Contaminated air, playing havoc with peoples' health, is also a culprit in power outages throughout Salt Lake Valley.

Outages have inconvenienced many Murray residents - some more than once - four of the past five days. They could find themselves powerless on and off for days to come."It's a combination of circumstances. We haven't had the normal frequency of snow and rain through the fall and into the winter weather," said Gary O. Merrill, assistant general manager, Murray Power Department. "That kind of precipitation would rinse off the ceramic insulators which are crucial to maintaining electrical service without outage."

Intense cold and a temperature inversion have caused heavy fog to shroud the Salt Lake Valley for several days.

"That contributes to a flashing-over or arcing of electricity across the insulators. This results in outages," Merrill said. "It's particularly a problem on the higher voltage lines, which affect the most people."

To avoid recurrent outages, the Murray Power Department is maintaining an intensive inspection program to identify problem areas and replace damaged insulators.

"As a utility, we are doing everything possible to limit or prevent these occurrences and appreciate the patience of our customers as we deal with this circumstance," Merrill said. "We do take this very seriously and will have people back in power as soon as possible."

There were a series of weather-related outages beginning about 5 a.m. Tuesday in the southeast and southwest sections of Murray, city power officials said.At 10:28 a.m. the Utah Power & Light Co. transmission system, which feeds Murray City, failed. All of Murray City was without power for 15 minutes, but the power was restored at 10:43 a.m., John Mohlman, Murray City power general manager, reported.

David Eskelsen, a UP&L spokesman, said details were not available Wednesday.

"It usually takes a few more days before condensation out of the fog starts to create real problems," he said. "It has a lot to do with air pollution, which tends to be high in certain kinds of salts and dust compounds. When the fog condenses in the insulators and other electrical equipment and when enough of the (material) has accumulated, then the dust and moisture will begin to conduct electricity. In the worst cases it can conduct enough current to cause a circuit breaker to close somewhere or the line to fail," Eskelsen said.

Essentially, what needs to happen is that the insulator needs to be replaced or cleaned off by hand - especially if there's an extended period of really foggy weather. But the problems usually occur when heavy fog has blanketed the air for more more than a week, Eskelsen said.

Merrill said what is needed is a good snowstorm.

Heavy fog shrouded much of Utah early Wednesday, but a snowstorm may at least temporarily correct the problem. The chance of measurable snow will increase to 60 percent Thursday, according to the Salt Lake office of the National Weather Service.

The fog has affected more than just power outages.

Areas of dense fog continued during the night in most western Utah valleys, with visibility dropping to a quarter-mile or less at times in Salt Lake City, at Hill Air Force Base and in Provo, Delta and Cedar City. The visibility range was expected to drop to zero in some areas Wednesday morning.

"Travelers should allow extra distance between vehicles and plan for extra time to reach destinations. Highway speeds should be much lower in the foggy areas, particularly in the vicinity of the Salt Lake International Airport, where fog dispersal operations have produced a fine coating of snow on the roadways," said Alex Smith, a forecaster at the Weather Service.

High temperatures in the 30s were forecast for Wednesday, with lows tonight of 20 to 25 degrees. Highs Thursday will be in the low and mid-20s.


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Beware dangers of carbon monoxide

Dr. Lindell Weaver, director of hyperbaric medicine at LDS Hospital, usually treats about two dozen people per year for carbon monoxide poisonings. This winter, because of the cold weather, he's consulted on 53 cases since the middle of December.

Any flame can produce the colorless, odorless gas, which can be harmful or fatal in a poorly ventilated area. He recommends:

- Check furnaces and car exhaust systems. If you smell the telltale odor of natural gas, propane or exhaust, the furnace or car should be fixed.

- Never operate a car in an enclosed space. The warning symptoms of carbon monoxide poisoning are the abrupt onset of headaches, nausea and vomiting, Weaver said.