Few things have had a greater influence on the design and engineering of modern automobiles than emissions control regulations. First initiated in California in the fifties and sixties, legislative and regulatory efforts to limit motor vehicle emissions soon became a model for U.S. federal standards, which in turn helped to shape environmental law in other countries. In this installment of Ate Up With Motor, we present a timeline of the major early events and developments in governmental control of auto emissions, from the 1940s through the end of the 1960s.

San Gabriel, Los Angeles County, California, in May 1972. (Photo: “LOW-HANGING SMOG” by Gene Daniels / Environmental Protection Agency via the National Archives and Records Administration; in the public domain in the United States)

Continue Reading Before the Muskie Act: Early Emissions Law and Regulation, 1940–1969