Air quality alerts are a public health communication tool used by environmental agencies to inform the public about immediate environmental risks. These alerts prompt communities to take necessary precautions against harmful atmospheric conditions. The system uses the standardized Air Quality Index (AQI), which provides a simple, color-coded way to understand air quality, especially for those susceptible to pollution effects.
Understanding the Air Quality Index
The Air Quality Index (AQI) is a standardized, color-coded scale used by the U.S. Environmental Protection Agency (EPA) to report daily air quality, ranging from 0 to 500. This scale communicates how clean or polluted the air is and what associated health effects might be a concern. An AQI value of 100 corresponds to the national air quality standard, meaning values at or below 100 are considered satisfactory.
The scale is divided into six color-coded categories, each representing a different level of health concern. Green (0 to 50) signifies “Good” air quality, posing little risk. Yellow (51 to 100) is “Moderate,” where air quality is acceptable but may present a slight risk for people sensitive to pollution. Once the AQI exceeds 100, the air quality is considered unhealthy, first for sensitive groups, and then for everyone as the numbers climb higher.
The Specific Meaning of Code Orange
A Code Orange alert corresponds to an Air Quality Index range of 101 to 150. This level is officially categorized as “Unhealthy for Sensitive Groups,” meaning pollutant concentration has surpassed the federal standard. While the general public is not likely to be seriously affected, sensitive groups may experience adverse health effects.
Code Orange air quality is typically driven by elevated concentrations of two primary pollutants: ground-level ozone and fine particulate matter (PM2.5). Ground-level ozone forms when emissions from vehicles and industrial sources react in the presence of sunlight and hot weather. PM2.5 consists of microscopic particles that can come from sources like vehicle exhaust, industrial emissions, or wildfire smoke, and these pollutants can penetrate the respiratory system.
Health Risks for Sensitive Groups
Sensitive Groups include individuals susceptible to air pollution effects, such as children, older adults, and people with pre-existing medical conditions. Those with chronic lung conditions like asthma, emphysema, or Chronic Obstructive Pulmonary Disease (COPD) are at heightened risk. People with heart disease and diabetes are also included in this vulnerable population.
Exposure to Code Orange air quality primarily affects the respiratory system. Pollutants like PM2.5 and ozone cause airway inflammation, leading to coughing, wheezing, and shortness of breath. This can increase the frequency and severity of asthma attacks for individuals with asthma. Healthy children are also at elevated risk because they spend more time active outdoors and inhale more air relative to their body weight.
Actionable Steps During an Alert
When a Code Orange alert is issued, sensitive groups must reduce exposure to outdoor air. This involves limiting or rescheduling strenuous outdoor activities, especially during the late afternoon when ozone levels are highest. Children and those with respiratory conditions should avoid outdoor physical activity entirely.
The public should take steps to improve indoor air quality:
- Keep windows and doors closed to prevent polluted air from entering indoor spaces.
- Use an air conditioner set to recirculate the air.
- Invest in a portable air cleaner with a HEPA filter.
- Monitor symptoms closely and ensure necessary medications are readily available.
- Seek medical attention if difficulties such as chest pain or unusual fatigue occur.