Why do we issue Advisories and Alerts?

The Clark County Department of Air Quality and Environmental Management (DAQEM) issues an Air Quality Advisory if it anticipates that Carbon Monoxide, Particulate Matter (Dust), or Ozone may reach the Unhealthy for Sensitive Groups range (AQI of 101) or higher within the next 12 to 24 hours. Advisories are posted on the website for any of these pollutants, which may be caused by weather related events (such as high winds) or natural events (such as explosions or wildfires). News releases regarding most advisories are also sent to the media, health groups, schools, and to public entities. In general, an advisory is intended to give notice to sensitive groups, such as children, the elderly and people with respiratory illness to watch the weather and monitor air quality in the event that the pollution does reach the Unhealthy range.

If an Air Quality Advisory is issued because of anticipated high winds, DAQEM will advise construction sites to maintain proper dust control or cease operations. Air Quality Advisories are also sent to the National Weather Service and may be noted in NWS forecasts for the Las Vegas Valley. Local residents also can receive air quality advisories via pagers or e-mail via Clark County's free Direct Connect service.

DAQEM issues an Air Quality Alert if and when one or more of the departments 16 monitoring stations detects elevated levels (AQI of 101 or higher) of a pollutant. The Alert is posted on the DAQEM Air Quality Forecast Page and in conjunction with National Weather Service (NWS) announcements.

Air pollution can threaten the health of people, trees, lakes, crops, and animals, as well as damage buildings and the upper atmosphere ozone layer. Air pollution comes from many different sources such as factories, power plants, dry cleaners, cars, buses, trucks and even wind-blown dust and wildfires. Air pollution also can cause haze, reducing visibility in national parks and wilderness areas. Under the Clean Air Act, the Environmental Protection Agency (EPA) sets limits on how much of a pollutant is allowed in the air anywhere in the United States. To help monitor and report air quality, the EPA has set up a "measuring stick" called the "Air Quality Index (AQI). More information about the AQI is available from the AIRNOW website.