The EPA maintains a system of rating the safety of the air in a given area, called the Air Quality Index. Understanding the Air Quality Index is important because it gives people vital information about the conditions of the air in their location and how the quality of the air in their city can impact their health. How does the EPA’s Air Quality Index work?
Why The Air Quality Index Is Needed
“The air quality index is needed to provide a metric for warning citizens about the dangers of air pollution at varying levels of intensity,” says Kevin Wood, Vice President Sales & Marketing
at Camfil USA. “Air pollution is one of the primary causes of health ailments and premature death in the world. The World Health Organization estimates that ambient outdoor air pollution kills around three million people every year.” (1)
The most common air pollutants found outdoors include what the EPA categorizes as criteria air pollutants. These criteria air pollutants are ground-level ozone, particulate matter, lead, carbon monoxide, nitrogen dioxide and sulfur dioxide.
Ozone pollution comes from the emission of volatile organic compounds (VOCs) that interact with sunlight and heat to form ground-level ozone, a key ingredient of smog. Ozone pollution can irritate the eyes, nose, and throat and do lasting to people’s lungs.
“Particulate matter air pollution consists of fine particles, smaller than 2.5 microns in size, that are small enough to penetrate people’s lungs and bloodstream. Particulate matter pollution can cause or exacerbate heart and lung conditions and increase a person’s chance of developing lung cancer,” explains Wood. (2)
Both sulfur dioxide and nitrogen dioxide are emitted by industrial facilities and cars. They can exacerbate respiratory ailments like asthma, and are thought to be contributors to asthma and air pollution-related visits to the emergency room. High levels of exposure can reduce lung function permanently.
Carbon monoxide is released into the air primarily by the incomplete combustion of fossil fuels. Carbon monoxide is colorless and odorless, and when inhaled in large amounts it can easily lead to confusion, dizziness, and death.
Though levels of atmospheric lead have decreased by around 98% since 1980, lead can still be found in the atmosphere and exposure to it can cause a variety of problems. Lead can impact kidney function, the entire nervous system, the immune system, and lead to developmental problems in children.
Due to the dangers of ambient air pollution, a system for warning citizens about abnormally high and dangerous levels of ambient air pollution is necessary.
How The Air Quality Index Works
“The Air Quality Index works by assigning the air in a particular geographic area one of six different rankings, depending on the level of atmospheric air pollutants present in the region’s air,” says Wood. “The rankings run from Good air quality to Hazardous air quality. Each ranking has a corresponding number value as well as a color.” (3)
The first ranking in the AQI represents Good air quality, is represented by the color green, and contains the values 0 to 50 in its range. Air found in the Good category poses little to no risk for the health of the general population.
The second category of the AQI contains acceptable or Moderate air quality, and it is represented by the color yellow. It contains the values 51 to 100 and means that the air is generally safe, but those who are sensitive to air pollution should be cautious, as they may experience respiratory symptoms.
The third category of the AQI represents air that is “unhealthy for sensitive groups,” and is symbolized by the color orange. It contains the values 101 to 150 and it means that although the general public is not likely to be negatively impacted by the air, sensitive groups like older adults and children are at risk from exposure to particles present in the air.
Section four of the AQI is symbolized by the color red and denotes air that is Unhealthy. It contains the values 151 to 200, and at this level, the air can start having adverse health effects on the entire population, while people and sensitive groups can experience much more serious effects. A recent example of elevated AQI within this range was the wildfires prevalent this year in California. In many areas, it was recommended that residents wear filter masks to prevent breathing the contaminated air from the wildfires, sometimes carried hundreds of miles by atmospheric winds.
The fifth section of the AQI is denoted by the color purple, and it contains the values 201 to 300. This ranking means that the air is Very Unhealthy, and the entire population can experience more severe health impacts.
The final section of the AQI is denoted by the color maroon, and it contains the values 301 to 500. Air in this range is categorized as Hazardous, and at this level, an emergency alert would usually be broadcast about the hazardous conditions. The entire population is likely to be affected by the air quality, and immediate steps should be taken to protect oneself from the air as it can quickly cause health problems.
Understanding The Air Quality Index and Using It
Understanding the air quality Index and using it to protect yourself means staying up-to-date on air quality forecasts for your specific location. Depending on the air quality index for your geographical location, you will want to take different steps to protect your health.
At the first couple levels of the AQI, it is unlikely that you will need to take special precautions to protect your health unless you suffer from preexisting respiratory conditions.
Starting at the “unhealthy for sensitive groups” and continuing into the Unhealthy category, you should start taking precautions to protect yourself, especially if you are sensitive to air pollutants. You should limit your activity outdoors if you can, and if you must be outside, do so late in the day or early in the morning when air pollution levels are at their lowest.
“At the Very Unhealthy and Hazardous levels, you should limit time spent outdoors if possible, only going out when it is absolutely necessary,” says Wood. “Stay away from freeways and major centers of traffic, and go out when pollution levels are lowest. You can employ industrial grade facemasks to limit the amount of pollution you breathe. You will also want to invest in quality air filters and purifiers for your home, and as always understanding the air quality index is critical for your health.” (4)
Understanding the Air Quality Index is important because it keeps you informed about how to protect your health. Camfil can provide you with the filters you need to protect your health when air pollution is at its worst, or at any time, so contact Camfil USA for your air filtration needs today.
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