The San Joaquin Valley Air Pollution Control District has issued a Valley-wide health alert because of rising particulate matter from fires burning in California.

The smoke billowing into the air from the Soberanes Fire in Monterey County and the Canyon Fire in Santa Barbara is affecting the air quality throughout the San Joaquin Valley, according to Air District officials.

Smoke from wildfires produces particulate matter and contributes to the creation of ozone, which can cause serious health problems including lung disease, asthma attacks and increased risk of heart attacks and stroke. People with existing respiratory conditions, young children and elderly people are especially susceptible to health effects from these pollutants. Air District officials urge residents to follow their doctors’ orders when exposed to wildfire emissions and stay indoors if at all possible.

The poor air quality is expected to continue through Wednesday and then lessen Thursday when a low pressure system moves in and reduces the amount of smoke hovering over the Valley.

The District’s Real-time Air Advisory Network monitors are designed to detect the fine particulates, which are microscopic in size and not visible to the human eye that exist in wildfire smoke. Ash particles are much larger in size and will not be detected by the monitors. Therefore an area may be experiencing impacts from these wildfires while the PM monitor reflects a moderate reading.

“If you can see or smell smoke or ash, that is an indication that you should be treating air quality conditions as “Unhealthy” and remain indoors,” the Air District stated.