On Thursday, 4 December 1952, London was plunged into semi-darkness as a dense smog of epic proportions blanketed the British capital. Over a four-day period the noxious smog stifled London, and although it appeared at the time to be a mere inconvenience, it would prove to have devastating consequences.
Londoners were not unused to the sight of thick smog over the capital. From the earliest days of the industrial revolution, the air quality in London had gained a poor reputation. Intermittently, when weather conditions allowed, the man-made smoke in the atmosphere would combine with naturally occurring fog, forming a thick yellowy haze that hung over London like a shroud. For its dense consistency and yellowish colour, the smog became known as a “”pea-souper.””
The weather in the days preceding the Great Smog had been unseasonably cold, leading to an increased amount of fuel being burnt in London homes. At this time, most British homes were heated by coal fire, with the majority of householders using coal that was of a poor quality, and high in sulphurous content. Normally this would not be such a problem, but a sudden onrush of high pressure sent a front of warm air over London, trapping the cooler smoke-filled air beneath it. The smoke-filled air had no means of escape, and London was soon enveloped.
The smog had an immediate impact on the city, radically reducing visibility and drastically restricting movement. At its worst, visibility was thought to be between one and five yards. It soon became apparent that traffic was unable to circulate safely, and after several hours the decision was made to suspend the London bus service. Even the ambulance service had to cease operation, leaving those with urgent medical needs to find their own way to hospital.
At the time of the smog, the consequences for London were not immediately apparent. There was no mass hysteria or panic, and the immediate health risks were not clear. However, in the days that followed the smog, it emerged that around 4000 people had died as a result of acute respiratory conditions, directly attributable to the record levels of carbon and sulphur dioxide in the air.
In the weeks following the smog, the true extent of its debilitating potential became clear. Hundreds upon hundreds of Londoners complained of respiratory illnesses, and the death rate rose sharply. Long after the fog had disappeared, smog related deaths were being recorded. In the end it was estimated that around 12,000 deaths were caused through smog pollution.
The seriousness of the episode led to changes in government policy towards pollution, and in 1956 the Clean Air Bill was passed in the British parliament. From then on, measures were brought in to encourage people to switch from using coal fires, and the use of smokeless fuel was promoted. Legislation was also brought forward that would see polluting power stations moved away from urban areas. Although change could not happen overnight, this ensured that after years of declining quality, London was gradually able to breathe more easily.
Credit: Getty Images
Caption: A London bus conductor walks ahead of his vehicle to guide it through the thick smog.