The Environmental Protection Agency, in its first attempt in nearly a decade to add a pollution-control device to cars, announced plans yesterday to require that all new vehicles be equipped with special cannisters to trap gasoline fumes emitted at the service station pump.

At the same time, the EPA proposed tighter standards on the volatility of gasoline, making it less likely to release vapors from hot engines or station pumps.

The proposed controls, which the EPA estimates would add $19 to the price of a new car and one-half cent to every gallon of gasoline, are designed to reduce hydrocarbon emissions from gasoline that contribute to one of the nation's most dangerous and stubborn air pollutants -- ozone.

EPA Administrator Lee M. Thomas said the controls are necessary because of the anticipated failure of many major cities to meet federal standards for the pollutant by the Dec. 31 deadline. Low-altitude ozone causes respiratory and pulmonary problems, and the EPA has sought to reduce it since the Clean Air Act was passed in 1970.

Both proposals face formidable industry opposition in the public review process, which Thomas said is likely to take at least a year.

Auto makers object to the vapor-control devices on the basis of cost -- which spokesmen said is likely to reach $80 per car in the first years -- and safety. Allied with property and casualty insurers, they express fears that an additional tube directing gasoline vapors to the engine will increase the risk of fires.

On the gasoline volatility issue, the oil industry said the EPA plan would raise refinery costs by billions of dollars and increase the nation's reliance on imported oil while achieving little in improving air quality.

Even environmentalists were dissatisfied by the EPA proposals, contending that they would take too long to implement and should be augmented in the meantime by gasoline vapor controls at the pump, such as those required in the District of Columbia.

The EPA plans call for a phase-in of the new volatility standards by 1992, with the cannisters ready for 1991 model cars after a two-year development period.

The proposed gasoline-vapor controls have been under consideration for more than a decade as the EPA has grappled with the ozone problem. High in the atmosphere, naturally occurring ozone helps shield the Earth's surface from ultraviolet rays. But at low altitude, formed by the mixture of sunlight and volatile organic compounds released from automotive and industrial sources, it is an air pollutant.

Thomas said that when all vehicles on the road have the devices -- a period EPA estimates will take 15 years -- the vapor controls proposed yesterday will cut by 10 percent the emissions of hydrocarbons, the largest unregulated constituent of low-altitude ozone.

EPA is proposing the first new pollution device on cars since the agency required a one-liter, carbon-activated cannister in 1978 to absorb gasoline vapors released from the fuel tank and carburetor. Those fumes rise from under the hood, especially in hot weather when high temperatures turn the liquid fuel into vapor.

The latest device designed by the EPA is aimed at capturing vapors that come back from the vehicle's gas tank after refueling. In a few cities, such as Washington, devices on the pump trap the fumes and direct them to the service station tank. In most places, however, the fumes waft out of the gasoline tank into the atmosphere.

The EPA device, designed by its Motor Vehicle Emissions Laboratory, features a rubber tube that would collect the backup fumes and direct them to a three-liter cannister filled with absorbent charcoal. The fumes would eventually be sucked out of the container by the engine and burned off.

Thomas said he considered other remedies, including gas pump devices, but favored the "onboard controls" because they are easier to enforce.

The auto industry has promoted pump controls on the grounds that they are less costly and can be more selectively mandated for cities where ozone is a problem. But Thomas said he preferred the vehicle-installed devices in all cars because they would capture other dangerous byproducts of gasoline, including benzene, which causes cancer in humans.

Thomas said the cannisters could be produced at "reasonable" price, but the industry disagrees.

The plan is a "bad bargain for the American people," said a joint statement by General Motors, Ford and Chrysler. "We are certain that if the American people could review this complicated matter, they would conclude that they would rather spend these billions in areas of public health where actual progress can be made."

Both auto and insurance industry spokesmen cited safety concerns raised by the National Highway Traffic Safety Administration, which in June noted "some unquantifiable, increased risks of crash and noncrash fire associated with onboard controls." The highway safety agency said such risks could be reduced if the industry had enough time to develop the technology.

"I have a feeling that the EPA is trying to solve one health problem by creating another," said Brian O'Neill, president of the Washington-based Insurance Institute for Highway Safety, which represents the nation's largest property and casualty insurers.

Thomas said that the EPA's engineers believe the vapor-control devices are safe and that the public review process will resolve disagreements over both safety and cost.

The proposal to cut the volatility of gasoline during the hot summer months by 20 percent was denounced by the American Petroleum Institute as "unwise, unwarranted and contrary to the national interest" because, the institute said, it would lead to imports of more foreign oil.Staff writer Warren Brown contributed to this report.