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Intense heat can lead to more than a drought. It can also cause unhealthy air due to ozone and other pollutants trapped by stagnant atmospheric conditions; medical emergencies due to exposure to high temperatures; increased chance of wildfires; and increased chance of losing electricity. Make sure your organization is ready to take the heat.
Urban areas are especially susceptible to the way excessive heat affects air quality. Stagnant atmospheric conditions during high temperatures can trap ozone and other pollutants near the ground. Because pollutants are concentrated in urban areas, people living in or near cities are particularly susceptible. Health risks associated with decreased air quality ("ozone days") include difficulty breathing and, in extreme cases, asthma attacks.
Local broadcast and newspaper ozone alerts generally correspond to the federal standards described below.
| Ozone Index Value | Precaution | |
|---|---|---|
| 0-50 Green: good |
Best for outdoor activity. | |
| 51-100 Yellow: moderate |
Unusually sensitive people should consider limiting prolonged outdoor exertion. | |
| 101-150 Orange: unhealthy for sensitive groups |
Active children and adults, and people with respiratory disease such as asthma, should limit prolonged outdoor exertion. | |
| 151-200 Red: unhealthy |
Exercise early/late; indoors when possible. Everyone, especially children, should avoid (if sensitive) or limit prolonged outdoor exertion. | |
| Above 200 Purple: very unhealthy |
Active children and adults, and people with respiratory disease such as asthma should avoid all outdoor exertion. Others should limit outdoor exertion. |
More information on ozone alerts can be found at the National Institute of Environmental Health Sciences Web site.
During periods of excessive heat, it is essential to listen to a NOAA weather radio or your local TV or radio station to monitor weather conditions, especially if you or your employees work outside. Make sure you know what the following terms mean.
Seniors, small children, chronic invalids, individuals taking certain medications or drugs (especially tranquilizers and anticholinergics) and persons with weight and alcohol problems are particularly susceptible to heat reactions. Some common heat-related illnesses include sunburn, heat exhaustion and sunstroke. Learn more about these and other heat-related illnesses, and how to treat them when they occur in the Responding section of this site.
Read about responding to heat-related emergencies.
