasscock unsuccessfully tried to persuade his state legislature to join the mandatory seat belt club. He cited some convincing statistics. In the most recently tallied 12-month period, from July 1, 1982, to June 30, 1983, 1,352 people not wearing seat belts were killed in automobiles on Virginia's highways. By contrast, only 35 fatalities occurred among seat belt users. While most of Glasscock's colleagues agreed that seat belts saved lives, they nevertheless felt government should not make their use compulsory.

In the case of school buses, though, we are talking about children. Lawmakers have no problem imposing minimum drinking ages on young people. Why, then, is it an infringement on individual freedom for responsible adults to require seat belts for school children?

Some critics maintain that seat belts would hinder emergency evacuation of school buses. Nonsense. As Burns, the Georgia surgeon, concludes, "Serious injuries resulting from students not being properly secure in their seats during collisions are the biggest deterrent to safe, efficient and speedy evacuation."

Two Democratic congressmen, Peter Kostmayer of Pennsylvania and Larry Smith of Florida, have introduced legislation calling for mandatory installation of seat belts on new buses. Kostmayer's plan provides for financial aid to school districts -- a pool totaling up to $10 million annually for three years to help defray the costs of installing the belts. Smith's bill threatens to withhold federal funds from any school district that does not install seat belts on buses.

With states beginning to pay serious attention to compelling their drivers to buckle up, it is only a matter of time before compulsory school bus seat belt legislation is passed. Even opponents of such measures concede that it is inconsistent to force people to buckle up in their cars but allow their children to ride buses unprotected. "On that basis," says National Highway Traffic Safety Administration chief Diane K. Steed, "we are looking seriously into requiring them."