BoCo Alert System

Level 2 Fire Restrictions in effect for western Boulder County (more). See flyer and map for details.

Denver's brown cloud


Today’s Ozone Action Alert Status

Unlike the good, protective ozone layer in the upper stratosphere, ground-level ozone is a harmful air pollutant that affects all of us. It’s formed when emissions from everyday activities like:

  • Driving
  • Fueling vehicles
  • Industrial emissions from oil and gas, power plants, and other sources
  • Painting
  • Solvent use
  • Lawn mowing

These activities emit volatile organic compounds and nitrogen oxides that when combined, “cook” in heat and sunlight to form ozone. Hot summer days often provide the perfect conditions for increased ozone pollution.

Ozone continues to be a serious health issue and air pollution concern in Boulder County, and the nine-county Denver Metro/North Front Range region (which includes Adams, Arapahoe, Boulder, Broomfield, Denver, Douglas, Jefferson, Larimer, and Weld Counties). There are nine monitors in the area that often record ozone levels that exceed the ozone standard, including the monitors in Boulder and Rocky Mountain National Park.

Ozone can worsen lung conditions such as asthma and can permanently damage lungs after repeated exposures. Before exercising or spending a lot of time outdoors on hot summer days, people should check the ozone alert status. Children, older people and those with lung conditions suffer more ill effects from ozone pollution, though it can cause chest pains, coughing and throat irritation in anyone, even at low levels.

What Can I Do?

What is Boulder County Doing?

  • Boulder County engages at the state level to see that regulations are passed to reduce emissions from vehicles, oil and gas and other industrial sources.
  • Boulder County Public Health, Jefferson County Public Health, Denver Public Health, and Denver Department of Public Health and Environment released a report and fact sheet, and sent a letter to the Governor urging Colorado to adopt Advanced Clean Car Standards in order to continue to reduce the air pollutants that form ozone and also to combat climate change from greenhouse gases in vehicle exhaust.
  • Boulder County works with local businesses to promote alternative transportation, energy efficiency and pollution prevention through its Partners for a Clean Environment Program.
  • Boulder County Public Health has a Voluntary Oil and Gas Inspection Program. Public Health continues to work with oil and gas operators to perform leak detection and repair visits at their active facilities in Boulder County. The program has been successful in identifying gas leaks with an infra-red camera, following up with operators as they make necessary repairs, and establishing good working relationships with the local operators.
  • In March 2017 the Boulder County Commissioners passed the strongest oil and gas regulations in Colorado.

Learn More

Contact Us

Air Quality Program

Main: 303-441-1564
Submit a question


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