The houses that Robert Firth builds look no different from the other modern wooden structures at Ocean Pines, a quiet, wooded community near Berlin, on Maryland's Eastern Shore. But with Firth, a customer can add some unusual options -- such as a workboat and fishing equipment, or freeze-dried dinner for two for a year. Or a bomb shelter.

He hasn't sold a bomb shelter house yet, but he's optimistic. "I got an awful lot of phone calls about them when the Russians invaded Afghanistan," Firth said.

The trouble, he said, is that people just don't want to put their pocketbooks where their anxieties are.

For people like Firth who think things are bad and will get much worse these are, in fact, boom times. Spurred by visions of Armageddon, these self-styled "survivalists" are stocking food and buying silver and gold, firm in the conviction that the future for the won't hold any surprises.

Although a fanatical fringe waits for a Soviet attack, the survivalists differ substantially from the folks during the Cold War who used to worry about sharing bomb shelters with neighbors.

Today's vision of the apocalyse is based more on economics, than atomic bombs. Its impetus was the Arab oil embargo in 1973-74 and the fear that Americans would soon be faced with scarcities in other raw materials and, eventually, in food.

The success of Howard Ruff's best-selling book, "How to Prosper During the Coming Bad Years," published in 1979, gave some legitmacy to the movement. In the book, Ruff advised investing in precious metals, storing food and buying and building homes outside cities as the best means of coping with the next decade.

While the numbers of survivalists is uncertain, the message is clearly being heard in the Washington area.

"About seven years ago I noticed I was instinctively doing survivalist things," said Raleigh Miller, a stockbroker in Gaithersburg who heads one of seven Ruff discussion groups in Montgomery County.

"I thought I was the kook before Ruuff came along and wrote about everything I had been doing all the while," she said.

Miller tells her clients to invest in harder assets, such as real estate, gold silver and diamonds.

"I'm not crazy, really I'm not," said Greg Welsh, an energy consultant who believes that a lack of energy will be America's downfall. "I just consider myself a realist." Welsh is experimenting with solar energy and wind power at a farm in Cantonsville. If he can supply his own energy, he believes he'll survive.

Most believe that doomsday will be an economic collapse that will make the Great Depression look like high times. Some await Judgment Day in the form of a cosmic cataclysm, while others expect an all-out Soviet attack or complete chaos in the cities.

Whatever their theory, they'll be prepared

They come to Firth, usually anonymously, as a builder of "survival homes" -- advertised as "tax shelters that can save your life" -- expecting the same confidentiality they would get from their psychiatrists.

They prefer anonymity for fear of what the neighbors might think, and do if they get hungry when the cities run out of food.

One person who inquired about Firth's selection of wood stoves, propane generators and bomb shelters wrote, "I have been concerned for some time about neclear war and similar catastrophes. At times I have felt I was the only person concerned about these things."

Firth has so far sold nine "survival houses," which he started building after reading Ruff's book last year, for an average of $69,000 apiece. A fully equipped -- complete with bomb shelter and emergency generator -- house costs $89,000 but so far he hasn't had any takers.

Although these houses are only a small portion of Firth's income -- he's sold more than a hundred "nonsurvival" houses in Ocean Pines -- he hopes that as times get worse, his business will get better.

Firth described his potential customers as "very well-read, in the upper middle-income bracket -- $50,000-$60,000 a year -- and slightly to the left of Attila the Hun. Actually, they're Republican, and a lot of them work for the government."

"I used to be a wide-eyed-liberal," said Milton Popeck, an accountant in Silver Spring. "But I really have turned conservative. Once I got involved in survivalism, I was much more careful with my investments. I wouldn't build a bomb shelter, but I would buy diamonds and rental property in the country."

Mel Tappan, a hard-line survivalist in Oregon whose starter survival kit includes an assortment of shotguns, hunting rifles and automatics, said that more than half of those in the Washington area who subscribe to his 17,000-circulation "Personal Survival" newsletter are government employes or "investment types." the rest, he said, are psychiatrists.

However survivalists differ, most seem to share the belief that they will emerge from the ashes only if they are in the country.

"The location is very important," said Jim Lambertini, who recently moved from Baltimore to a waterfront survival house in Ocean Pines. "If we run out of food, or if the farmers won't take our money, we've got water full of crabs and fish right outside our door. I know where to get everything I need, and we can get almost everywhere by water."

Lambertini, a 59-year-old retired Army colonel, already has a full freezer of fish, strawberries, TV dinners and vegetables.

He and his wife, Emma, are currently tast-testing freeze-dried beef stronganoff. "It's really not that bad," he said. He hopes that doomsday doesn't come down to a continuous diet of the stuff, but, he said, "I think the country will be in awful shape come the next few years -- either because of nuclear problems or economic collapse.

"We'll be in good shape as long as we have enough food. We're prepared. I don't expect anyone to come after me for my tomatoes or crabs, but I can't see shooting anyone if they try to take some of my food."

If it does come to that, though, "We can always close off the Bay Bridge before they storm the Delmarva Penisula for the food supply."

Stockbroker Miller, who's "personally petrified of electricty," said, "I've been storing food for years and recently I've been buying gold. Now I feel I've got a jump on others who aren't prepared."

Where a nonsurvivalist might buy a few extra cans of coffee when it's on sale, Miller said she filled her grocery cart with coffee before the prices went up about four years ago. It's not being miserly, she said. It's just being prepared.

Miller's version of gloom is the so-called Jupiter Effect, when the planets, will line up with the sun, triggering violent earthquakes, storms and hurricanes. To Miller, there are already signs. "The weather is just getting worse and worse and worse. They had an earthquake in Kentucky; this is unheard of. And Mount St. Helen's is just going crazy."

Jeff Cohen, a Silver Spring resident and leader of the Ruff discussion group there, considers himself a true servivalist. "I own Key Bridge Exxon, and if I pull through this D.C. gas tax okay, somehow I'll survive. e

"But we're not all doom and gloom," Cohen continued. "We just believe in the eventual, inevitable collapse of the dollar and the economic system. I am personally interested in putting my money into hard assets -- gold, silver -- but I haven't gotten to the point of buying land out in the country. That'll come next."

"We're going to be caught with our pants down," Welsh, the energy consultant, asserted. "What's happening now is a slow gradation process. It's like putting a frog in a pot of boiling water. He'll jump out. But if you put him in the pot, and slowly turn up the heat, he'll gradually boil to death.

"That's what's happening to us. Things are gradually getting worse and worse, so we don't really notice what's happening. Whatever happens will happen slowly, and we won't have time to jump out."

Survivalists don't expect the sky to fall in the near future. They point to 1982 or 1983 as good years for the bad times, believing that's when the Jupiter Effect will have its impact.

And if nothing catastrophic occurs, they believe, as Milton Popeck said, "Heads we win, tails we break even."