ONE BY ONE, Leonard Ragland identified the bodies of his family. "This is my mother. This is my father," he said as the white sheets were lifted. Then he identified the woman he was to marry the next day.

In all, seven persons had died in the fire at Ragland's home in McLean. Investigators said the fire, the worst residential fire in Fairfax County history, had been started by a cigarette left burning in an over-stuffed chair in the basement. It could easily have been prevented had tobacco companies used patented processes, available for a number of years, which cause cigarettes to extinguish themselves when not being smoked.

An estimated 70,000 smoking-related fires occur each year in America, according to the U.S. Fire Adminstration, a federal agency which provides training and education programs to local fire departments. Every year, those fires result in more than 1,800 deaths, 4,000 injuries and $180 million in property losses. More than a third of all Americans will die from smoking-related fires.

These deaths, like those of Leonard Ragland's family, could easily be prevented.

Scentific studies have found that a freshly lit cigarette will burn for more than 20 minutes without being puffed. After 10 or 15 minutes, a lit cigaette dropped into a piece of upholstered furniture will usually start to smolder and start a fire.

Patents for developing cigarettes that would self-extinguish after several minutes of not being puffed have been inexistance for more than 50 years. But the tobacco companies have refused to manufacture self-extinguishing cigarettes. And every time legislation has been proposed in Congress that would require tobacco companies to make such cigarettes, it has been voted down.

In the 1920s, the late Rep. Edith Nourse introduced a bill to require cigarettes to be self-extinguishing. Although she introduced the bill in several successive sessions of Congress, it never was passed.

In 1975, the late Sen. Philip Hart introduced similar legislation which was passed in the Senate, but was overwhelmingly defeated in the House. The Tobacco Institute, a lobbying and trade association for the tobacco companies, waged an intensive lobbying effort against Hart's bill.

Most recently, bills have been introducd by Reps. Andrew Jabobs (D-Ind.), Joseph Moakley (D-Mass.), and Sen. Alan Cranston (D-Calif.).

Jacobs' bill would prohibit any substance from being added to a cigarette that would aid its burgning. Moakley's and Cranston's would give the Consumer Product Safety Commission power to regulate the safety of cigarettes and possibly require that they be self-extinguishing.

Sources on Capitol Hill give all three bills little chance of passage. "The Tobacco Institute is just too powerful," says one congressional aide. "They've given dozens of members of Congress campaign contributions and honoraria. People around here don't forget where the money comes from."

Joy Jacobson, an aide to Cranston, concedes, "This year our bill has very little chance of passage." According to Jacobson, Cranston met with representatives of the Tobacco Institute and Philip Morris and was told that "manufacturing self-extinguishing cigarettes would be a relatively easy thing to start doing."

But the Tobacco Institute decided to oppose all three bills. "By admitting that they could simply resolve the problem," says Jacobson, "they would be opening themselves up to liability cases and lawsuits from people who have been injured in cigarette fires. In some cases, the awards could be trememdous."

A Tobacco Institute spokesman, Walker Merryman, says the trade association has several reasons for opposing these bills.

"One thing you have to keep in mind," says Merryman, " is that these cigarette fires don't occur in a vacuum. As many as half of those fires happen when an excessive amount of alcohol and/or drugs has been used."

"The person who accidentially sets the fire," retorts David Pittle, a member of the Consumer Product Safety Commission who has fought for the cause of the self-extinguishing cigarette, "is not always the only person killed. Often times it is little children or older people in the next room who are killed. They're the ones least likely to escape."

Adds a D.C. fire official: "In the Fairfax fire, only one person left the burning cigarette on the chair. But six other people died.

"I've seen this type of fire from first-hand experience. We'll find the children lying dead on their beds. Most of the time they don't even wake up. They just die in their sleep."

Another reason that the Tobacco Institute and the companies it represents oppose such legislation, according to Merryman, "is that the technology available right now is not commericially or financially feasible.

"They've developed technology which will cause cigarettes to self-extinguish. But at the same time, the output of tar, nicotine and carbon monoxide would increase.

"We might cut down on an insignificant number of people dying in fires. But at the same time we would be increasing the number of people who would contract lung and heart disease due to the increased tar and nicotine."

Critics of the Tobacco Institute pooint out, however, that Moakley's bill would bar any increase in tar, nicotine or carbon monoxide levels in self-extinguishing cigarettes.

One patented process for a self-extinguishing cigarette even reduces tar, nicotine and carbon monoxide. Charles Cohn of Atlantic City says his process makes cigarettes self-extinguishing by adding sodium silicate to the cigarette paper. A Department of Health, Education and Welfare study found that cigarettes produced by Cohn's method would give off up to 25 percent less tar, nicotine and carbon monoxide per puff to the smoker. The HEW study also found that Cohn's process would cause cigarettes to give off 60 percent less tar, nicotine and carbon monoxide into the air while not being puffed.

A major American tobacco company also tested Cohn's process and confirmed HEW's findings.

"The company didn't want to use my process, though," says Cohn. "They said they have their own research departments to do things like this."

Tobacco Institute spokesman Merryman says he is aware of Cohn's process, but claims it is "as ineffective and unfeasible as the others that have been developed."

Merryman could not, however, say specifically what is wrong with Cohn's process. "If I were to call up the individual companies and ask what is wrong with it, they wouldn't tell me," says Merryman. "That type of thing would be considered proprietary information."

Some 15 to 20 other patents have been filed with the U.S. Patent Office that would make cigarettes self-extinguishing. Some are as simple as one which would require the tobacco in a cigarette to be more tightly packed. But adding more tobacco to a cigarette or packing it more tightly would be costly to the tobacco companies.

Meanwhile, Peter Georgiades, general counsel of Action on Smoking and Health, a Washington-based public interest group, believes he knows the reason the Tobacco Institute opposes legislation requiring self-extinguishing ciagrettes:

"The tobacco industry always opposes any legislation which would control or regulate them, even if only to a small degree. They'e a lot like the anit-gun control people. Even the littlest regulation they preceive as a move by the government to totally dominate them."

Even if legislation is passed this year, a D.C. fire official notes, it won't become effective until 1981. "Between now and then an estimated 1,500 people are going to be killed in cigarette fires. If this type of legislation was passed 10 years ago, we might have 10,000 or 15,000 people alive who aren't. The fire in Fairfax County wouldn't have occured either."

A Tobacco Institute spokesman also commented on the Fairfax fire: "All of this is regrettable. We don't want to encourage the unnecessary death of anybody . . . Perhaps they should have used smoke detectors."