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Air Quality Alert

...OZONE ACTION DAY ALERT FROM 400 PM WEDNESDAY UNTIL 400 PM THURSDAY... The Colorado Department of Public Health and Environment has issued the following... WHAT...Ozone Action Day Alert. WHERE...Douglas, Jefferson, Denver, western Arapahoe, western Adams, Broomfield, Boulder, Larimer, and Weld Counties WHEN...400 PM Wednesday July 28 to 400 PM Thursday July 29 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Requests to limit driving of non-ZEV vehicles (i.e., gas or diesel) are now in effect until at least 4 p.m. Thursday, July 29, 2021. Ozone concentrations are expected to reach the Unhealthy for Sensitive Groups to Unhealthy range on Wednesday and Thursday. Ozone concentrations in the Unhealthy category are most likely from western portions of the Denver area northward through western portions of Boulder, Longmont, and Fort Collins; and in southern portions of Weld County including Platteville and Greeley. Concentrations of ozone in the Unhealthy for Sensitive Groups category are expected in all other areas of the Front Range region. CDPHE requests that activities, such as driving non-ZEV vehicles (i.e., gas or diesel), be reduced to lessen the impacts on neighboring air quality. Additional air pollution in this region may directly worsen air quality or contribute to precursors which may also adversely affect air quality. For Colorado air quality conditions, forecasts and advisories, visit: HEALTH INFORMATION...Greater likelihood of respiratory symptoms and breathing difficulty in active children and adults and people with lung disease, such as asthma; possible respiratory effects in general population. Active children and adults, and people with lung disease, such as asthma, should avoid prolonged or heavy outdoor exertion; everyone else, especially children, should reduce prolonged or heavy outdoor exertion.

In effect until: Jul-29-2021 4:00 PM

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