A young London innovator has launched a free smartphone app to help passengers avoid the most polluted and noisiest parts of the Tube.
Tanya Beri, 30, founded the CAIR London app in response to concerns about the impact of “Tube dust” on health.
She has expanded it to include the noisiest sections of the Underground, where the screeching and clattering of train wheels renders conversation impossible – and can trigger distress in neurodivergent travellers.
Ms Beri, from Harrow, came up with the idea of the app four years ago.
“With lung health being at the forefront of everyone’s mind during Covid, I started thinking about air pollution. Being a born and bred Londoner, the Tube sprung to mind,” she said.
“I think initially I was quite surprised how polluted it was and how many people this impacts.”
Last month a study commissioned by Transport for London found the Northern line had the highest levels of dust in driver’s cabs.
But the concentrations recorded across eight lines studied “were all below half the limit for dust of any composition to be considered hazardous to health”.
A different study, by Queen Mary University of London, published in 2022, found exposure to PM particulates increased the risk of infections such as pneumonia.
Commuters were advised to switch from deep-level to sub-surface lines or the Elizabeth line, which has advanced air ventilation systems.
Ms Beri, who won an Innovate UK young innovators award last year, visited all 272 stations to gather her own data and to help plot the “cleanest” routes.
The app uses data from a 2019 King’s College London study on Tube air quality. This found that concentrations of PM2.5 particles, which can be harmful to health, were about 15 times greater than above ground.
“The default setting on the app is not about giving the quickest route to your destination,” she said. “It’s about minimising the exposure to PM2.5s. Sound pollution is a filter we have added.”
She added: “In theory, you could make educated assumptions that the Tube lines above ground are going to be better for you.”
She found Stockwell station, on the Victoria and Northern lines, to have a particularly high level of pollution.
“I think how old the train is has a lot to do with it. If you have a deeper station, and an older train going through it for a long period of time, it is going to have accumulated more air pollution.”
She spoke with other passengers, including a woman with asthma who found it hard to breathe on the Central line.
People with neurodiversity issues told her how high levels of noise on parts of the Tube could leave them “overstimulated”.
One known trouble-spot is on the Jubilee line between St John’s Wood and Baker Street, where she has recorded noise in excess of 90 decibels. TfL aims to keep average noise levels below 80 decibels.
“It started as an air quality app but I’m now looking at highlighting quieter routes,” she said. “If there are people who find the noise particularly distressing or overstimulating, we can map out routes that can avoid the loudest screeches.
“From the sound pollution perspective, neurodivergence is something a lot of people have. Being triggered by loud noises can be difficult for them.”
The app can also show toilets on route.
Further updates to the app will add locations where passengers can fill up water bottles, and step counts to assist Londoners seeking to hit daily targets.
