Record Setting Air Quality in 2018

• 2018 had the fewest number of exceedances of the 84 ppb and 75 ppb standards since 1990, with only 24 exceedances of the 84 ppb standard (77% reduction since 1990) and 74 exceedances of the 75 ppb standard (52% reduction since 1990)
• 2018 was a record-setting year for ozone progress with the fewest number of days exceeding both the 84 ppb and 75 ppb 8-hour ozone standards since 1990
• In 2018, the Valley continued to demonstrate ongoing ozone progress by achieving a new record low design value of 90 ppb, which is now only 6 ppb away from attaining the 84 ppb standard.
• In 2018, the Valley continued to demonstrate ongoing ozone progress by achieving a new record low design value of 90 ppb, which is now only 6 ppb away from attaining the 84 ppb standard, despite record wildfire smoke impacts during the summer peak ozone period in 2018.
• Despite significant wildfire smoke impacts across the Valley, 2018 continued the declining trend in the Valley’s 8-hour ozone design value; now only 6 ppb away from attaining the 84 ppb federal 8-hour ozone standard.

Record Setting Air Quality in 2017

Air Quality Index (AQI)

• 2017 recorded the greatest number of Good AQI days across all counties in Valley history

Ozone

• 2017 was a record setting ozone season, with the lowest number of days exceeding the 84 ppb 8-hour ozone standard
• 2017 set a new record low ozone design value for the Valley, bringing the region closer to attaining the 84 ppb federal 8-hour ozone standard

PM2.5

• Even with air quality impacts from wildfires, the year 2017 continued the decline in PM2.5 design values, where the Valley continued to attain the 65 µg/m3 federal 24-hour PM2.5 standard, and continued to make progress toward meeting the other federal PM2.5 standards