An air quality alert first issued last week was extended until Thursday morning due to continuing wildfire smoke. The San Joaquin Air Pollution Control District says there are intense amounts of smoke from the KNP Complex and Windy Fires in Sequoia National Park and nearby forest.
A few days ago, the smoke hung in the atmosphere, but recently, it has settled in the valley like a dense fog. The air district measures air quality levels on a scale of 1 to 5, which indicate levels for ROAR or Real Time Outdoor Activity Risks. Heather Heinks, the outreach and communications manager at the San Joaquin Air Pollution Control District says the level has gone as high as 5 in many areas in recent days, but can change depending on where the plumes of smoke move.
“You can see the windows of opportunity to still have outdoor activities,” she says. She encourages people to monitor air quality conditions by the hour. She recommends people download the Valley Air district’s app or the EPA’s AirNow app on their phones, or go to the air district’s wildfire resource page.
Heinks says weather patterns can cause air quality conditions to shift. Rain, moisture and most of all, wind can help to clear out the smoke that’s trapped in the valley.
“As we move through the next few days we anticipate the Central Valley region to have a heavy influence of particulate matter pollution,” she says.
At level 5, it’s recommended that everyone stays indoors. If you have to be outdoors, it’s recommended you wear a fitted N95 mask to best filter out the pollution. Heinks says being outdoors is dangerous.
“And so you walk outside to a haze, you can smell it. If you're smelling it, that definitely means you're breathing in fine particle pollution,” she says.
Prolonged exposure to PM 2.5, or microscopic levels of particulate matter can lead to respiratory illnesses. Those most at risk are people with heart or lung disease, older adults and children.