Starting in January, federal workers who moonlight as occasional writers, critics or lecturers may have to stop taking pay or gifts for their services or face fines of up to $10,000.

The honoraria ban would hit the Washington area hard. Many of the 360,000 federal workers here sometimes write for newspapers, magazines or trade and hobby journals about subjects that have nothing to do with their official jobs. Some do political or historical articles, or write dining or wine columns. Others are sought after as paid speakers on subjects ranging from gardening to the Civil War, or work from time to time as radio or TV consultants on subjects unrelated to their jobs. Workers who have regular outside employment contracts apparently would not be affected by the honoraria ban.

Executive branch employees have long been barred from taking money or gifts from outside groups for speaking or writing about their work-related expertise. But the tough new ban, part of the Ethics Reform Act of 1989 aimed at congressional honoraria, also zeros in on rank-and-file federal workers.

It would, for example, prevent a Labor Department economist from writing an article for pay about cooking or oriental rugs, and make it a civil penalty for a NASA rocket scientist to give a lecture about dinosaurs for a fee or gift. It also would cover such people as part-time doctors with the Department of Veterans Affairs who are paid to lecture.

The act bars members of Congress from taking honoraria from special interest groups for articles and speeches, giving them in return a two-stage pay raise. The second raise, a 25 percent increase due in January, will increase members' pay from $98,000 to about $125,000 a year. Federal workers are scheduled to get a much smaller raise in January.

Because the honoraria ban is tied to the congressional pay raises, members of the House and Senate have been reluctant to bring up the issue before the elections. As this session wound down, the Senate Governmental Affairs Committee was quietly working on language to ease the honoraria rules for rank-and-file workers. The plan was to add it as a rider to an unrelated bill concerning the naming of a post office, to get it moved quietly and quickly through Congress. If that effort fails, it will be next year -- after the rules take effect -- before efforts will be made to relax them.

The new law says: "No representative or officer or employee of the government may receive honorarium which is defined as any money or thing of value for any speech, appearance, or writing, excluding travel expenses. There is no exception for speeches, appearances or writings on matters that are totally unrelated to one's government job."

Government legal experts say the ban doesn't cover people with contracts to write or lecture on a regular basis. Nor would it apply to people who write books where the earnings are based on royalties. But the new rules will affect many federal moonlighters, unless Congress can find a way to get them off the hook without calling unwanted attention to the congressional pay raise issue.