Grades 6-8
Section 2: Ambient Air Quality Standards
Ambient Air Monitoring Program
National Ambient Air Quality Standards
The NAAQS for Ozone and the Tulsa Area
Concerns about air quality are not a recent phenomenon. Some dates of interest in air quality history include:
1273 – London enacted the first smoke abatement law which prohibited the use of coal as “prejudicial to health.”
1307 – Edward I banned the use of sea coal in craftsmen’s furnaces due to foul smelling fumes.
1377—Chimney height was recognized as important in pollution dispersal, and London regulated their heights.
1772 – The start of the Industrial Revolution. But even before then, London had been experiencing fog (also called smog: smoke + fog) so thick it was difficult to see from one side of the street to another. With the start of the Industrial Revolution, pollution spread onto the European continent and to North America. Laws were passed in an attempt to regulate pollution but were mostly weak.
1873-80 – London was plagued with thick fogs containing SO2 and soot, referred to as “pea soup.” In December 1873, one episode caused 650 deaths. In Jan 26-29, 1880, London experienced a smog so severe, there were 1176 excess deaths reported. Severe smog episodes continued to plague London into the middle of the 20th century.
1881 – Chicago passed the first American smoke ordinance.
1901 – Oil was discovered in Red Fork, just south of Tulsa, forever changing its economic, industrial and environmental future.
1907-15 Resulting from a lawsuit filed by the State of Georgia, the US Supreme Court decided various major pollution lawsuits determining amounts of sulfur and other noxious fumes emitted from Tennessee Copper Co. Sulfur dioxide fumes from Copper Basin smelters in Tennessee were killing forests and orchards and making people sick in Georgia.
1939 – St. Louis smog episode so thick that lanterns are needed during daylight hours for a week.
1943 – First recognized episodes of Los Angeles smog.
1948 – Donora, Pennsylvania, pollution episode in October with several thousand ill and 20 deaths attributed to it. That same winter, London also experienced a smog episode with 700 – 800 deaths.
1950 – Research shows photochemical reactions are the source of Los Angeles smog.
1952 – London’s infamous smog episode, due to high SO2 levels and high amounts of suspended particulate matter, resulting in 4000 deaths. Also in 1952, Dr. Arie Haagen-Smit discovered that nitrogen oxides and hydrocarbons in the presence of ultraviolet radiation from the sun formed smog.
1953 – New York City experienced a pollution episode with many deaths. Also in 1953, Los Angeles County started a “Smoke School Program,” beginning the first standardization of “visible emission programs” nationwide.
1955 – Federal Air Pollution Control Act was enacted, providing for research and technical assistance and authorized the Secretary of Health, Education, and Welfare to work towards a better understanding of the causes and effects of air pollution.
1956 – Britain passed its Clean Air Act.
1963 – The first Federal Clean Air Act (CAA) was enacted. Air Quality criteria was defined based on scientific studies and funding grants were provided to state and local air pollution control agencies.
Also in 1963, an air pollution inversion in New York led to more than 400 deaths. This New York weather pattern reoccurred for a 4-day incident in 1965, causing 80 additional deaths.
1965 – The first Amendment of the 1963 Federal Clean Air Act, providing for direct federal government regulation of air pollution issues and directing the establishment of auto emission standards.
1969 – A presidential order created the Federal Environmental Protection Agency (EPA). Also in 1969, the first state Ambient Air Quality Standards were initiated by California.
1970 – The Federal Clean Air Act Amendments enacted, serving as the principal source and authority for controlling air pollution. They require states to develop State Implementation Plans (SIPs) demonstrating compliance with the Clean Air Act. Also in 1970, the first Earth Day, held April 22nd.
1971 – EPA promulgates the National Ambient Air Quality Standards (NAAQS). The Tulsa area does not meet the NAAQS for ozone.
1972 – California submitted its first State Implementation Plan to EPA, and it was rejected and sent back for re-development.
1977 – Tulsa Air Quality Measurement Study, sponsored by EPA to study ozone precursors, meteorological impacts, spatial distribution of ozone-forming pollutants, the relationship of volitile organic compounds (VOCs) to oxides of nitrogen (NOx), and to document ozone transport across the region. The first Tulsa Emission Inventory was developed.
1978 – The Tulsa City-County Health Department’s (TCCHD) Environmental Advisory Council proposed air quality recommendations, which became ordinances.
1984 – 85 - Tulsa City-County Health Department conducted an area Hydrocarbon Study, primarily to support required SIP modeling. The Tulsa Area Emission Inventory was refined and submitted to EPA in the 1985 SIP.
1988 – The Tulsa City-County Health Department conducted an oil field emission study, sampling ambient air to determine the influence of oil field emissions.
1989 – After a series of aggressive and effective air pollution control strategies, the Tulsa area was finally in compliance of the NAAQS and was designated clean, or in attainment of the ozone standard.
1990 – The Federal Clean Air Act Amendments passed by Congress authorized EPA to designate areas according to severity of non-compliance with the standards. Amendments included sanctions for the loss of federal highway funding in areas not in compliance with the NAAQS by the specified timeframe.
1991 – On June 24th, two of the three area ozone monitors exceeded the 0.124 ppm standard, causing concern and resulting in the development of the INCOG Air Quality Committee. Within two weeks, the Ozone Alert! Program was created by the just-formed Air Quality Committee and launched. The Tulsa City/County Health Department and ODEQ initiated O3 forecasting with public alerts by the Ozone Alert! Program. With the urgency and critical state of a NAAQS violation and near non-attainment status looming, the Ozone Alert! Program allowed industry, businesses and the community to voluntarily take action to reduce ozone-forming hydrocarbons on days when high levels of ozone are forecast. Tulsa’s Ozone Alert! Program was the first voluntary “take-action” program of its kind in the nation and has been replicated in many areas throughout the U.S.
1994 – INCOG sponsored a study of motor vehicle emissions to randomly sample vehicle Hydrocarbons and CO emissions with a remote sensing device located near tail pipe level. The findings were similar of other cities, in that a relatively small percentage of the card contributed most of the emissions.
1995 – Tulsa became the first “Flexible Attainment Region” (FAR) in the U.S. The FAR Program, developed by the INCOG Air Quality Committee, was a 5 year Memorandum of Agreement (MOA) with EPA Region VI to avoid re-designation as non-attainment for ozone while in the process of implimenting emission control measures, even though the standard may be violated.
1997 – EPA established new primary and secondary standards for ozone, based on an 8-our average ozone concentration rather than the current 1-hour average based standard.
1997 - The Tulsa Area Clean Cities Program was begun, the 57th in the nation, promoting the use of alternative fuels for transportation.
1999 – The Federal Court of Appeals for the D.C. circuit blocked EPA’s authority to impliment the new 8-hour ozone NAAQS.
2001 – US Supreme Court upheld the new 8-hour ozone NAAQS but ruled against EPA’s proposed implementation approach.
2002 –In the summer of 2002, the Tulsa area entered into an “Ozone Flex Plan” (O3Flex) with EPA Region VI. Through a memorandum of agreement with EPA, the O3Flex program provided the area with an “insurance policy” that a non-attainment designation would be postponed as long as numerous additional voluntary emission reduction control strategies are developed. A single 1-hour ozone exceedance at the Skiatook monitor during the 2002 ozone season would place the Tulsa area in violation of the 1-hour ozone standard. The Skiatook monitor remained exceedence-free during the 2002 ozone season.
2002 – December 23, 2002, The Tulsa Area Ozone Early Action Compact Agreement (EAC) was signed by INCOG, the City of Tulsa, the Metro Tulsa Chamber, the Oklahoma Department of Environmental Quality, and the U.S. EPA Region VI. The EAC will defer the effective date of non-attainment designation as long as all terms of the agreement are being met, or until specific selected control measures do not achieve attainment at the monitors in 2007.
In 1955 the U.S. government, recognizing that air pollution was a national problem, enacted the Air Pollution Control Act, the first federal legislation dealing with the problem. Its main purpose was to provide money to the Public Health Service to research air pollution and did little to actually prevent it. Amendments in 1960 and 1962 extended funding and called for research by the Surgeon General into the health aspects of air pollution.
The Clean Air Act of 1963 was the first U.S. attempt to control air pollution and for the first time recognized pollution hazards from mobile source (cars, trucks, etc) emissions as well as stationary (industry, fireplaces, etc.) sources. It was amended in 1965 to establish motor vehicle emission standards and to promote research into the problem of transboundary pollution into Canada and Mexico. Amendments to the CAA in 1967 divided the nation into Air Quality Control Regions for monitoring. National emissions standards for stationary sources were also set, with a fixed timetable.
By 1970 the environmental movement was in full force, pressuring the government to better regulate and control pollution. The federal government responded with a complete rewrite of the CAA. The new CAA set National Ambient Air Quality Standards (NAAQS, see page 33), strictly regulated new emissions sources and set standards for hazardous emissions, including those from motor vehicles. The Act also allowed the public to take legal action against any polluter, including the federal government. Overseeing environmental standards of the air, land, and water was the newly formed Environmental Protection Agency (EPA). The EPA was tasked with setting and enforcing environmental policies and standards and conducting environmental research.
The CAA was again amended in 1977 to extend deadlines for
motor vehicle emissions. The amendments also addressed, for the first
time, the issue of stratospheric ozone depletion.
Major changes in the CAA did not occur again until the Amendments of 1990, when EPA designated areas according to how severely they violated the NAAQS. In preparation for these Amendments, the Tulsa area underwent aggressive and strategic control strategies to meet the ozone standard. When the CAA revisions were passed in 1990, the Tulsa area was successfully designated in attainment of the NAAQS. Non-attainment classifications included specific control strategies and associated timetable requirements to achieve compliance with the standard. Also, automobile emissions standards were increased with these revisions. Use of low-sulfur and alternative fuels was encouraged to reduce the amount of acid rain.
The CAA requires that each ambient air standard is “revisited” at least every 5 years. As a result, in 1997 EPA issued revised ozone and particulate matter standards which were promptly challenged by various industry and political interest groups. These newer standards have been determined appropriate, more protective of the public health, and have recently become enforceable.
In 2002 President Bush announced the “Clear Skies Initiative” which is designed to dramatically reduce power plant emissions of sulfur dioxide (SO2), nitrogen oxides (NOx), and mercury by national caps on each pollutant at an average of 70% below today's levels.
Clear Skies is modeled on the cap-and-trade provisions of the 1990s and the Acid Rain program. Mandatory emission reductions would be achieved through federally enforceable emissions limits (or "caps") for each pollutant. Sources would be able to transfer these authorized emission limits among themselves to achieve the required reductions at the lowest cost.
Clear Skies would not replace the authority of state and local government to set source-specific emissions limits to ensure that ambient air quality standards will be met. Perhaps most importantly, Clear Skies would result in significant benefits to public health and the environment.
The Clean Air Act requires the Environmental Protection Agency to set National Ambient Air Quality Standards (NAAQS) for the six criteria pollutants defined in Section I. Pollutants are measured in units of parts per million (ppm), milligrams per cubic meter of air (mg/m3), and micrograms per cubic meter of air (µg/m3).
The chart on the next page lists the NAAQS for the criteria pollutants. There are two types of NAAQS: Primary standards, which set limits to protect public health, including the health of “sensitive” populations, such as asthmatics, children, and the elderly, and secondary standards, to protect public welfare, including protection against decreased visibility, damage to animals, crops, vegetation, and buildings.
In addition to the six criteria pollutants, the EPA also lists 188 Hazardous Air Pollutants (HAPs). These are less wide-spread than criteria pollutants, but they can cause serious health effects when people are exposed to them. Examples of HAPs include benzene (found in gasoline), perchlorethylene (used in dry cleaning), or metals such as mercury.
States have the major responsibility for enacting and enforcing EPA’s regulations. Due to the states’ knowledge of their regions, geology, industries, etc., they are responsible for carrying out the provisions of the CAA, such as issuing permits. In addition, states may issue their own pollution limits which may be stricter — but not weaker— than EPA standards. States are required to develop State Implementation Plans (SIPs) which are a collection of regulations detailing to the EPA how a state will implement and enforce pollution standards under the CAA. The EPA requires states to involve the public in developing SIPs. Once developed, each state sends its SIPs to the EPA, which reviews and approves each one. If the EPA decides a SIP is unacceptable, it has the power to directly enforce the CAA in that state.
The Air Quality Division (AQD) of the Oklahoma Department of Environmental Quality (ODEQ) is responsible for the implementation of state and federal CAA requirements for the Tulsa area. As part of this implementation, the ODEQ recommends adoption of rules, promotes compliance efforts, enforces rules, develops pollution prevention strategies to reduce emissions and improve air quality, and sometimes levies fines for violators. Additionally, the ODEQ provides for the development of the Oklahoma SIP.
Ambient Air Monitoring Program
The Clean Air Act, as amended in 1990, expanded and strengthened the EPA’s role in improving air quality nationwide. The EPA is charged with setting NAAQS, ensuring (in cooperation with the states) that standards set by the EPA are met, ensuring sources of toxic emissions are well controlled, and monitoring the effectiveness of the program. In order to do this, the EPA developed the Ambient Air Monitoring Program.
This program judges compliance and progress of states and communities toward meeting the NAAQS, activates emergency control procedures that prevent or alleviate air pollution episodes, observes pollution trends throughout the nation, and provides a database for research.
State and local governments are responsible for implementing and carrying out programs to improve air quality. Monitoring stations are located in and around localities in order to sample what is in the air.
The Oklahoma Monitoring Network consists of 62 monitors located at 37 sites throughout the state of Oklahoma. These monitoring stations routinely measure concentrations of the criteria pollutants (ozone, sulfur dioxide, nitrogen oxides, carbon monoxide, particulate matter 10, and particulate matter 2.5) in the ambient air in the Tulsa area. The map below of the Oklahoma Monitoring Network, identifies the locations of the monitors and the pollutants which are monitored at each site. Each monitor’s data can be viewed real-time on line at: http://www.deq.state.ok.us/AQDnew/monitoring/cpdata.htm
The monitoring stations fall into three categories: State and Local Air Monitoring Stations (SLAMS), National Air Monitoring Stations (NAMS), or Special Purpose Air Monitoring Stations (SPAMS). A fourth category was added after the 1990 CAA, Photochemical Air Monitoring Stations (PAMS), which monitor ozone precursors (primary pollutants that form ozone). Ozone pollution is monitored throughout the state by 20 monitoring stations, including three Tribal ozone monitors.
The ODEQ maintains five ozone monitoring stations in
Tulsa County, as indicated on the map. These monitors provide hourly
measurements of ground-level ozone.
The NAAQS for Ozone and the Tulsa Area
The Clean Air Act gives the EPA authority to establish national ambient air quality standards (NAAQS). In the Tulsa metropolitan area, the pollutant of greatest concern is ozone. As of 2003, the Tulsa area and the state of Oklahoma remain in attainment (not on the “EPA’s Dirty Air List”) of the NAAQS.
Areas are considered in violation of the 1- hour standard of 0.124 parts per million (ppm), when the 1-hour standard is exceeded at the same monitor more than once per year, when averaged for three consecutive years. The Tulsa metropolitan area is meeting the 1-hour ozone standard but has not consistently met the new federal 8-hour standard.
A new ozone standard was adopted by the EPA in 1997. The new standard provides increased protection to the public, especially children and other at-risk populations, against a wide range of ozone-induced health effects.
The new standard is an 8-hour averaged standard and is calculated by averaging data over a three-year time period. This average is taken from the fourth highest daily 8-hour average at each monitor. For example, the Skiatook monitor’s fourth highest 8-hour average was 0.096 ppm in 2000, 0.084 ppm in 2001, and 0.083 ppm in 2002. The current three-year average is 0.087 ppm (rounding does not apply). Since this number is greater than 0.084 ppm, the site has exceeded the new federal standard and the Tulsa metro area would be eligible for a non-attainment designation.
Though the Tulsa area violates the new 8-hour standard, due to numerous court challenges, EPA has only recently been given full release to impose it. Areas not meeting the new standard are not automatically designated non-attainment, rather an official course of action must occur. Specific requirements on how areas will meet the 8-hour standard are being developed, and designations are expected in spring of 2004. It is anticipated that both standards will remain enforceable and have some overlap before EPA revokes the 1-hour standard.
In a pro-active initiative to achieve cleaner air and meet the new 8-hour standard earlier than would be reached through a traditional non-attainment designation, the Tulsa area entered into an Ozone Early Action Compact (EAC) with EPA in December of 2002. The EAC assures that EPA will defer the effective date of non-attainment designation for the Tulsa area for a period up to 5 years or until an EAC milestone obligation becomes unmet.
Local, national, and even international TV meteorologists report an Air Quality Index. This index provides an easy-to-understand way to explain the quality of the air. Anything below a 100 Air Quality Index (AQI) is considered “healthy” and an AQI above 100 is considered “unhealthy for certain groups”. The ozone AQI is based on the new 8-hour standard. When the AQI is above 100, it is an indication of an exceedance of the air quality standards.
Air quality affects how we live and breathe. Like the weather, it changes from day to day and even hour to hour. To make information about outdoor air quality as available to the public as information about the weather, the EPA has developed the Air Quality Index (AQI). Through this tool, the Oklahoma Department of Environmental Quality, other states and local areas can provide the public with timely and easy-to-understand information on local air quality and whether air pollution levels pose a health concern.
The Air Quality Index (AQI) is an index for reporting daily air quality. It tells how clean or polluted the air is, what associated health concerns one should be aware of, and suggest actions to take when pollutants reach unhealthy levels. The AQI focuses on health effects that can happen within a few hours or days after breathing ambient concentrations of any of five pollutants regulated by the Clean Air Act: ground level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen oxides.
The AQI, like a measuring stick, runs from 0 to 500. The
lower the number, the better the air quality, with 100 representing the
national standard for that pollutant. Consequently, AQI values below 100
represent generally satisfactory air quality and little potential to
affect public health. 
The Tulsa area has not seen AQI values over 300, which represents hazardous air quality. Further, the AIQ scale is divided into six color-coded categories. Therefore, an AQI of 45 falls in the green zone, indicating good air quality. But a value above 300 falls in the maroon zone, indicating hazardous conditions.
Air monitoring stations across the Tulsa area, Oklahoma and the nation collect raw data for each of the five criteria pollutants. The raw measurements are then converted into AQI values using standard formulas developed by EPA and calculated for each of the individual pollutants in an area. The highest of the AQI values becomes the AQI value for that day and is reported to the public.The AQI scale is as below:
The AQI value is the highest AQI value of any of the pollutants for that day. Therefore, if on a given day Tulsa has an AQI of 90 for ozone and an AQI of 88 for particulate matter, the AQI would be 90, due to ozone, and the index color would be yellow. The health-based message which accompanies a yellow AQI of 90 due to ozone is “Moderate; Unusually sensitive people should consider limiting prolonged outdoor exertion.”
Each pollutant has unique cautionary statements associated with each of the six levels of health concern categories.
Since the AQI is a national index, the values and colors used to show local air quality and the associated level of health concern will be the same throughout the U.S. In large metropolitan areas (more than 350,000 people), state and local agencies are required to report the AQI to the public daily. Especially during the summer ozone season, the AQI is also reported in local area newspapers, on television and radio, and on the internet.
Finally, the AQI is not only a tool to report the current conditions of the air quality, it can additionally be used as an air quality forecasting tool for the next day’s potential conditions.
AQI information for Tulsa can be found at EPA’s AirNow website (http://www.epa.gov/airnow) . This website contains real-time and forecast data for ground level ozone in the Tulsa area as well and the rest of the nation. The Oklahoma Department of Environmental Quality’s website (http://www.deq.state.ok.us/AQDnew/AQIndex/AQI.htm) also provides the AQI for our area and other areas in the state.