What Is An Air-Quality Alert?
Whether changes on a daily basis. So too does the air quality, particularly during the warmer summer months. Noting the air quality during the summer is important because air quality is related to how clean and/or how potentially unhealthy the air is breathe, which is a major health concern for some. For this reason, the U.S. Environmental Protection Agency (EPA) as well as the National Weather Service (NWS) has created a system of public advisories that alerts the public to the quality of the air during warm weather forecasts. When the quality of air becomes a factor, local, regional, or national offices of the NWS will issue forecasts containing variations of the phrases, air-quality alert, ozone-alert, or ozone- action days (previously explored briefly in the post, “Everything You Need To Know About Hot Weather (And Extreme Heat) Safety…”)
Air-Quality Day (“Ozone-Action Day”)
Whenever the quality of the air over a certain area or region is under the threat of rising to alert-worthy or even dangerously unhealthy levels, the EPA and/or the NWS will issue an Air-Quality Alert for that affected region. An air-quality (or “ozone action alert”) day is a public alert issued whenever the quality of the air becomes affected by certain present factors, that may adversely affect the health of those living under the alert, particularly those with preexisting health concerns.
What Determines an Air-Quality Alert Day?
What triggers an air-quality alert day? This particular type of alert is triggered by the either the presence or increase of two major environmental factors that contribute to air pollution:
• Ground-Level Ozone– High-levels of ground-level ozone are frequently the cause of air quality alerts. Ozone, particularly at the surface level, is formed when pollutants such as car exhaust and industrial output (i.e., fumes) mixes with the oxygen in the air. Air-quality alerts of this type tend to occur on hot, dry sunny days with a light breeze. The presence of ground-level ozone can trigger asthma attacks and decrease our lungs’ ability to function at optimum levels.
• Particulate Matter – Particulate matter consists of pollutants such as dust, soot, ash and smoke. The presence of these particles is often caused by the burning of fossil fuels (such as wood), or other chemical processes. This type of air quality issue is most common on hot, humid days. When this matter accumulates in the air we breathe, it can cause can cause difficulty in breathing, asthma attacks, and lung damage…especially in the elderly.
A key tool in this effort is the Air Quality Index, or AQI. The EPA and /or local offices of the NWS use the AQI to alert the public with information about the air quality for a given region.
The Air-Quality Index
The Air-Quality Index (or AQI) is an index for conveying to the public the quality of air over an area of concern, particularly during days where there is an increase in aggravating foreign matter present in the environment. It informs the pubic how clean or polluted the air is, and what associated health effect might be an issue for concern. The AQI focuses on health effects individuals might experience within a few hours or days after breathing polluted air. AQI is based on calculations that take into account the presence of five major air pollutants regulated by the EPA. In addition to the previously mentioned ground-level ozone and particulate matter (also known as “particle pollution”), the AQI also measures various amounts of carbon monoxide, sulfur dioxide, and nitrogen dioxide in the air. For each of these pollutants, officials have established national air quality standards to protect public health.
The purpose of the AQI is to help the public understand what the local air quality means in relation to those at-risk for respiratory-related health concerns. To make it easier to understand, the AQI is divided into six levels of health concern:
Using the AQI, those at-risk for respiratory health-related concerns should be able to plan their daily activities around the potential threat level. These at-risk individuals/groups include:
• Individuals with pre-existing respiratory conditions, such as asthma and emphysema.
• Young children, including those in their early teens (because their lungs are still developing and they breathe more air per pound of body weight than adults).
• The elderly.
• Individuals engaging physically-strenuous outdoor activities (such as athletes and those who work outdoors).
Using the guidelines established by the AQI, those healthy as well as those at-risk for aggravating conditions can plan to take steps to reduce both concerns as exposure to unhealthy air during air-quality alerts. These steps include:
• Choosing less-strenuous activities.
• Increasing the frequency of breaks during outdoor activity.
• Rescheduling activities, or confining activities to early morning hours, or postponing them for another day.
• Consider moving activities indoors, where ozone levels are usually lower.
Finally, there are steps that individuals can take to decrease the levels of ozone during air-quality alert days:
• Turn off lights unused lights and appliances.
• Drive less: carpool, use public transportation, bike or walk.
• Keep automobiles engine tuned, and avoid engine idling.
• When refueling, stop pumping when the pump shuts off, avoid spilling fuel, and tighten fuel container (and tank) cap.
• Inflate vehicle tires to the recommended air pressure.
• Seal and cleaning products, paints, and/or other items that create vapors that can evaporate into the air…to prevent evaporation on hot days.
• Watch for Air Quality Action Days in your area.
Lastly, in addition to monitoring the local forecasts for air-quality alerts, the EPA maintains a website that monitors and provides up-to-the-minute information of the air quality for every region of the country. Just click on the map, or pick the appropriate category for forecasts and/or current individual AQI’s for details (click: EPA).
- The No-Nonsense Guide To Heat Wave, Drought, & Hot Weather Safety (Enhanced Edition) by Jeffery
Publications like the "No-Nonsense Guide To Heat Wave, Drought, & Hot Weather Safety" can provide even more safety tips--as well as more information on how to stay safe in hot weather. Also in e-book format