The U.S. Environmental Protection Agency has signed off on County plans for maintaining the agency’s 1997 national ambient air quality standard for ozone. The decision will be official when it is published in the Federal Register in the next few weeks. The designation of attainment for the 1997 standard will remain in effect through 2022.
Officials determined that improvement in air quality is the result of local, state and federal measures. They include cleaner fuel, federal requirements for low-emission vehicles, local improvements in public transportation and road construction and greater understanding about the public’s role in fighting ground-level ozone.
Unhealthy doses of ground-level ozone can reduce lung function and worsen respiratory illnesses such as asthma or bronchitis. Exposure to ozone also can induce coughing, wheezing and shortness of breath even in healthy people. When ozone levels are elevated, officials advise everyone to limit strenuous outdoor activity.
“This is really good news, but we can’t let our guard down,” said Commission Chair Susan Brager. “We all have to do our part to ensure that we continue to keep ozone levels depressed, especially during the warm-weather months, when ozone levels are at their highest.”
Ozone season arrives in May each year and County officials issue a season-long advisory, which remains in effect through September. During this time, weather conditions and pollutants can trigger a build-up of ground-level ozone during afternoon hours due to a combination of factors, including strong sunlight, hot temperatures, and pollutants from automobiles and other sources such as wildfires, as well as air blown into the valley from Southern California.
Today’s announcement means the County met the five criteria for designation of attainment: (1) Having met the 1997 8-hour ozone national ambient air quality standards, which is 84 parts per billion (ppb), (2) that relevant portions of the State Implementation Plan are fully approved, (3) that improvement in air quality is due to “permanent and enforceable reductions in emissions,” (4) that all requirements have met the pertinent parts of the Clean Air Act, and (5) that the County has a fully approved Ozone Maintenance Plan.
While County officials say the move is significant, even stricter ground-level ozone standards are being proposed. In 2008, the EPA adopted a new, more stringent standard for ozone of 75 ppb. Air quality officials say the County is very close to exceeding the new standard.
“We meet the new health-based standard for ozone, but just barely,” said Lewis Wallenmeyer, director of the County’s Department of Air Quality. “We need to remain vigilant in our efforts to reduce ozone pollution.”
The following actions help reduce the formation of ground-level ozone:
- Fill up your gas tank after sunset.
- Plan errands so they can be done in one trip.
- Try not to spill gasoline when filling up, and don’t top off your gas tank.
- Keep your car well maintained.
- Use mass transit or carpool.
- Don’t idle your car engine unnecessarily.
- Walk or ride your bike whenever practical and safe.
- Turn off lights and electronics when not in use. Less fuel burned at power plants means cleaner air.
- Consider low-maintenance landscaping that uses less water and doesn’t require the use of gas- powered lawn tools to maintain.
Air quality officials encourage residents to sign up for free text and e-mail advisories and air quality forecasts through the department’s EnviroFlash service at www.enviroflash.org. The service has more than 2,100 subscribers. Daily air quality reports and forecasts also are posted on the Department of Air Quality website. Five-day forecasts cover ozone as well as carbon monoxide and dust. Air quality officials also send advisories to local media, schools, government jurisdictions and the National Weather Service if weather conditions and other factors seem likely to trigger the formation of a pollutant of concern in the valley. Alerts are posted on the forecast page if any of the department’s 11 monitoring stations detect unhealthy levels of the pollutant at a single site in the valley over a specific period of time set by the EPA.
Local air quality has improved significantly since July 2001 when the County Commission was designated as the air pollution control agency for Southern Nevada. In 1985 the valley logged a record 41 unhealthy air days due to carbon monoxide. In January 1993 the area was designated as serious non-attainment for particulate matter (PM-10), a form of dust pollution. The County now meets health standards for carbon monoxide and PM-10.
Today’s announcement coincides with the issuance of an advisory that will be in effect from this evening through tomorrow for potentially elevated levels of smoke over the New Year’s holiday due to local fireworks. Cold weather combined with light winds and a potential temperature inversion may cause smoke to remain at a low elevation, increasing the concentration of air pollution. Air Quality officials say smoke is made of small dust and soot particles and other pollutants that can aggravate respiratory diseases.
At this time, unhealthy levels of air pollution are not occurring. Air Quality officials will continue to monitor conditions and will post an alert on the forecast page of the DAQ website if unhealthy levels occur. Airborne smoke is a form of inhalable air pollution called particulate matter, or PM, which aggravates respiratory diseases such as bronchitis and asthma. It may be best for children, the elderly and people with respiratory diseases to stay indoors under smoky conditions. Other suggestions include:
- Limit outdoor exertion.
- Keep windows closed.
- Use your prescription allergy medication or over-the-counter hay fever or sinus medications if you experience symptoms of itchy eyes, a runny nose or congestion. ###
Clark County is a dynamic and innovative organization dedicated to providing top-quality service with integrity, respect and accountability. With jurisdiction over the world-famous Las Vegas Strip and covering an area the size of New Jersey, Clark is the nation’s 14th-largest county and provides extensive regional services to more than 2 million citizens and 42 million visitors a year. Included are the nation’s 8th-busiest airport, air quality compliance, social services and the state’s largest public hospital, University Medical Center. The County also provides municipal services that are traditionally provided by cities to almost 900,000 residents in the unincorporated area. Those include fire protection, roads and other public works, parks and recreation, and planning and development.