Air Quality
OZONE ADDS INSULT TO INJURY
With the approach of summer, asthma sufferers can look forward to breathing more easily as the pollen counts drop. But just when you thought it was safe to go outdoors again, the meteorologist announces a more ominous warning: “Tomorrow is an ozone alert day”. For those of you who are newcomers to the D/FW area and are not familiar with this scourge of the big city, this announcement would be more aptly rephrased: “HEY, YOU PEOPLE WITH ASTHMA OUT THERE, BREATHING OUTDOORS MAY BE HAZARDOUS TO YOUR HEALTH!” Well, that may be a bit over exaggerated; however, people with asthma and other chronic respiratory conditions should be aware of the potential for breathing problems associated with exposure to high levels of ozone.
The air pollutant ozone should not be confused with the protective ozone layer which is found in the 
earth’s upper atmosphere. That layer helps us maintain stable temperatures and shields us from some of the more harmful rays of the sun. Ozone found in the air we breathe at ground level is a major component of smog, formed by the action of sunlight upon automobile and industrial emissions. Thus, ozone levels generally peak in the months of July to September, when there is plenty of sunshine and a lack of wind to clear the air. Ozone levels are usually higher during the late afternoon hours compared to the early morning or late evening.
The degree to which ozone may affect your breathing depends on the amount of ozone in the air, your level of activity and the length of time you spend outdoors. Ozone breathed in concentrations exceeding 0.12 parts per million (ppm) is considered unhealthy according to Environmental Protection Agency standards. At this level, persons with asthma may experience cough, wheezing or chest tightness with light to moderate outdoor exercise. More severe symptoms may occur with heavy outdoor exercise at this level or with prolonged exposure to higher levels of ozone.
In order to reduce the risks of breathing problems associated with ozone exposure, you should try to limit your level of outdoor activity and time spent outdoors on ozone alert days, particularly during the late afternoon hours when ozone levels are highest. This might be a good time to take up indoor swimming or aerobics to maintain cardiovascular fitness without aggravating your asthma. Taking a vacation away from the city (and away from other major cities) this time of year could make ozone avoidance very enjoyable. If your work requires outdoor activity during the hot summer months, consider wearing a charcoal-filtered face mask if this is practical for you.
Now that you know the hazards of ozone exposure, you can make appropriate adjustments in your schedule and lifestyle to avoid this potential asthma trigger. It’s as simple as remembering to carry an umbrella to avoid getting wet when the forecast calls for rain. Have a safe and fun summer!
OZONE FORECAST EMAIL SIGN UP WITH TEXAS NATURAL RESOURCES CONSERVATION COMMISSION OR MAY VIEW DAILY FORECAST AT:
http://www.tceq.state.tx.us/cgi-bin/compliance/monops/aqi_rpt.pl