Q. My 10-year-old attends a private school, whose buses do not have seat belts. I tried to pursue the question of installing them, but the P-TA president said "they" advised against them.

I would like something more substantial than hearsay. What are the official positions of the traffic safety experts?

A. Actually, your P-TA president is basically correct and your child is a lot safer than you think. According to Joan Claybrook, president of Public Citizen, Inc., and former administrator of the National Highway Traffic Safety Administration, it's unwise to install them in buses that are used for all ages and sizes. Because of this, and because school children might not buckle the seat belts anyway, the NHTSA decided the seats should be designed better instead. Any buses manufactured after 1977 have seats engineered to cushion children in forward crashes.

Although Claybrook herself would prefer belts to be used, this is probably the most reasonable choice for multi-purpose buses, she said. In any case, a school bus is so much heavier it absorbs less energy in a crash, and therefore so do its passengers. About 35 children are killed in school buses each year, which is a very high figure if your child is one of them, but it's far, far less than the average, annual rate of 50,000 deaths in car accidents.

Because a school van is built differently, it must have a lap belt for each passenger -- with shoulder harnesses for the passengers in front -- to keep them from the windshield.

Q. I'm greatly concerned for my two granddaughters, age 9 and 5, and would like to find out if a dealer could install extra seat belts for a Chevrolet station wagon. Several have told me they could not.

A. Again, according to Claybrook: Cars, including station wagons, are required to have a lap belt for every regular seating position, which means about every 50 inches. If they're missing they can be added, but this will be very expensive if the car isn't designed with pre-drilled holes in the structure to accommodate them. However, if they've been removed for some reason, or never installed, the cost would be quite low.