June 27, 1957
Everybody knows that Los Angeles suffered terrible smog in the 1950s, but without statistics, all we have are stories and photos of toxic clouds obscuring the landscape.
In fact, for the unfortunate people living in Los Angeles in 1957, what was deemed a Stage 1 alert (0.5 parts per million of ozone) would be a Stage 3 alert today. (In a Stage 2 or Stage 3 alert today, all non-emergency driving is discouraged and schoolchildren are banned from outdoor activities).
Now for the really ghastly facts: In 1957, a Stage 2 alert was 1 ppm and a Stage 3 alert was 1.5 ppm. The Mirror notes that no Stage 2 or 3 alerts had ever been issued, but that in a Stage 3 alert, the governor was authorized to declare a state of emergency.
One of the most polluted days in Los Angeles history was Sept. 13, 1955, when the city reached 0.9 ppm of ozone in Vernon and 0.85
Dr. Clarence Mills of the University of Cincinnati said: “The Los Angeles situation is so severe and so fraught with health dangers that any pollution control program should be put on compulsory basis.” Mills urged that a Stage 1 alert be issued at 0.2 ppm, which is, in fact, the current level. Using that figure, Los Angeles had four Stage 1 alerts in the first six months of 1957.
When someone told Mills that his lower figure would have Los Angeles County at a Stage 1 alert for most of the year, he replied: “That’s the way it should be.”
The California Air Resources Board link is here.