Smoke drift across region harms air quality |

Smoke drift across region harms air quality

Air quality in Nevada County was classified as unhealthy for sensitive groups last week and remained so through the weekend, a move largely driven by wildfire smoke particulate, experts said.

On Thursday, the Air Quality Index (AQI) reached a level of 140 for Nevada and Placer counties — considered unhealthy for sensitive groups, according to the Northern Sierra Air Management District. Friday and Saturday the level reduced to 136 and then 126, still unhealthy for sensitive groups, and those with compromised immune systems.

An email alert issued Monday by the air quality management district in Grass Valley warned of prolonged and widespread smoke from a number of wildfires, but predominantly from the Dixie Fire. Poor air quality possibly attaining hazardous levels is expected to persist as long as the fires are active. Smoke will vary considerably depending on fire behavior and the weather.

“If you see or smell smoke, it is not healthy to breathe it,” said Gretchen Bennitt, executive director of the air quality district. “Especially if you’re anybody with heart/lung disease, asthma, exercising or working strenuously outdoors.”

Bennitt said people should limit outdoor activity, even if healthy, during unhealthy air quality episodes, or remain indoors, drink plenty of water and avoid additional smoke by shunning tobacco or barbecued cooking.

“Best hope for people to protect themselves is sign up with the Health Advisory on the Northern Sierra Air District’s website:,” she said. “But smoke impacts depend upon meteorology, location and the activity of the wildfire.”


The Dixie Fire has merged with a smaller blaze burning along its eastern edge that continued to spread its destructive force Sunday into Plumas County. The Fly Fire, at 4,300 acres and 5% containment, started just east of the Dixie on Thursday. The smaller blaze was subsumed into the Dixie Fire, now at 190,625 acres burning near the border of Butte and Plumas counties.

The Tamarack Fire has burned 66,744 acres about 20 miles southeast of South Lake Tahoe. It’s 27% contained.

Over the past few days smoke from the Dixie Fire spread into Nevada County as well as other Northern California regions and the state of Nevada.

Nevada County Public Health Department recommends if any resident sees or smells smoke over the next several days to minimize outdoor activity even if a person is healthy, stay indoors with windows and doors closed as much as possible while running the air conditioning on the recirculate mode, if available, and contact a personal physician if chest pain, shortness of breath or severe fatigue occurs.

More is known about the short-term health effects of smoke impacts, but research is underway to look at the potential long-term health impacts of breathing smoke, said Melanie Turner, spokesperson of the Cal EPA Air Resources Board.

“Health impacts can be immediate or occur days later. Smoke exposure can also lead to decreased lung function,” she said.

Wildfire smoke is a mix of gases and fine particles from trees, plants and buildings. Inhaling smoke can immediately cause coughing, wheezing, irritated sinuses, rapid heart beat and chest pain.

William Roller is a staff writer with The Union. He can be reached at

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