Ozone Action Day
Encyclopedia
An Ozone Action Day, which can be declared by a local municipality, county or state, is observed at certain times during the summer
months, when weather
conditions (such as heat, humidity, and air stagnation
) run the risk of causing health problems.
Ozone Action Days, alternately called an "Ozone Alert" or a "Clean Air Alert", primarily center in the midwestern portion of the United States
; particularly in well-urbanized areas such as Chicago
, Cleveland, Detroit, and Indianapolis
.
found at the Earth's surface is the same chemical species as that found in the ozone layer
, they have very different sources, atmospheric chemistry, and affect human health differently as well. The ozone layer protects people from the sun's most damaging ultraviolet rays. Because the ozone layer is located high in the atmosphere, people are not directly exposed to it.
Ground-level ozone, however, is a health hazard because people breathe it. It is formed through a complex set of chemical reactions involving hydrocarbons, nitrogen oxides and sunlight on calm summer days where the weather may also be warm and humid http://www.epa.gov/ARD-R5/naaqs/o3info.htm. High levels of ground ozone affects the breathing process and aggravates asthma
in chronic sufferers. The young, elderly, and those with lung diseases are especially suspectible.
Ozone is most likely to exceed safety limits from May through October when seasonal heat and sunlight are at their highest http://www.setrpc.org/index.php?option=com_content&task=view&id=123&Itemid=217. However, similar conditions can occur at other times of the year in specific urbanized areas; namely the Los Angeles
area, which is well-known for smog
formation.
-fired power plants). Therefore, Ozone Action Days occur most frequently in the Midwestern United States. In recent years, many sites have taken steps to help reduce the amount of pollutants they discharge.
Secondary sources include automotive emissions (leaky auto exhaust systems, excessive engine idling) and liberal use of household chemicals or sprays. It is believed that nearly fifty percent of pollutant ozone molecules are attributed to the presence of these http://www.epa.gov/ARD-R5/naaqs/o3info.htm.
(AQI). The AQI is divided into six levels: the higher the number (on a 0-300 scale), the more severe the ozone threat Air quality index
.
Basic steps in limiting ground ozone during Ozone Action Days are:
Summer
Summer is the warmest of the four temperate seasons, between spring and autumn. At the summer solstice, the days are longest and the nights are shortest, with day-length decreasing as the season progresses after the solstice...
months, when weather
Weather
Weather is the state of the atmosphere, to the degree that it is hot or cold, wet or dry, calm or stormy, clear or cloudy. Most weather phenomena occur in the troposphere, just below the stratosphere. Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate...
conditions (such as heat, humidity, and air stagnation
Air stagnation
Air stagnation is a phenomenon which occurs when an air mass remains over an area for an extended period of time. Due to light winds and lack of precipitation, pollutants cannot be cleared from the air, either gaseous or particulate...
) run the risk of causing health problems.
Ozone Action Days, alternately called an "Ozone Alert" or a "Clean Air Alert", primarily center in the midwestern portion of the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
; particularly in well-urbanized areas such as Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...
, Cleveland, Detroit, and Indianapolis
Indianapolis
Indianapolis is the capital of the U.S. state of Indiana, and the county seat of Marion County, Indiana. As of the 2010 United States Census, the city's population is 839,489. It is by far Indiana's largest city and, as of the 2010 U.S...
.
Surface ozone vs. the ozone layer
Although the ozoneOzone
Ozone , or trioxygen, is a triatomic molecule, consisting of three oxygen atoms. It is an allotrope of oxygen that is much less stable than the diatomic allotrope...
found at the Earth's surface is the same chemical species as that found in the ozone layer
Ozone layer
The ozone layer is a layer in Earth's atmosphere which contains relatively high concentrations of ozone . This layer absorbs 97–99% of the Sun's high frequency ultraviolet light, which is potentially damaging to the life forms on Earth...
, they have very different sources, atmospheric chemistry, and affect human health differently as well. The ozone layer protects people from the sun's most damaging ultraviolet rays. Because the ozone layer is located high in the atmosphere, people are not directly exposed to it.
Ground-level ozone, however, is a health hazard because people breathe it. It is formed through a complex set of chemical reactions involving hydrocarbons, nitrogen oxides and sunlight on calm summer days where the weather may also be warm and humid http://www.epa.gov/ARD-R5/naaqs/o3info.htm. High levels of ground ozone affects the breathing process and aggravates asthma
Asthma
Asthma is the common chronic inflammatory disease of the airways characterized by variable and recurring symptoms, reversible airflow obstruction, and bronchospasm. Symptoms include wheezing, coughing, chest tightness, and shortness of breath...
in chronic sufferers. The young, elderly, and those with lung diseases are especially suspectible.
Ozone is most likely to exceed safety limits from May through October when seasonal heat and sunlight are at their highest http://www.setrpc.org/index.php?option=com_content&task=view&id=123&Itemid=217. However, similar conditions can occur at other times of the year in specific urbanized areas; namely the Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...
area, which is well-known for smog
Smog
Smog is a type of air pollution; the word "smog" is a portmanteau of smoke and fog. Modern smog is a type of air pollution derived from vehicular emission from internal combustion engines and industrial fumes that react in the atmosphere with sunlight to form secondary pollutants that also combine...
formation.
Sources of ground ozone
A major cause of the conditions is due to pollutants in the air released by heavy industry (manufacturing plants, refineries, coalCoal
Coal is a combustible black or brownish-black sedimentary rock usually occurring in rock strata in layers or veins called coal beds or coal seams. The harder forms, such as anthracite coal, can be regarded as metamorphic rock because of later exposure to elevated temperature and pressure...
-fired power plants). Therefore, Ozone Action Days occur most frequently in the Midwestern United States. In recent years, many sites have taken steps to help reduce the amount of pollutants they discharge.
Secondary sources include automotive emissions (leaky auto exhaust systems, excessive engine idling) and liberal use of household chemicals or sprays. It is believed that nearly fifty percent of pollutant ozone molecules are attributed to the presence of these http://www.epa.gov/ARD-R5/naaqs/o3info.htm.
Notification
State, county, and even local governments can announce Ozone Action Days as much as a day in advance through the monitoring of approaching weather conditions and the Air Quality IndexAir Quality Index
Air quality is defined as a measure of the condition of air relative to the requirements of one or more biotic species or to any human need or purpose. Air quality indices are numbers used by government agencies to characterize the quality of the air at a given location...
(AQI). The AQI is divided into six levels: the higher the number (on a 0-300 scale), the more severe the ozone threat Air quality index
Air Quality Index
Air quality is defined as a measure of the condition of air relative to the requirements of one or more biotic species or to any human need or purpose. Air quality indices are numbers used by government agencies to characterize the quality of the air at a given location...
.
What can be done
Heavy industries make up a high percentage of pollutants causing ground ozone. Without drastically altering or eliminating industrial production in an area altogether, air quality improvements are very slight, though noticeable. Non-industrial pollutants, while not thought of to be a major pollutant group, can be more controlled with more positive change occurring.Basic steps in limiting ground ozone during Ozone Action Days are:
- Controlling of auto emissions
- Eliminate excessive engine idling
- Ensure automotive exhaust system functions properly
- Avoid unnecessary driving whenever possible
- Don't refuel until after 6:00 pm
- Take public transportation (Cities such as Toledo provide free bus service on Ozone Action Days).
- Limit the use of lawn mowers and outdoor grills to after 6:00 pm
- Limit the use of aerosolAerosolTechnically, an aerosol is a suspension of fine solid particles or liquid droplets in a gas. Examples are clouds, and air pollution such as smog and smoke. In general conversation, aerosol usually refers to an aerosol spray can or the output of such a can...
cans around the home (for example, hair gelGelA gel is a solid, jelly-like material that can have properties ranging from soft and weak to hard and tough. Gels are defined as a substantially dilute cross-linked system, which exhibits no flow when in the steady-state...
instead of hair spray)
External links
- E.P.A. Government website which describes an Ozone Mapping Project for the Midwest
- Smart Communities Network website listing strategies, state ordinances, additional articles and resources
- Vast link page to various worldwide sites on general air pollution, pollution monitoring, and the environment - courtesy Louisville (KY) Metro Air Pollution Control District
- Tulsa's Ozone Alert Oklahoma pollution gallery, alerts, and information
- Ozone Prevention success stories - Georgia-based website