Bert Simson and Dave Parrish are federal regulators. They work in the offices of the Consumer Product Safety Commission, in a leased apartment building in Bethesda, amidst functional government-issue surroundings.

Meanwhile, in an elegant office on K Street downtown, surrounded by antiques, fine art, and Oriental rugs, Mac Dunaway, a 36-year-old lawyer from the town of Bascom, Fla., who looks a little like H. L. Mencken, watches them like a hawk.

If you spend your Saturday afternoons behind a power lawn mower, the work of these three obscure men will affect your life. They're fighting, in the restrained way of regulators and lawyers, over the future of the central mechanism of suburban culture, the lawn mower.

Simson, Parrish and Dunaway are working on power lawn mower safety regulation which -- and this is one of the few things they agree on -- will one day cost the lawn mowing public about $190 million a year.

It will cost that much, that is, if it happens at all.

The Consumer Product Safety Commission began working on lawn mower regulation back in August 1973, just a few months after it went into business. That was when Mac Dunaway's client, the Outdoor Power Electric Institute, knowing the commission was casting its eyes on lawn mowers, asked the commission to adopt the industry's own voluntary set of safety standards as mandatory.

The commission said no, and in 1974 it gave Consumers Union, the organization that publishes Consumer Reports, a contract to develop the standards. In 1975 CU submitted its standards to the commission, which then spent two years checking them out and published them for public comment in 1977.

That was when Bert Simson, 53, a gray-bearded emigre from Germany and Israel who is director of the commission's Office of Program Management, and Dave Parrish, a 35-year-old GS13 who is a product manager in the commission's power equipment program, came into the lawn mower picture.

On Saturday both men pushed lawn mowers. During the week they presided over lawyers, economists, engineers, and technicians who examine lawn mowers out at a lab in Gaithersburg. They oversaw oral presentations, public meetings, and comment periods, debated such issues as foot-probe requirements and thrown-object tests, and finally, in early 1979, having accumulated 35,000 pages of official record on the subject, reached a decision.

They decided to require that walk-behind power mowers have a clutch device that means that the blade will stop moving three seconds after the operator takes his hand off the handle. There are a couple of other requirements, but the three-second rule is the most important. The commission says it will stop 60,000 injuries a year.

As soon as the commission published these requirements, Dunaway sued on behalf of the Outdoor Power Electric Institute, challenging the commission's figures, the three-second rule, the commission's "obsession" with the clutch device, and virtually every other aspect of the proposed standards.

Then the two sides had what's known as a "race to the circuits" -- the commission wanted the case to be heard in the liberal D.C. Circuit of the federal appeals court. Dunaway wanted it argued before the more conservative Fifth Circuit, which is headquartered in New Orleans. Dunaway won, but the question of venue took six more months to settle.

Finally, last April 1, nearly seven years after the Consumer Product Safety Commission began trying to regulate lawn mowers, a three-judge panel in New Orleans heard the case. That took about an hour. The judges are now considering their decision -- which may very well, of course, be appealed.

Sad to say, this saga is fairly typical of the way federal regulation works -- or, to put it more accurately, doesn't work.

It's typical in two ways: first, that it has taken so absurdly long; and second, that, as has been the case with every set of safety standards the Consumer Product Safety Commission has ever produced, the real regulation makers will be not the Congress or the president or even the commission, but federal judges.

The reason for that goes back to the commission's founding in 1972, under conditions typical for regulatory agencies.

Congress, not wanting to take on the bother or the controversy of regulating products on its own, in effect passed the buck to unelected officials. It gave the commission a mandate "to protect the public against unreasonable risks of injury associated with consumer products" -- not a very tough sentiment to vote for, especially considering that the most dangerous and controversial of consumer products, cigarettes and cars, were specifically exempted from the commission's reach.

Like most agencies given vague missions to do good, the commission was also told to operate under the dictates of the Administrative Procedure Act of 1946, which makes agencies function in quasilegal ways and makes their decisions appealable to the courts.

That's why the commission's first three major sets of safety standards -- for swimming pool slides, matchbooks, and architectural glass -- took an average of 834 days to develop. And it's why anything the commission does that is controversial is virtually guaranteed to end up in court, so that its most important regulatory decisions are really made by judges.

There's a cartoon on the wall in Simson's office, a parody of the regulatory process that's popular around the commission. It has eight panels, and charts the mythical course of tree-swing regulation.

In the first panel there is a tree with a wooden swing hanging from its branch. The swing goes through various permutations until, in the last panel, representing the issuing of final standards, it has become a tire hanging from the branch instead.

Lately the cartoon has been amended. Somebody has stuck on a ninth panel at the end, entitled, "When the courts finally ruled on it."

It shows the same tree -- but with no swing at all.