London’s Great Smog of December 1952 was the largest in a series of “pea soupers” which brought normal activity to a halt across the capital. The smog lasted from December 5 to December 9 and led to a large spike in hospital admissions and as many as 12,000 deaths.
Pollution episodes like this one were driven by smoke from burning coal in city centres to generate power and heat homes (as recently as the 1980s power plants were still found right in the centre of London). This was then exacerbated by cold and windless winter weather: smoke + fog = smog. This was a very visible challenge. The ensuing Clean Air Acts focused on removing these key pollutant sources to make the air cleaner.
