History of Visible Emissions Observations in the United States

History of Opacity Observations in Table Format

YEAR		MILESTONE
1859		First successful court case in U.S. regarding emissions was in New Orleans in 1859 against a blacksmith, stating that odors and smoke from the business was a nuisance.
1881		First two U.S. cities to adopt smoke control ordinances Chicago and Cincinnati
1897		U.S. begins to use Ringelmann Scale. Ringelmann had developed his work in the 1870s in France.
1910		U.S. Bureau of Mines forms
In the early 1900's, many court cases arose citing smoke as a nuisance.
1910		Rochester, NY - statute upheld the use of Ringelmann. Restrictions were placed on smoke production with limits on how long dense smoke can be produced.
1912		Of the 28 U.S. cities with populations of over 200,000, 23 cities now had smoke ordinances.
1916		Northwestern Laundry vs. Des Moines. Important case that upheld the right of the city to declare dense smoke in portions of the city a public nuisance.
1948		After pollution related deaths and illness in Donora, PA, U.S. Surgeon General declares smoke and other pollutants as a health hazard. This resulted in funding for air pollution studies.
By the end of the 1940's, smoke and air pollution are recognized as health hazards.
1950		California passes California Rule 50A to limit smoke emissions. This rule was used by a majority of U.S. states and was included in the NSPS in 1970.
1953		First smoke school in Los Angeles County, using equivalent opacity method.
1953		Equivalent opacity was added to the Ringelmann system by the Los Angeles Air Pollution Control Board. This allowed for measuring emissions in colors other than black (Ringelmann scale only uses percent of black).
1955		Federal Air Pollution Act - the first federal pollution control act
1963		Initial Clean Air Act passed by U.S. congress. Provided funding to air pollution control agencies.
1967		Federal Air Quality Act. Required states to establish Air Quality Regions and adopt Ambient Air Quality Standards (precursor to State Implementation Plans (SIPs).
1968		Join study by industry and government released by the Federal Air Pollution Control office: AP-30, Optical Properties and Visual Effects of Smoke-Stack Plumes.
1970		The U.S. Environmental Protection Agency (EPA) was formed on December 2.
1970		Clean Air Act updated 1970 - this formed the basis of the U.S air pollution policies.
1974		Method 9 was promulgated by the EPA and is still in use today.
1977		Additional amendments to the Clean Air Act.
1982		Method 22 for fugitive emissions was promulgated by the EPA.
By the end of the 1980's, Method 9 had effectively corrected excessive opacity/particulate emissions from most facilities.
1990		1990 Clean Air Act amended to include Title V. Title V was developed to create a uniform national permitting system Simply stated, this required companies that create air pollutants to obtain a permit.
In 1997, Title V began to shift focus from enforcement to maintenance of air qulity through continued use of Method 9.

SOURCES: EPA Visible Emissions Student Manual »
EPA Visible Emissions Field Manual »