The Union Carbide Corp. vowed yesterday to conduct a full investigation of the industrial accident that sent clouds of deadly gas through the streets of Bhopal, India, killing hundreds of residents and injuring thousands.

While Union Carbide chairman Warren Anderson prepared to fly to India with a five-member investigative team, corporate spokesmen sought to calm the fears of residents of Institute, W.Va., the company's only U.S. production facility for the lethal chemical called methyl isocyanate.

"It makes everybody nervous," said Rex Pleasant, whose house overlooks Union Carbide's sprawling complex along the Kanawha River about 10 miles west of Charleston.

"Nobody around here would have a chance if that stuff got out," said Reginald Willis, another resident.

"The wind blows this way and I figure if it ever got out it would hug the river and wipe out the town. Then it would wipe out Charleston."

Union Carbide officials declined to say how much of the toxic chemical is produced or stored at Institute, but a spokesman said the company was confident that the plant posed no threat.

"We've been making this stuff here for 17 years and it's never gotten away yet," said spokesman Dick Henderson.

Officials at Union Carbide's headquarters in Danbury, Conn., have shut down indefinitely the methyl isocyanate production line at Institute.

A spokesman said it would remain closed until the company finds out what happened to the Bhopal plant's backup safety system, designed to prevent the type of catastrophe that struck the central Indian city before dawn Monday.

At Bhopal, as in Institute, the chemical is stored in double-walled underground tanks with a ventilation system designed to neutralize poisonous fumes that might escape.

Union Carbide officials said they had no idea why the system failed in Bhopal but speculated that the venting system may have failed when pressure increased inside the tank.

Jackson Browning, a company spokesman in Danbury, said the 7-year-old Bhopal plant was operating under the same safety standards as the West Virginia plant and that its executives and managers had been trained in the United States.

Methyl isocyanate is an intermediary chemical used to manufacture Sevin and Temik, two of Union Carbide's most popular agricultural chemicals.

While only the West Virginia plant manufactures the chemical, it also is used at a Union Carbide facility in Woodbine, Ga., that produces the two pesticides.

According to company spokesmen, the substance is stored under pressure as a liquid, but at temperatures above 70 degrees Fahrenheit it turns into a gas and acts like "a very potent tear gas," irritating the membranes of the eyes, throat and lungs.

In sufficient quantities, the irritation can cause a person's lungs to fill with fluid, resulting in the drowning of the victim.

In Institute, where the 1,400-employe plant provides a bright spot in a state that suffers one of the nation's highest unemployment rates, few residents had heard of methyl isocyanate until this week.

But the chemical was the talk of the town yesterday, and while some residents expressed concern about safety measures at the plant, others said they were not worried about the possibility of a similar accident.

"I don't know what happened in India," said James Brimhall, a vice president of West Virginia State College, whose campus is adjacent to the Union Carbide plant.

"But I doubt whether the plant officials over there have OSHA [the Occupational Safety and Health Administration] or the EPA [Environmental Protection Agency] looking over their shoulders all the time."

Arlene Mann, a waitress, was less sanguine.

"The students who come in here to eat have been talking about what happened in India," she said. "It's got me to the point where if I look out the window and see a blue cloud I'm gonna take off running."

"Me, too," said Willis, "and I'm going to be holding my breath all the way."