22h 28min, nov 30, 1963 y - By the time President Lyndon Johnson signed into law the first Clean Air Act in December 1963 it was later amended in 1966, 1970, 1977, and 1990—America's air had been under siege for decades.
Description:
Clean air actAdded to timeline:
Date:
22h 28min, nov 30, 1963 y
Now
~ 61 years ago