Like a policeman or a fireman, Richard Swanson long ago became accustomed to emergencies and organized his office to control the hurricane of telephone calls and headlines and fear they bring.

But this fall's succession of storms -- Tylenol, Lavoris, Excedrin -- have given the Food and Drug Administration's emergency operations office an extraordinary battering.

In that 13th floor office, 50 square feet jammed with desks and charts and a few computer screens, six telephone lines have demanded constant attention. FDA employes throughout the Parklawn Building in Rockville repeatedly have been deputized to help the 11 staffers who have worked marathon hours since the first revelation that someone had filled Tylenol capsules with cyanide and killed seven people in Chicago.

The office is in business year-round. But, Swanson said, "we're working some round-the-clocks through the Tylenol operation. During the Tylenol situation we worked one continuous week and through the holiday Columbus Day weekend."

After that, things were comparatively relaxed, he said--until the report of adulterated mouthwash brought a new crescendo of telephone bells. Another lull; then this week's news of Excedrin capsules apparently tainted with mercuric chloride that led to at least two hospitalizations. "It's been continuous activity but it has peaks and valleys," Swanson said this week. "Right now it's at a peak. The telephone mode is intense and doesn't stop."

Swanson, 50, serves as director of FDA's Emergency and Epidemiological Operations Branch, the central control and reporting office for the agency's 23 field offices and for 129 one-person "resident posts."

"Basically the complaints we would receive are illness-injury type of complaints," Swanson said. "We would formulate multiple hypotheses of what could be wrong. We're trying to associate a disease syndrome with a particular product. We check the onset time and symptomatology and see what kind of illness we have going."

"We," in this case, includes a computer specialist, two food scientists, and several other investigators and support staffers. Swanson has been doing this sort of medical detective work for 20 years, starting as a state investigator in Detroit, where he helped track a botulism outbreak to a batch of smoked whitefish.

"Most of us have backgrounds in food science and microbiology . . . We have to know how a product is processed and what processes could break down, to relate whether an illness could be caused by a product."

Among their tools is a computer programmed to compare the data coming in on scores of complaint forms -- information on the size of a product package, its lot number and, in the case of drugs, whether it's a tablet or capsule or liquid. They then alert FDA emergency workers to patterns that could pinpoint a dangerous product.

And if a potentially poisonous product is found, it is Swanson's people in Rockville who coordinate the whole process of a recall.

Swanson's office, by the way, is also ready for other kinds of emergencies. His office will direct what FDA employes are supposed to do in the event of a nuclear war.