Yosemite smoke makes Carson City’s air ‘unhealthy’

Carson City’s air quality entered the unhealthy for sensitive groups category Thursday afternoon.

Carson City’s air quality has diminished to 127 from the Washburn fire burning near the southern portion of Yosemite National Park.

The air quality had been moderate for the past two days, but fell into the Unhealthy for Sensitive Groups category about noon today.

The forecast predicts better air quality Friday and Saturday.

The Washburn fire has burned 4,375 acres as in 23 percent contained as of Friday morning.

The fire will continue to grow over the next few days, according to a fire update Wednesday night.

"The combination of continued warm and dry weather conditions along with the heavy accumulation of large fuels is creating the perfect recipe for the very active fire behavior we are seeing," the update said.

Meanwhile, firefighting preparations had already been underway in the national forest.

"We've brought in Sierra National Forest folks from the get-go, kind of anticipating that this may happen," said Nancy Philippe, a fire information spokesperson.

Containment lines within the park, including along the edge of the grove, were holding, firefighting operations official Matt Ahearn said in a video briefing earlier in the day.

The fire had been entirely within the national park since breaking out July 7, when visitors to the Mariposa Grove of ancient sequoias reported smoke.

Park Superintendent Cicely Muldoon told a community meeting this week that it was considered a "human-start fire" because there was no lightning that day.

Philippe said a park ranger who is a trained investigator was on the scene almost immediately when the fire was reported, and a law enforcement team continues to investigate.

Philippe said she believed they had found the point of ignition, but declined to release further information, citing the active investigation.

The fire in the southern portion of Yosemite forced evacuation of hundreds of visitors and residents from the small community of Wawona, but the rest of the park has remained open to summer crowds.

To help reduce the impact of wildfire smoke, the EPA recommends:

Keep windows and doors closed.

Use fans and air conditioning to stay cool. If you cannot stay cool, seek shelter elsewhere.

Reduce the smoke that enters your home.

If you have an HVAC system with a fresh air intake, set the system to recirculate mode, or close the outdoor intake damper.

If you have an evaporative cooler, avoid using it unless there is a heat emergency because it can result in more smoke being brought inside. If you must use the evaporative cooler, take advantage of times when outdoor air quality improves, even temporarily, to open windows and air out the house.

If you have a window air conditioner, close the outdoor air damper. If you cannot close the damper, do not use the window air conditioner. Make sure that the seal between the air conditioner and the window is as tight as possible.

If you have a portable air conditioner with a single hose, typically vented out of a window, do not use it in smoky conditions because it can result in more smoke being brought inside. If you have a portable air conditioner with two hoses, make sure that the seal between the window vent kit and the window is as tight as possible.

Avoid activities that create more fine particles indoors, including:

Smoking cigarettes.

Using gas, propane or wood-burning stoves and furnaces.

Spraying aerosol products.

Frying or broiling food.

Burning candles or incense.

Vacuuming, unless you use a vacuum with a HEPA filter.

Avoid strenuous activity during smoky times to reduce how much smoke you inhale.

For real time data. go to https://www.iqair.com/ or go to https://fire.airnow.gov/

The Associated Press contributed to this report.