After listening to almost four hours of heated testimony, the Fairfax City Council last weerk postponed a decision to realign the city fire department. The council now is expected to take up the matter at its meeting Tuesday.

The delay avoided further inflammation of relations between the paid and volunteer firefighters, which have been smoldering for more than a year.

The council has been expected to reorganize the department by giving the chief of the volunteers, Charles Seay, ultimate authoity over the 74 volunteer and 37 paid firefighters. At present, the volunteer chief is commander at the scene of a fire, while the paid director of fire and rescue services, Joseph R. Gegauer, commands day-to-day station operations.

By a 4-3 vote last month, the council decided to change that arrangement after volunteers complained that the chain of command was confusing. The volunteers' suggested solution was to place one person, the volunteer chief, in charge of all operations. The council was expected to make that change and create a new office of fire marshall last week.

But testimony by paid firefighters and citizens opposed to the plan continued until nearly midnight, and the council agreed to delay action on the proposal.

Last week's hearing was the latest attempt to cool a situation that has been producing sparks since May 1978, when City Manager George Hubler, with the City Council's approval, organized a paid Department of Fire and Rescue Services to augment the 52-year-old volunteer department.

Hubler's action which came after the city ended its mutual protction contract with Fairfax County, has been subject to different interpretations.

The volunteers have accused Huber of trying to "run us out of town." Al Adams, president of the volunteers, said in August that Hubler was trying to make his resume look good by creating the impression he had cleared the city of its "beer-drinking, checkerplaying, redneck volunteer force for an effective, modern paid force."

The paid firefighters argued that the city needs a "professional" chief to command a modern department. They accuse the city council majority, including Major Frederick W. Silverthorne, of being less concerned with creating a first-class fire department than with caving in to the demands of the volunteers to save the city money.

Mark Kane, a paid firefighter, said last week the issue had become "much too political" and worried that the council majority was "playing havoc with the public safety."

Another speaker, Mary Ellen Kelly, called the council plans to reorganize the fire department "appeasement on a grand scale." Kelly added, "We are being bullied by a few vocal firemen and the fear of a tax increase."

Major Silverthorne conceded hat financial considerations were a factor in his vote for the volunteer position. The volunteers, and Silverthorne, legally own one of the city's two fire stations and all the fire-fighting equipment.

"If we had to duplicate what the volunteers offer us for nothing, the capital cost alone would amount to $1.5 million."

Councilman Glenn White, who voted last month for a volunteer-led department, said after discussions with volunteers, he felt "very strongly if we do establish a paid chief . . . we can kiss the volunteers goodbye."

Kenyon Pease, chairman of the Fairfax Jaycees' board, presented a petition to the council with 1,846 signatures calling for the council to reverse its October vote. Pease said putting a volunteer chief in charge of the department could result in "catastrophic consequences."

Edward C. Weiss told the council he was "puzzled" by its decision to reorganize the department. "If you told me the volunteers represent a large block of voters which will affect the next election, I'd find that understandable." Otherwise, said Weiss, "it makes about" as much sense to put a volunteer in charge of a fire department as it does to put the commander of the national guard in charge of the Army."

Silverthorne countered that naming a volunteer chief is "not new or revolutionary" and cited the examples of Falls Church and Vienna, where a volunteer chief ranks above a paid fire service administrator.

"Don't believe the malarky that the volunteers are not professionals. Our volunteers have been fighting fires successfully for 52 years."

Council member Susanne Max, who voted against placing the volunteer chief in command, praised the volunteer department for its half century of service, but added that the city had outgrown an entirely volunteer force.

"I'm much more interested in the future history of this city than I am in the past," said Marx, adding that the commerical value of city property, which has risen above $538 million, demands that the city have a paid chief who is accountable first to the city and not an independent oranization such at the volunteers.

In the recent months, the relationship between the paid and volunteer firefighters has been less than harmonious. Last Summer the volunteers complained that paid firefightersput fishhooks in their coat pockets and scrawled obscenities on their helmets. Volunteers say that type of harassment has stopped, but they describe the current situation as an "uneasy peace."

"We can do the job and we've proved we can do it. But not when they (paid firefighters) are determined to make it so we can't work," said volunteer chief Seay during a break in last week's meeting.

Whatever decision the council makes it is expected to fan a situation that is now smoldering.

"Firefighting is the most dangerous job in the country," paid firefighter Gregory Valcourt told the council last week. "You don't have to work for somebody not qualified. I do. And I won't."