Puzzle #484 · September 28, 2026
clean air
Featured
Every day one two-word expression or compound word used in American English.
Clean air isn't just the literal meaning of non-dirty air. The phrase “clean air” was central to the first environmental regulations in the US and UK.
The Great Smog of London in 1952 killed approximately 6,000 people in a week. The fog was so thick you couldn't see your hand in front of your face. The city essentially stopped functioning. By 1956, the British government passed the Clean Air Act—the first major environmental protection law in the world.
Eighteen years later, on December 31, 1970, President Nixon signed the American Clean Air Act with overwhelming bipartisan support—it passed the Senate unanimously and the House 374-1. The EPA was established to enforce it. The law required a 90% reduction in major air pollutants by 1975. It worked. American air quality improved dramatically. The phrase ‘clean air’ went from aspirational to mandatory. Clean Air Acts, Clean Water Acts, and the Endangered Species Act followed. A public health crisis in London created a model, and American democracy briefly agreed on the solution. See more at epa.gov.
The Great Smog of London in 1952 killed approximately 6,000 people in a week. The fog was so thick you couldn't see your hand in front of your face. The city essentially stopped functioning. By 1956, the British government passed the Clean Air Act—the first major environmental protection law in the world.
Eighteen years later, on December 31, 1970, President Nixon signed the American Clean Air Act with overwhelming bipartisan support—it passed the Senate unanimously and the House 374-1. The EPA was established to enforce it. The law required a 90% reduction in major air pollutants by 1975. It worked. American air quality improved dramatically. The phrase ‘clean air’ went from aspirational to mandatory. Clean Air Acts, Clean Water Acts, and the Endangered Species Act followed. A public health crisis in London created a model, and American democracy briefly agreed on the solution. See more at epa.gov.
Puzzle Appearances
The expression clean air has appeared in 1 puzzle:
- Puzzle #484 on September 28, 2026
Rate of Appearance in English Language Print
Google's Ngram project shows how often a pair of words has appeared in print every year since the 1800's.
Data from Google Books Ngram Viewer. Licensed under CC BY 3.0.
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