ANCHORAGE, Alaska (AP) -- National Weather Service forecaster Aaron Tyburski knew smoke from forest fires had lowered air quality outside his Fairbanks office. What he didn't count on was the haze following him inside.
He kept cleaning his glasses Monday until he realized that smoke had penetrated the steel-and-glass building.
``We even have reduced visibility from one side of the room to the other,'' he said.
A change of wind direction blew smoke from the 55,000-acre Boundary fire 50 miles north of Fairbanks and other blazes into the Fairbanks North Star Borough, creating hazardous air conditions for the 82,000 residents.
The borough's air quality office warned the elderly and children to stay indoors, and all others to avoid strenuous outdoor activity, after smoke elevated carbon monoxide levels and particulates.
Particulates were in the hazardous category, said Glenn Miller, borough transportation administrative manager. The carbon monoxide level reached 9.1 parts per million, a shade under the federal acceptable maximum of 9.5 parts per million.
Particulates are solids measuring 2.5 microns or smaller.
Typically there are 10 micrograms per cubic meter in Fairbanks, Miller said. Environmental Protection Agency standards are exceeded at 65 micrograms in a 24-hour period and rated hazardous at 350 ppm.
A monitor on the state building in downtown Fairbanks reached 995 micrograms per cubic meter and then ``crapped out,'' Miller said.
``We're nearly three times over the hazardous level, and then it stopped working,'' Miller said. ``We probably had levels that exceeded that.''
Particulates can aggravate respiratory problems for people with lung and heart diseases, Miller said, and cause serious health effects in the general population.
``There's nothing that we can do to alleviate that other than take precautionary measures,'' Miller said.
Tyburski, the weather forecaster, said relief probably was not in sight for the rest of the week.
``It looks like the weather pattern that's set up will probably keep the smoke in the area for the rest of the week,'' Tyburski said.
A high over central Alaska is keeping temperatures in the mid-80s. The high also brought in northeasterly winds Sunday night, lowering visibility to about one-quarter mile.
``It's very conducive to help those fires to grow and move along,'' he said. ``If we seen anything, we'll probably see the winds pick up.''
The Boundary Fire jumped the Steese Highway over the weekend, forcing its closure Sunday night. State Division of Forestry spokeswoman Brett Ricker said late Monday afternoon the highway, which runs between Fairbanks and Circle on the Yukon River, had been reopened to traffic with forestry officials leading vehicles by pilot car between miles 50 and 66.
Much of the fire is in limited suppression areas where firefighters monitor but don't fight the blaze. One structure in a limited suppression area, a building used as a garage at a mining camp on Sourdough Creek, has burned, Ricker said.
``Suppression efforts are mainly on the southwest corner of the fire,'' Ricker said. ``That's where the most structures and homes are near.''
In all, 55 fires are active in Alaska, according to the Alaska Interagency Coordination Center.
One is the 120,660-acre Pingo fire, the largest of the blazes in the Solstice complex of fires near Venetie, a village 160 miles northeast of Fairbanks and 150 miles west of the Canada border.
Crews have connected pumps and hoses to the Chandalar River to help reinforce a 50-foot-wide firebreak surrounding the village of about 200 people, said fire spokesman Tom Kempton at Fort Yukon. The blaze over the weekend had halted about 1.5 miles from the village and had moved no closer Monday, he said.
The Taylor Highway north of Tok remains open to traffic with restrictions. Drivers can expect smoky conditions, long delays and firefighters and equipment on the road, according to the fire coordination center.
The 18,000-acre Camp Creek Fire, burning within 1.5 miles of the Pogo Mine 40 miles northeast of Delta Junction, was staffed with 38 firefighters working to prevent damage to structures.