Washington area real estate appraisers, like those in the rest of the country, soon will be hitting the books and cramming for exams as they seek official accreditation for the first time.

One by one, state legislative bodies are complying with a federal mandate to clean up and professionalize the appraisal industry. Under the 1989 savings and loan rescue bill, states were directed to establish local appraisal governing boards and, for the first time, set educational and experience guidelines that will require appraisers to qualify for professional status, similar to the process for accountants and lawyers. The local systems must be in place by July 1991.

Despite their crucial importance as arbiters in real estate transactions, appraisers until now have been virtually unregulated with no specific professional standards or guidelines. Lax appraisal standards have been a key factor contributing to the collapse of hundreds of banks and savings and loan institutions, with a combined loss to American taxpayers of at least $500 billion.

The D.C. Council last week passed emergency legislation to require appraisers to attend educational and ethics courses, pass exams and apply for professional licenses. Under the legislation, which creates a two-tiered system of "licensed" and "certified" appraisers, those who break the rules can lose their right to play a role in transactions involving federally insured financial institutions.

"The District can look forward to fair, equitable and professional appraisals from people who are competent," said Michael F. Taylor, administrator of the District's occupational and professional licensing administration. "We're putting people on notice that an appraisal means something."

Maryland and Virginia both passed appraisal legislation months ago, but both measures may need to be redrafted because they fail to meet federal requirements.

Under the federal legislation, even appraisers who have been working in the field for years will have to meet established experience and educational standards and pass exams. Some longtime appraisers say they are feeling a little jittery at the prospect.

"Many of the old-timers have not been to school for a while, and it's frightening," said Sarah Lyon, a real estate appraiser employed by the District who has been active in establishing the local appraisal-regulation program.

"Even I'm worried about taking the exam," she said. "Who isn't? There's the fear of losing your livelihood. But it makes you scramble to study harder to make sure you pass it."

But for Lyon, passage of the appraisal legislation has particular personal significance. Lyon formerly worked for the Department of Housing and Urban Development, where she helped uncover a pattern of faulty real estate appraisals in the District that has cost the government at least $10 million.

The new appraisal requirements, Lyon said, put local appraisers on notice that they are accountable for their work. "Now they have to show they have knowledge, and that they can use it, or they risk losing their licenses," Lyon said.

Supporters of the legislation hope it will also help change the nation's banking industry. Through the 1980s, faulty or fraudulent real estate appraisals were a primary tool used by people who defrauded financial institutions by engaging in land purchases and quick resales and other unsafe real estate loan practices. A 1989 General Accounting Office study found faulty appraisals were used at nearly all of a sample of 26 failed S&Ls it probed.

In general, the licensure and certification process is proceeding smoothly around the country, according to interviews with appraisers and a recent report by the House Committee on Government Operations. About 42 jurisdictions have drafted appraisal legislation of some kind, and about 35 of those laws have been reviewed by federal regulators.

Several thorny problems remain, however. Some states rushed to comply with the federal law, passing legislation before the federal organization created to monitor their efforts, the Appraisal Subcommittee, was fully organized. Consequently, some states, including Maryland and Virginia, passed laws that apparently do not fully comply with the federal law as it is now being interpreted, and they may need to go back and do it all over.

Virginia, for example, created a three-tier system, establishing "licensed," "certified" and "general" categories of appraisers. Licensed residential appraisers are allowed to do appraisals of houses and small apartment buildings with no more than four units and worth less than $1 million. Certified appraisers are permitted to do more complex and expensive residential appraisals, while the the general category covers all kinds of appraisals, including those of investment and commercial properties such as office buildings and shopping centers.

The Appraisal Subcommittee, however, has endorsed a two-tier system that separates licensure, which allows small residential transactions, from certification, involving larger transactions.

Maryland was informed by letter in September that its legislation failed to pass muster. Its three-tier system permitted some grandfathering of existing experienced appraisers and waived the educational requirements if an appraiser could show "good cause" for being unable to meet them.

A few states passed legislation containing clear and apparent conflicts of interest, according to industry experts including David Bunton, executive vice president of the Appraisal Foundation, a nonprofit group that sets appraisal standards. Florida and Texas, in particular, passed laws that require appraisers to first become licensed real estate salespeople.

Ironically, those are two states that will cost American taxpayers dearly because of real estate-related losses emanating from the widespread collapse of the savings and loan industries there. Both states are likely to be required to amend their legislation, according to those involved in implementing the federal regulations.