Air Quality Forecasts Renew Statewide

RALEIGH - The "ozone season" begins Thursday as state and local environmental agencies renew their daily air quality forecasts for ozone in metropolitan areas across North Carolina.

This is the third year under new ozone standards that the U.S. Environmental Protection Agency adopted in 2008, and the EPA is considering making the standards even more stringent. Despite the tougher limits, North Carolina had its lowest ozone levels on record in 2009 - a trend that state air quality officials hope will continue.

"Last year we anticipated an increase in Code Orange and Red days due to the lower ozone standard, but we were pleasantly surprised," said Keith Overcash, director of the N.C. Division of Air Quality (DAQ). "Air quality is improving, but we are likely to face stricter standards aimed at further protecting public health and the environment."

The daily air quality forecasts focus on the pollutant likely to reach the highest level on a given day, which could be ozone or particle pollution. The color-coded forecasts show whether air quality is likely to be good (green), moderate (yellow), unhealthy for sensitive groups (orange), or unhealthy (red).

State and local air quality programs issue air quality forecasts for ozone from April through October in the Asheville, Charlotte, Fayetteville, Hickory, Triad, Triangle and Rocky Mount metropolitan areas. Forecasts are issued for particle pollution year-round for all of the metro areas except Rocky Mount, which lacks a particle monitor.

Meteorologists issue the air quality forecasts at 3 p.m. every day for the following day. On Code Orange and Red days, the forecasts also suggest things people can do to protect their health and reduce air pollution, such as limiting outdoor activities, avoiding strenuous exercise and driving less.

Ozone is North Carolina's most widespread air quality problem, particularly during the warmer months. High ozone levels generally occur on hot sunny days with little wind, when pollutants such as nitrogen oxides and hydrocarbons react in the air. High levels of fine particles are more of a problem in the western Piedmont region but can occur throughout the year, particularly during episodes of stagnant air and wildfires.

Ozone, a highly reactive form of oxygen, can be unhealthy to breathe - particularly for children, people with respiratory problems or heart disease, and even healthy adults who work or exercise outdoors. Exposure to high ozone levels may cause previously healthy individuals to develop asthma over time. Ozone also causes millions of dollars in tree and crop damage each year. More than half of North Carolina's residents live in counties where ozone levels exceed the standard at times.

Particle pollution, which consists of very small particles and liquid droplets in the air, can be harmful to breathe and contributes to haze and other air quality problems. Fine particles can penetrate deeply into the lungs and absorb into the bloodstream, causing or aggravating heart and lung diseases. Persons most susceptible to particle pollution include those with heart and respiratory conditions, the elderly and young children.

Currently all of North Carolina meets federal particle standards, but levels have exceeded the annual standard in several Piedmont counties in the past. Unlike ozone, which is usually highest in the afternoons, particle levels can be high at any time of the day. Sensitive groups should take special care to limit their physical activity during high particle periods.

The DAQ developed its air quality forecasting system to help citizens better protect their health and to comply with clean air standards. In the Triad, forecasts are issued by the Forsyth County Environmental Affairs Department.

North Carolina has taken a number of steps to reduce levels of ozone, fine particles and other air pollutants in recent years. The General Assembly enacted the Clean Smokestacks Act, which requires power plants to reduce their ozone, particle and haze-forming emissions by three-fourths. Other legislation has required cleaner gasoline and expanded the auto emissions-testing program from nine to 48 counties.

Citizens can obtain air quality information and forecasts by visiting the DAQ's Web site at http://www.ncair.org or Forsyth County's Web site at http://www.co.forsyth.nc.us/EnvAffairs/. The division also has a toll-free hotline
(1-888-RU4NCAIR) where people can call to get the forecasts.

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