Smoke from fires in California has led to Clark County issuing an air quality advisory through Monday.
Clark County first issued an air quality advisory on July 31.
According to the U.S. Environmental Protection Agency, people who may be most sensitive to elevated levels of particles and ozone include individuals with respiratory problems, cardiac disease, young children or senior citizens.
Exposure to ozone can induce coughing, wheezing and shortness of breath even in healthy people. A seasonal ozone advisory is currently in effect.
The Department of Air Quality monitors air pollution through a network of monitoring sites throughout the Las Vegas Valley. Data is collected from these sites and reported at its monitoring website.