Salt Lake City is among 20 cities listed by the federal Environmental Protection Agency as violating air-quality standards for both ozone and carbon monoxide.

Provo and Boise were on the list of cities violating carbon monoxide standards.This doesn't mean residents have to wear an oxygen mask when venturing outdoors, or that the EPA will be moving its forces in to clean up.

Although Congress required that states be in compliance with the Clean Air Act by last year, a state health official maintains, "the Clean Air Act isn't very clear as to what happens now."

Congress has dropped the ball, neglecting to tell states what regulatory measures must now be adopted.

"But it's something we have to be concerned about because we are a fast-growing area, and these (agents) post a significant threat to public health," said Kenneth Lee Alkema, director, Utah Department of Environmental Health.

Alkema said Salt Lake County's carbon monoxide level has improved greatly over the past two years because of the inspection-maintenance program.

Although Provo instigated a similar inspection program 11/2 years ago, its carbon monoxide levels are much worse; concentration levels haven't been brought down, Alkema said. "Provo still exceeds standards substantially and frequently in the winter, while Salt Lake only does it a few days now."

The carbon monoxide air-quality standard calls for no more than one eight-hour period in the year during which any monitor in an area exceeds 9.0 parts per million. In other words, the first eight-hour period over the limit doesn't count.

Provo was No. 12 on the list of carbon-monoxide violators. Its second-highestreadings were 13.3 in 1987 and 14.4 in 1986. The estimated number of days in each year during which the eight-hour standard was exceeded was 20 in 1987 and 24 in 1986.

Boise, No. 51 on the list of 59 areas, had for its second-highest readings 8.3 in 1987 and 9.7 in 1986. There were no such days in 1987 and three in 1986 in which it was estimated that the eight-hour standard was exceeded.

Salt Lake City was No. 30 on the list of areas in violation of carbon monoxide standards with second-highest readings of 9.8 in 1987 and 11.6 in 1986 and estimated numbers of days exceeding the standard of two in 1987 and nine in 1986.

The ozone level, Alkema said, is a different story.

Salt Lake and Davis counties, he said, exceed the ozone standard several hours each year. By comparison, Los Angeles, exceeds it three or four months at a time.

"However, it's a standard that has no margin of safety," he stressed. "The health of people who have lung diseases, such as asthma and emphysema, could be immediately affected so the standard should never be exceeded."

The ozone air-quality standard calls for no more than one hour in the year during which any monitor in an area exceeds 0.12 parts per million. The EPA tries to smooth out fluctuations caused by abnormal weather by looking at the fourth highest reading over a period of three years.

Salt Lake City was 26th on the list of 68 areas violating ozone standards. Its fourth-highest reading during 1985-1987 was 0.15 and it was estimated the city had 3.8 days in that period in which the ozone concentration exceeded the 0.12 ppm limit for an hour or more.

In 1987, Salt Lake City's second-highest one-hour reading was 0.11 and it was estimated the standard was exceeded one day during the year.

In addition to Salt Lake City, the cities that were on both lists were Los Angeles, Houston, New York, Baltimore, Fresno, Sacramento, El Paso, St. Louis, Modesto, Washington, Boston, Nashville, Phoenix, San Francisco, Cleveland, Detroit, Memphis, Pittsburgh and Raleigh.