The city was engulfed in a dense fog, reducing visibility to under a meter. Known as a pea-souper, this wasn’t an unusual occurrence in London’s winters. However, the severity of this particular fog led to a death toll between 4,000 and 12,000, surpassing even the peak daily mortality rates of the Covid pandemic in the UK. This tragic event sparked a significant transformation in air quality management, a lesson that is now crucial for cities like Delhi, grappling with similar challenges.
In the aftermath of the 1952 crisis, the UK government passed the groundbreaking Clean Air Act in 1956. The act first banned high-sulphur coal, a major contributor to air toxicity. Gradually, coal heating was replaced by gas, and polluting power plants and factories in the city were either upgraded to meet new standards or relocated. This shift was bolstered by the availability of North Sea gas, eventually leading to coal being almost entirely replaced.
The 1980s saw further advancements with the introduction of sulphur scrubbing and unleaded petrol, followed by the 1990s’ clean diesel programme to reduce particulate matter. The adoption of Euro emission standards, beginning in the 1990s and culminating in the ultra-stringent Euro VI standards, significantly lowered emissions.
More recently, London has implemented clean air zones, focusing on speed restrictions, prohibiting idling vehicles, and concentrating on sensitive areas like schools and hospitals. The city also introduced Low Emission Zones in 2009, limiting polluting heavy vehicles, and an Ultra-Low Emission Zone in central London since 2019.
These measures, coupled with substantial investment in public transport, have reduced vehicle presence on the roads, indirectly benefiting air quality. While London’s air quality is not yet up to WHO standards, it has improved significantly, with the worst days now better than Delhi’s best.
The medical evidence against air pollution is overwhelming. Studies have linked it to a range of health issues, including pulmonary disorders, heart diseases, strokes, autoimmune and neurological disorders. These findings have led to substantial policy changes, such as reversing the promotion of diesel vehicles.
In contrast, India’s situation, particularly in the Gangetic plains, is dire. An estimated 1.6 million people die annually due to air pollution, a figure triple the official Covid toll. Despite the urgency, the response has been lackluster. India’s unique challenges include road dust, which accounts for half of the particulate matter, and the transportation of pollutants across the Gangetic plains.
Delhi’s efforts, such as restricting BS III vehicles, mirror London’s actions but are just the beginning. Collective action is essential, given the transported nature of pollutants in the region. The ongoing political squabbles between states and the central government need to give way to cooperative solutions.
Ultimately, a robust public transport system seems to be a critical component of the solution. Delhi’s Graded Response Action Plan, while effective in short-term emergency management, does little for long-term air quality improvements. The staggering annual death toll due to air pollution should be a wake-up call for sustained, comprehensive action.
As history shows, only continuous and concerted efforts, like those post-London’s pea-souper, can lead to lasting improvements in air quality. Delhi and other Indian cities must learn from London’s experience and act swiftly and decisively to prevent a public health catastrophe.