Why smog standards are important for our health

Nearly 40 percent of Americans live in areas with unhealthy levels of smog pollution.

EPA is failing to protect Americans from deadly smog pollution. We're fighting back.

What is smog?

Across many major cities, a hazy brown soup of pollution hangs over the skyline, especially in the warmer months. This is smog, known more specifically as ground-level ozone.

Smog is formed when industrial emissions from power plants, factories, cars, and other sources react with heat and sunlight in the atmosphere.

Why is it harmful?

When inhaled, smog irritates our airways, increasing our risk of serious heart and lung diseases. These health risks are why many cities monitor smog levels. On a high ozone-alert day, for example, your eyes and throat may burn, and you may cough and wheeze.

Reducing smog will protect all Americans – especially our kids, older adults and people active outdoors.

Is anyone trying to fix it?

Every five years, the U.S. Environmental Protection Agency reviews air quality standards in light of any new medical evidence, and makes updates, if appropriate.

A 2015 review lowered the nation's air quality standard for smog pollution from 75 parts per billion (ppb) to 70 ppb. EPA estimates that when the health-based standard is implemented, each year it will prevent:

  • Up to 660 premature deaths.
  • 230,000 asthma attacks in children.
  • 160,000 absences from school.

EPA must take action to implement the updated smog standard, including letting all Americans know whether their air is safe to breathe and ensuring that, where communities do have harmful smog pollution levels, regulators are working to develop and implement solutions to restore clean, healthy air.

The science on ozone's health effects is rock solid.

Elena Craft, Senior Health Scientist

However, the EPA under the Trump administration is not fully implementing the 2015 smog standards.