WELD COUNTY

Weld County has recently been added to the Front Range area of high ozone levels and must attain the National Ambient Air Quality Standard for ozone level. If the ozone concentrations in the air of the north front range and the Denver Metropolitan areas do not remain below 80 parts per billion in the next three and half years (by 2008) , our area may be re-designated "Nonattainment" for ozone by the Environmental Protection Agency. Extensive, expensive and far reaching consequences will be introduced into our everyday lives to again achieve attainment of this National Ambient Air Quality Standard.

Over the past several years, the atmosphere ozone concentrations have gradually and steadily increased to levels that are of jeopardy to our elderly and young populations, and are known to adversely affect forests and agriculture production. Therefore, Weld County encourages its citizens to reduce ozone air pollution.

Between June 1 and August 31, the Regional Air Quality Commission (RAQC) will work with meteorologists from the Colorado Department of Public Health and Environment (CDPHE) to issue daily advisories that will indicate whether 8-hour ozone levels are high (above 75 ppb). The RAQC will issue advisories to the media, local governments, businesses, and citizens by 4:00 p.m. each day. The advisories will encourage citizens to reduce ozone- causing activities until ozone levels fall.

What is Ozone?

Ozone is formed when emissions from everyday items - such as local industry, gasoline-powered vehicles and lawn equipment, and household paints, stains, and solvents - combine with other pollutants and "cook" in the heat and sunlight to form ozone. Ozone is most likely to form during the summer months on long, hot, still days.

Health Impacts

In the stratosphere, miles above the earth, ozone provides a beneficial "umbrella" to protect life from harmful solar rays. However, at ground level, ozone is harmful to breathe in high concentrations.

The elderly, young children, and those with pre-existing respiratory infections are particularly at risk from exposure to ground-level ozone, but even healthy adults who spend a lot of time working or exercising outdoors may be affected by high ozone levels. Symptoms of ozone exposure include stinging eyes and throat, chest pains, coughing, and breathing difficulty. To learn more about the health effects of zone, click here: Health Effects.

Causes

Operating and refueling vehicles account for 45 percent of ozone pollution in the seven-county Denver Metropolitan area, Ft. Collins, Greeley, and Colorado Springs. Other sources of VOCs (volatile organic compounds) and NOx (nitrous oxides) are gas-powered lawn equipment, industrial operations, household solvents, paints, and de-greasing agents.

Simple Solutions

Simple, voluntary measures - like those listed here suggest ways individuals can minimize ozone pollution. They are particularly important on days that the Regional Air Quality Council (RAQC) announces high ozone advisories.

What is an ozone advisory?

An ozone advisory is simply a forecast of expected ozone levels in the seven-county Denver Metro area including Ft. Collins, Greeley, and Colorado Springs. The Regional Air Quality Commission issues two types of ozone advisories:

A SUMMER OZONE POLLUTION FORECAST means that CDPHE meteorologists expect low ozone levels across the region. This type of advisory remains in effect until further notice.

A SUMMER OZONE POLLUTION ACTION ALERT means that CDPHE meteorologists expect weather conditions to lead to increased ground-level ozone concentrations over the next twenty-four hours. An alert will remain in effect for twenty-four hours and will either be called off or re-issued at that time.

Advisories: What do they mean?

Red Advisories indicate that conditions are poor or are expected to worsen. They activate mandatory residential burning restrictions and call for voluntary driving reductions. Residential burning restrictions apply to everyone in the seven-county Denver area residing below 7,000 feet in elevation, with exceptions for those using EPA-certified or other approved devices according to Colorado Regulation No. 4. Public participation during a "Red Advisory" will help lower winter air pollution levels in the Denver area on days when conditions could lead to violations of one or more air pollution standards.

Blue Advisories indicate that conditions are good or are expected to improve. They require no public action. However, the use of alternate transportation is encouraged whenever possible, and motorists are encouraged to properly maintain their vehicles

No fuel of any kind can be burned in a unapproved stove or fireplace when a "Red Advisory" is in effect. However, certified wood burning stoves and pellet stoves (Colorado Phase III or U.S. EPA Phase II) and natural gas fireplaces and fireplace inserts are exempt and can be used any time. (Click here for information on Colorado Regulation No. 4 and for a list of approved stoves and fireplace inserts.

Who issues ozone advisories?

The Regional Air Quality Council (RAQC) - the lead air quality agency for the seven-county Denver metro area including Ft. Collins, Greeley, and Colorado Springs works closely with meteorologists from the Colorado Department of Public Health & Environment (CDPHE) to issue summer ozone advisories. CDPHE meteorologists determine the alert and RAQC issues them to media, individuals, local governments, and businesses.

How does the RAQC determine when to issue an Ozone Action Alert?

Meteorologists at the CDPHE analyze weather forecasts and ozone monitoring data from around the seven-county region to predict expected ozone levels. In general, hot, sunny and windless conditions increase the likelihood of high ozone concentrations, while clouds, wind and more moderate temperatures can help prevent ozone formation.

When do the CDPHE and the RAQC issue ozone advisories?

CDPHE meteorologists predict expected ozone levels each afternoon. The RAQC issues ozone advisories at 4:00 p.m. whenever there is an alert OR to call off an alert with a low ozone "forecast". Ozone ALERTS are re-issued daily until they are called off. Ozone FORECASTS remain in effect until an ALERT is called.

To whom does the RAQC issue ozone advisories?

The RAQC issues advisories to the media (usually to the city, weather and/or news desk), interested individuals, businesses, and local governments.

What should I do with an ozone advisory?

Members of the media are asked to print or broadcast daily ozone advisories so citizens can avoid exposure and modify ozone-producing activities (Voluntary Actions ). Local governments should notify employees and the public about advisories via e-mail and websites. Businesses, local governments and individuals can modify activities to reduce ozone pollution.

Current Air Quality Conditions

For current air quality conditions refer to the main web page for Weld County's Department of Public Health & Environment of the Environmental Health Services main page or contact one of the resources listed below.

• 1-888-4THE-AIR (1-888-484-3247)
• Check the Denver Rocky Mountain News, listen to the radio, or watch your favorite local newscast. Most media include information about the current advisory in their news, weather, or traffic updates.
• Visit the Air Pollution Control Divisions (CDPHE) web site at http://apcd.state.co.us/advisory.aspx

Should atmospheric conditions suggest increased ground-level ozone concentrations, we will issue an ozone advisory for the Denver Metropolitan area, the Ft. Collins-Greeley area, and Colorado Springs. Check this website (http://apcd.state.co.us/psi/) often for a report on current air quality conditions and to learn if an ozone action day alert is in effect.

For an AQI value that considers all pollutants, please click here .

Measuring Pollution:

Two scales are used to report on air pollution levels. The Air Quality Index (AQI) and the Visibility Standard Index (VSI) reflect actual air quality conditions. Calculations are used to convert actual pollutant concentrations to the following user-friendly scales: