Clearing The Air On The Piccadilly Line

LONDON, UK—The Underground is a world-renowned web of tunnels and tracks beneath the busy streets of London. However, the toe-to-toe foot traffic, up to eighteen meters below ground, exacerbates the poor air quality issues plaguing the popular Piccadilly Line.

Coming from NYC, I was pleasantly surprised to ride a subway without rats scurrying along the tracks and random whiffs of urine. Imagine my disappointment, though, when I saw an Instagram story claiming that twenty minutes of exposure to the Piccadilly Line air quality is equally harmful as smoking a cigarette.

A frantic Google search assured me that while this claim was misinterpreted, the air quality is still 7x above the World Health Organization's recommended safe limit of PM2.5. With commuters inhaling up to 81% of the PM2.5, the link to increased rates of chronic bronchitis and mortality from lung cancer and heart disease becomes that much more real.

If the current system harms the health of up to five million passengers daily, what mitigative measures are the underground operators taking?

Transport for London's (TfL) public statements acknowledge the problem and redirect attention to the Elizabeth Line. The new line incorporates improved ventilation systems and screens separating the arriving train from those waiting to board. While the Elizabeth line is a step in the right direction, it is only one of eleven. The TfL fails to account for the 400 kilometers of other lines that do not meet the same standards.

To avoid intrusive remodeling, the TfL implements strategies that minimize air quality risks while preserving ridership. Their current approach attempts to use a combination of adding magnetic filters into the existing ventilation systems, intensive cleaning of the rails and tunnel walls, and screen doors between platforms and trains. As the TfL scrambles to balance these short-term relief efforts and new infrastructure investments, Londoners are forced to get creative.

Tanya Beri is an ex-underground commuter who used to experience recurring cases of tonsillitis while riding the tube. While recovering from a tonsillectomy, Tanya decided to create the app Cair.

Cair educates Londoners about the air quality risks of their desired routes and offers safer alternatives. To exemplify the impact of Cair, Tanya refers to how her route could have decreased the particles per cubic meter from 220 to 50. Ignorance is bliss until you start to notice the nasty post-underground cough.

The Undergrounds’s air quality issues require a collective response, with TfL taking the lead. By remaining informed, advocating for change, and supporting efforts to prioritize public health, we can all help create an underground system that connects destinations without risking the health of its riders.

The Piccadilly Train in action and a .5 selfie of a few of your SAIL writers.