Panel Orders Oxygen Added to Gasoline in Winter : Environment: ARB requires new mix next November to reduce levels of carbon monoxide in air. It is as big a pollution problem as smog is in summer.

To reduce carbon monoxide in California’s skies, the state Air Resources Board will require adding oxygen to gasoline sold during the winter months, starting next November.

The oxygenated fuel is expected to cost about 3 cents more per gallon at the pump. The program is projected to reduce carbon monoxide by about 10% statewide.

Carbon monoxide is an invisible gas that inhibits the blood’s ability to carry oxygen. “It is as much a pollution problem in winter as (smog) is in the summer,” ARB spokesman Bill Sessa said after the board’s unanimous vote Thursday in Sacramento.

“But (smog) tends to be uniform over a broad area, while carbon monoxide tends to accumulate in ‘hot spots.’ You can have a carbon monoxide problem at an individual intersection or in a shopping center parking lot.”

The addition of oxygen to gasoline makes the fuel burn more completely, consuming more of the carbon monoxide that would otherwise flow out the tailpipe.

Oxygenated gas is already sold during the winter in seven U.S. cities: Denver, Phoenix, Tucson, Las Vegas, Reno, Albuquerque and El Paso. “Denver’s had it for several years and the carbon monoxide levels have really come down,” said Don Zinger, acting director of the vehicle pollution office of the U.S. Environmental Protection Agency.

The addition of oxygen is required under the federal Clean Air Act for many areas in California--including the Los Angeles, San Diego and San Francisco regions. The ARB applied the program statewide, in part because so many vehicles travel from areas without carbon monoxide problems to areas with higher levels of such pollution.

Also, ARB staffers said, segregating gasoline markets in the state would make distribution and enforcement too confusing.

The oxygen standards were incorporated into the new “clean” gasoline formula adopted by the ARB last month. That formula, which also reduces the formation of smog-forming compounds year-round, will take effect in 1996.

In the Los Angeles region--consisting of Los Angeles, Orange, Riverside and San Bernardino counties--the federal carbon monoxide standard of 9 parts per million is generally violated from September to March each year.

The ARB, however, chose to start the state’s oxygenated-gas season in November. One reason was that some shortages of the necessary additives are anticipated in the first few years.

Also, the addition of oxygen can exacerbate production of nitrogen oxides. Nitrogen oxides help to form ozone--which, trapped in the lower atmosphere, is the main component of urban smog. Ozone is a powerful lung irritant.

Ground-level ozone violations are also generally common in the Los Angeles area in September and October.

Concern about nitrogen oxides also led the ARB to set the level of oxygen lower than the minimum required by the federal Clean Air Act--2.7% by weight. Under the measure adopted Thursday, California gas will have to include at least 1.8% oxygen by weight, with a maximum of 2.2%.

Zinger, of the EPA, said the state can ask for permission to impose the lower levels if nitrogen oxides would be increased. “But the process would take several months and I don’t think it would be uncontroversial,” he said.

The “winter gas” season will end Feb. 29 in the Los Angeles, San Diego, Ventura-Santa Barbara and Imperial County regions of California, and Jan. 31 elsewhere.