时差N小时 空气洁净法令（在线收听）

The first time Congress dealt with any issue pertaining to unclean air was in 1955. Prior to that, states had passed their own legislation dealing with the problems of impure air… most of it excess smoke from burning fields and clearing forests. But as industry and our nation grew, more people and more land were exposed to dirty air emissions from industrial smokestacks and automobile exhaust.

国会处理关于空气污染的问题始于1955年。在此之前，各州自己制定法律，用以解决空气污染问题。过量的烟雾大多产生于田地燃烧和森林砍伐。但随着工业发展，国力增强，越来越多的人和土地暴露在工业烟囱和汽车排放的污浊空气中。

By the 1960s, environmental issues had become a public concern, as scientific studies linked air pollution to specific health issues. The Clean Air Act of 1963 marked the beginning of federally funded air quality research programs to deal with increasing amounts of smog. Two years later, it was amended to include cars as a source of pollution. The Clean Air Act of 1970, the year the EPA was established, was even more robust, and subsequent amendments in 1977 and 1990 addressed ozone depletion and acid rain.

到1960年，环境问题备受公众关注，科学研究也将空气污染与具体的健康问题联系起来。1963年的空气洁净法令成为联邦政府提供资助，进行空气质量研究以处理日益增加的烟雾的开端。两年后，这项法案的修正案将汽车纳入污染源范畴。环保署成立那年颁布的1970年空气洁净法令内容更加充实。1977以及1990年的后继修正案中重点提到了臭氧层破坏和酸雨的危害。

Enforcing clean air standards has helped control pollution and reduce health hazards over the years, but the process of improving and amending this Act to keep our air clean is on—going, as the costs to industry must be weighed against the benefits to the environment. The Clean Air Act—one of the most complex and extensive pieces of federal environmental legislation—remains very much a work in progress.

近年来，洁净空气法规的实行在控制污染和减少对人类健康的危害方面起到促进作用。然而，改进、修订这条法令的进程还在继续，因为良好环境带来的好处必须要与工业的损失相抗衡。作为联邦环境法律中最复杂，范围最广的条例，空气洁净法令还在如火如荼地进行着。