Joules was also interested in the adverse effects of air pollution on health and, as vice-president of the SMA, established a special committee on 'Clean Air and Diseases of the Lung' in 1954, which included medical experts on industrial diseases, and representatives of the trade unions. This was highly topical since the Great Smog of December 1952 had only recently happened and was estimated to have caused at least four thousand avoidable deaths in London. In 1953 in a letter on Chronic Bronchitis to the "British Medical Journal" he wrote:‘The air we breathe is as important as the water we drink. It must be uninfected and unpolluted.’ He urged the government to take action to control air pollution. Sir Hugh Beaver, chairman of Guinness Brewers and a member of the management committee of the Central Middlesex Hospital, was appointed to lead a parliamentary inquiry into the problem. Pressure from Joules helped provide evidence for the Beaver Committee. The Clean Air Bill that resulted became law in 1956 and smog gradually diminished in London and other British cities.