MarketWatch: “The EPA says to think of the AQI as a yardstick that runs from 0 to 500. The higher the AQI value, the greater the level of air pollution and the greater the health concern. For example, an AQI value of 50 or below represents good air quality for essentially all the population. A reading above 100 typically means that the outdoor air remains safe for most, but seniors, pregnant people and children are at increased risk. Those with heart and lung disease may also be at greater risk. And an AQI value over 300 represents hazardous air quality that will impact to some degree nearly everyone exposed to the air, even healthy people. Because remembering the severity of number ranges may be challenging, EPA has assigned a color to each range, with green and yellow representing the most favorable conditions, and orange, red, purple and maroon reflective of levels that are progressively worse, topping out at maroon or readings between 301 to 500.For comparison, the record-setting wildfire years of 2020 and 2021 meant that outdoor air near Portland, Ore., on select days produced an AQI above 400…”

• Visit the government-run Air Now site for the latest readings.
• You can also examine longer-term air quality by select region.

• Get air quality data where you live [zip code, city, state]