In 1969 the Cuyahoga River in Ohio caught fire. This would have been a big news story at the time, had it not been for the fact that the river had caught fire numerous times in the past, in fact 13 times since 1868. However, what was notable in 1969 was that this time the fire, on an oil slick, was near the city of Cleveland and subsequently influenced how quickly the country adopted the Clean Water Act in 1972.
In 1973, ASHRAE Standard 62 reduced required ventilation from 10 cubic feet per minute (4.7 L/s) per person to 5 cubic feet per minute (2.4 L/s) per person. This action was found to be a contributing factor to “sick-building syndrome,” with building regulations getting tightened and ventilation rates being decreased to save energy. The policy was well intended, but today we are still dealing with a legacy of under ventilation and other significant issues inside of buildings that impact their health.