Controversial antipollution measures, including a ban on free parking for U.S. employes, are under serious consideration by state and local officials as part of the Washington area's stepped-up efforts to meet new federally-imposed clean-air requirements.

Other pollution curbs currently under study would require additional prohibitions against on-street parking for commuters, higher gasoline or other taxes, and mandatory annual auto inspections that would force drivers to pay for repairs if their cars emit excessive pollution.

The proposals, regarded as possible means of complying with last year's amendments to the federal Clean Air Act, are intended to help lessen the Washington area's most severe and intractable air pollution problems - those caused by auto exhaust fumes.

Many of the measures have been vehemently rejected in the past because of stiff political and public resistance, including objections in Congress. The proposals would cost motorists more money, make parking spaces scarce and expensive and probably force many commuters to stop driving their cars to work.

"We're going to get down to some basic issues of life styles," said Dennis R. Bates, health and environmental protection director for the Metropolitan Washington Council of Governments, in a recent interview. "It is one of the most difficult tasks that I can think of." COG is coordinating the area's efforts to comply with the new federal antipollution requirements.

So tough are the obstacles to cleaning up Washington's air that many officials here say they already are certain the Washington region cannot reduce pollution rapidly enough to meet the federal government's clean-air standards by 1982, the initial target date set by last year's Clean Air Act amendments. Some Washington-area officials also express skepticism that the federal standards will be met even by 1987, the final federally-prescribed deadline.

Washington's air pollution has prompted more than a decade of regulatory crackdowns, legislation, controversy and court battles. Key environmental officials say that government efforts have failed to bring about any significant reduction in the two forms of auto-exhaust pollution, photochemical smog and carbon monoxide, that plague the Washington area, as they do most major American cities.

Photochemical smog, also known as photochemical oxidants, consists almost entirely of ozone and is most prevalent in summer months when a chemical reaction takes place in sunlight between hydrocarbons and nitrogen oxides, both of which are auto exhaust byproducts. Carbon monoxide is produced directly by automobile combustion and is most pervasive in cold winter weather when car engines take longest to start and warm up.

Since 1970, COG has announced 31 air pollution alerts, several of them lasting a week or longer. Thirty of these were hot-weather alerts caused by photochemical smog. A single two-day carbon monoxide alert occurred in January 1973. The frequency of these alerts, as has been underscored this summer (one of the most pollution free in recent years), has depended largely on the area's sometimes erratic weather patterns.

The extent to which air pollution poses a health hazard is not fully understood by medical researchers, although it is widely believed that some forms of pollution, including those caused by auto exhausts, may be harmful to the elderly, infants and persons suffering from respiratory, heart and other ailments. Whether repeated exposure to polluted air causes permanent damage to normally healthy adults is less clear.

The Washington area's sharpest air-pollution controversy was triggered by a plan announced by the U.S. Environmental Protection Agency in 1973 that would have required a series of harsh measures, including a $2-a-day surcharge on parking in major sections of the Washington area. The plan was intended to deter commuters from driving to work and to reduce auto pollution.

Key members of Congress immediately balked at the parking surcharge. EPA quickly retreated, abandoning the surtax. Other major sections of the EPA plan, including requirements for equipping cars with antipollution devices and inspecting autos regularly to enforce exhaust limits, later were thrown out by the U.S. Court of Appeals.

More recently, the Washington area, like most other metropolitan regions, has been required to draw up new plans by next Jan. 1 for meeting federal clean-air standards by 1987. This federal mandate was included in the 1977 Clean Air Act amendments. It carries a threat of sanctions, including possible cutoff of U.S. highway funds, for regions that fail to meet the congressionally-imposed requirements.

One measure that is considered almost certain to be required here, under current federal regulations, is a system of annual auto inspections that would keep cars off the roads if their exhausts exceed pollution limits. In the past, the Maryland and Virginia legislatures repeatedly have refused to set up such inspection programs.

According to federal and local officials, the 1977 Clean Air Act amendments also will give Washington-area governments broader leverage to impose higher parking fees on federal government employes, thousands of whom now are provided with parking spaces free of charge or at low rates. Moves to get federal employes to pay more for parking have met vehement resistance in the past from federal officials. Environmental planners contend that federal workers should pay prevailing commercial parking rates, currently said to be about $60 a month in downtown areas.

In addition to these and other measures currently under study, COG and other Washington-area officials say they also anticipate significant decreases in auto pollution by the late 1980s as a result of federal regulations requiring auto manufacturers to produce clearner-burning engines. These expectations prevail despite last year's congressional decision, under pressure from the auto industry and the auto workers' union, to relax previous auto-pollution deadlines.

Under last year's Clean Air Act amendments, such inspection programs will be required by 1981 or 1982 for any severely polluted region that fails to comply with federal clean-air standards by 1982, a deadline most officials believe the Washington area cannot meet.

While Washington's auto exhaust pollution remains severe, sometimes climbing to three times the level prescribed by federal health-protection standards, Washington-area officials note that substantial advances have occurred in reducing other forms of pollution caused by industrial plants and other nonautomotive sources. There have been sharp decreases, they say, in particulate pollution - that caused by minisucle particles of dust, soot and other objects - and in sulfur dioxide.

Sulfur dioxide pollution has been reduced by about 50 percent here since 1972, said John V. Brink, the District of Columbia's air and water quality chief, in an interview. The decrease occurred largely because of regional restrictions requiring low-sulfur fuel. In the early 1970s, Brink said, the area violated federal clean-air standards for sulfur dioxide, but now is safely within these limits.

The downtown sector of Washington still violates federal antipollution ceilings for particulate matter, but Brink noted in the interview that major decreases in particulates have taken place since 1968, with reductions approaching 50 percent measured at some downtown locations. Officials attribute these decreases partly to regulations curbing pollution from incinerators, industrial boilers and the open burning of debris.

In addition, the Potomac Electric Power Co. has agreed, after protracted court disputes and negotiations, to carry out substantial, costly modifications at its plants to curb particulate pollution, including a $50 million retooling of its coal-burning generating plant beside the Potomac River in Alexandria, expected to be completed by the end of this year.

Brink contends that the major violator of particulate pollution limits in the Washington area today is the U.S. government itself. The General Services Administration operates two heating plants here that long have been the center of a pollution battle in U.S. District Court. While city and federal officials remain in disagreement over many points in this dispute, GSA officials now say they expect to bring their heating plants into compliance with antipollution requirements by early 1981.

Even in their long-stymied efforts to reduce photochemical smog, Washington-area officials point to at least one breakthrough - a controversial program to reduce hydrocarbon fumes at gasoline storage depots and gas service stations through installation of antipollution devices.

Although Washington-area officials say this program has achieved substantial gains, it also has stirred anger and resentment among retail gas industry officials, who complain that some of the costly new antipollution equipment repeatedly malfunction.