Air conditioning – a condensed history
The first air conditioning systems were in use as early as 1902, but they were not for the comfort of people! According to Tim Hartford of the BBC World Service [1] , Sackett & Wilhelms Lithographing and Printing Company in New York found that varying humidity levels affected the quality of their printing. The paper had to be printed up to four times in four colours and changing humidity made the paper expand or contract slightly, misaligning the print. The company approached a heating company, Buffalo Forge, to devise a system to control the humidity. Engineer Wills Carrier invented the first modern type of air conditioning in which air circulated over coils chilled by compressed ammonia which kept the humidity at a constant 55%. Carrier’s invention soon proved popular in industries where excessive humidity was a problem – such as flour mills and the Gillette Corporation, where excessive moisture would cause the razor blades to rust. The benefi...