SACRAMENTO, Calif. — With this year's fire season already being severe in Northern California, smoke and haze has become more and more prevalent across the state as fires burn this week.
Most of the ongoing fires has seen the smoke streaming north and east to other states, but with a wind shift Wednesday morning, many more locations in California are experiencing very thick smoke and haze.
As of Wednesday morning, many locations near Sacramento, Woodland, Davis and Dixon have reported Air Quality Index (AQI) numbers over 200.
This would be considered "unhealthy" air and in some areas that have over 250 AQI are considered "hazardous." Some of the worst air quality related to smoke is in the Tahoe Basin with Incline Village and Homewood reporting AQI scores over 400 to 500.
The poor air quality forced Sacramento County Public Health to shut down the COVID-19 vaccine and testing site at Cal Expo.
In a statement about the closure, county health officials said, “Due to the air quality in the Sacramento region, the Curative CalExpo team has made the decision to close for the day to prioritize the health and safety of staff and patients.”
People whose appointments were canceled Wednesday are being notified to return on Thursday. Those who intended to get a walk-up vaccine or test is encouraged to go to the Public Health COVID website to find alternate vaccine or testing sites.
Thursday’s hours will be assessed based on air quality conditions, officials said.
Air quality is measured on a scale called the Air Quality Index. The scale has been popular in many countries to try and get a universal standard for air quality and health.
These reports are coming from a variety of sensors, many from private customers sharing data on the website purpleair.com, which is network of data for air quality measuring a specific size of particle connected to smoke. Another resource used is sparetheair.com.
Using both resources and their AQI numbers, air quality in Northern California is among the worst in the world. In many specific spots, they would rank as the worst in the world.
Well-known poor air quality countries like India and China are reporting AQI numbers in the 150 to 200 range and many Northern California areas are well above the 200 AQI as of Wednesday morning.
Thursday night, the winds are expected to calm down and reverse direction in some spots to bring some relief to the Valley, but with ongoing large fires smoke and haze will be lingering the rest of this week.
Experts suggest to reduce activities outside during very poor air quality days and put as many barriers as possible. Masks, such as N95, will help with smoke particles to an extent. If you are concerned about smoke remember that if you smell it, it is in your area and you may need to take action until it disperses.
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