The government had received, and ignored, a grim warning of what could happen in a killer fog. In 1948, in the small American industrial town of Donora, Pennsylvania, a similar 'inversion effect' had devastated the landscape and caused many deaths.

In 1950, an international conference met to study the Donora disaster and recommended the rapid establishment of 'smokeless zones' in conurbations. But the British government ignored the urgings of its own delegates to the conference. It was racing to boost its exports of high-quality coal while at the same time flooding the domestic market with inferior fossil fuel. The result, in December 1952, was a man-made environmental catastrophe, one of Britain's worst peace-time disasters.

The subsequent outcry produced the Clean Air Act of 1956, which, by controlling domestic smoke output for the first time, banished the 'pea-souper' fogs that had become synonymous with London. In the process, the Act transformed the demography of the city, turning previously run-down areas such as Camden and Cannonbury into the gentrified preserves of middle-class professionals who had been persuaded to move back into the city from the suburbs. 

But there is no room for complacency. Motor vehicles are now an infinitely greater source of atmospheric pollution than they were in 1952. The continued poor quality of the air in the London of the 1990s holds out the prospect of more major public health problems.

Next: RESOURCES

Battersea Power Station was a major contributor to air pollution
 
 

The Clean Air Act was the Government's reaction to public distress