The National Occupant Protection Use Survey says that the number of people observed during a study conducted earlier this year rose by a percentage point over last year's results.

Researchers at NOPUS, the official tool used by the National Highway Traffic Safety Administration to provide a probability-based observational survey of seat belt use in the United States, found that 85 percent of drivers were wearing their seat belts, up from 84 percent observed last year. Meanwhile, 84 percent of passengers were observed wearing their seat belts, also up a percent from 2008.

The percentage of occupants wearing seat belts in the 26 states and the District of Columbia with primary enforcement laws remained the same at 88 percent, but those wearing seat belts in states with secondary or no seat belt enforcement rose to 77 percent from 75 percent last year.

The groups that saw declines in seat belt usage were occupants on expressways (1 percent decrease to 89 percent), vehicles traveling in heavy traffic (5 percent decrease to 92 percent) and slow traffic (1 percent decrease to 78 percent), occupants traveling in slow traffic (1 percent decrease to 78 percent), those in urban areas (1 percent drop to 83 percent), and those in light fog (2 percent decrease to 78 percent

The NOPUS survey was conducted from June 2 through June 22, between the hours of 7 a.m. and 6 p.m. It observed a total of 100,000 vehicles with 127,000 occupants (drivers and front passengers only) at 1,823 sites across the country.

Starting in Fall 2011, all newly manufactured small school buses will be required to have three-point lap shoulder belt restraints similar to those in passenger vehicles. Large school buses won't be required to have them, but NHTSA published recommendations for installing them at the manufacturer level should individual states or school districts decide to provide them to students.

Currently, only California has a law in place that requires the seat belts for all school buses. Laws in Florida, Louisiana, New Jersey and New York only address two-point lap belts in school buses. Texas passed a law that would require three-point systems in school buses, but it would only go into effect if the state legislature can appropriate the necessary funding, a stipulation it has yet to be successful in enacting.