"You inhale it with every breath, you take it into your lungs and then it ends up in your bloodstream, and it can have a whole host of adverse impacts," said Heather Heinks, outreach and communications director at the San Joaquin Air Pollution Control District.
Bad air quality is no stranger to Pat Yen, who grew up in the Central Valley.
On Saturday, his family spent time by the water at Woodward Park.
"I parked my car outside and there's ashes," he said.
He said the memories they make are worth being outdoors for a little while.
"That's why I brought my kids over here, to feed the ducks, and just enjoy," he said.
From the Dixie and Caldor Fires in northern California to the French and Walker Fires in Tulare County and Kern County, the Central Valley is seeing smoke impacts in many communities.
"It's terrible. Everywhere you go, there's smoke outside. It's sometimes suffocating," said Fresno resident Amandeep Singh.
Added Jasmeen Mann, another Fresno resident: "Our world has gotten a lot more gray."
The air quality was so bad in parts of the Valley on Friday that the high school football game between San Joaquin and Hanford was canceled at halftime.
Health experts say those with asthma, young children and older people, are especially vulnerable to the pollutants.
For those going outside, properly used masks can help.
"We stress that you check with your healthcare provider. Sometimes N95 masks are useful, but not effective if you've got facial hair or already have respiratory conditions," said Heinks.
The Central Valley saw an unprecedented level of poor air quality last year, and Valley Air says it's shaping up to be just as bad this year. With it being still early in the wildfire season and the lack of rain, experts say it's more important than ever to understand how you can protect yourself.
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