A new law requiring drivers and front-seat passengers of motor vehicles to wear seat belts while riding in the District is now in effect, according to a reminder issued yesterday by the office of Mayor Marion Barry.

D.C. police will not issue tickets to violators for six months, however. The seat belt law, which became effective Dec. 12, specified that a public education program be conducted before officers start making arrests for violations.

In January, the Department of Public Works will begin an education campaign aimed at explaining the law and its goals, according to a spokeswoman for the agency. The program, to be conducted in the media and in schools, will be part of a larger safety program focusing on seat belts, car seats and the problem of drinking and driving.

The seat belt legislation, signed by Barry in October, provides for a $15 fine for anyone charged with a violation. Under the law, police officers would be able to issue tickets for seat belt violations only after they have stopped motorists for some other offense.

Initially, the seat belt bill had exempted taxicabs, ambulances and vehicles used for sightseeing, funerals and farm purposes. However, the council amended the legislation so that only farm vehicles would be exempt.

Mandatory seat belt legislation was spurned by Maryland and Virginia lawmakers last year, but the issue is expected to come before the states' legislatures again this year. Earlier this month, the Fairfax County Board of Supervisors called on the Virginia General Assembly to adopt a mandatory seat belt law.

At least 16 states have passed mandatory seat belt laws.

The D.C. seat belt provision is the second law related to passenger restraint passed by the council. Since 1982, children under 6 years old have been required to wear seat belts or ride in safety seats.

"The Department of Public Works has managed an infant and toddler seat rental program since 1981," Kathy Williams, deputy press secretary to Barry, said in a statement. "Nearly 6,000 D.C. children have been placed in safety seats through the program."