At long last, and a little late, the summer has arrived, bringing a short sharp heatwave across the UK. While many of us might be thrilled about a final bit of sun for what has been a decidedly drab 2023, heatwaves can be horribly uncomfortable for many and life threatening for some. And that’s in the open air. Imagine having to put up with them for eight hour stretches deep beneath the ground? This is a situation with which drivers on London Underground are thoroughly familiar.

Data from Transport for London (TfL) showed the average temperatures for the tube lines in July 2020 were close to 30°C on the Bakerloo and Central lines. One driver described  the conditions as being “like an absolute steam room in the driving cab during the summer”.

There is currently no UK law that specifies maximum safe working temperatures. Indeed, according to train drivers’ union ASLEF, even the laws that do cover workplace temperature don’t apply to train drivers’ cabs.

When it surveyed drivers on their working conditions, ASLEF discovered that a whopping 85% reported struggling with extreme heat in the cab, particularly during the summer months.

Asked how frequently heat was a problem, 43% said every day or almost every day, 29% said three to five times a week, 15% twice a week, and 12% once a week. So, 72% of respondents experienced cabs that were too hot for much of their working time during the periods they identified as problematic.

One tube driver said: “Temperature often exceeds 40°C and, on many shifts, I’m left feeling physically sick due to the heat.” Another pointed out: “When you spend most of the shift thinking how to keep cool, your mind isn’t on the job at hand.”

An ASLEF spokesperson added: “When it is hot, drivers are sometimes forced to open windows (which makes it very noisy); are extremely uncomfortable or sweating, and often unable to access enough water to stay hydrated.

“We know that a comfortable driver is a safe driver, and we all want the railway to be focused on safety as a top priority… It’s time to protect all workers, and for all of our cab conditions to be improved.”

The TUC, which represents 5.5 million workers in 48 member unions, has also called on the government to bring in more effective laws regarding workplace temperature, with a legal maximum and no exemptions, and has called upon employers to ensure that their workers’ settings are a safe and maintained at a reasonable temperature.

In the sauna-like conditions brought about by heatwaves, it is imperative that tube drivers – and, of course, their passengers – have access to an effective form of climate control.

A major trial on London’s Underground system is evaluating the viability of reducing temperatures on the deep tube network (see box). TfL is testing a new cooling system designed to reduce temperatures for tube passengers on hot days.

If the trial is successful and funding is secured, it will be extended to five deep stations on the Piccadilly line – Green Park, Holborn, Knightsbridge, Leicester Square, and Piccadilly Circus. Longer term, it could be rolled out across the Bakerloo, Central, Jubilee, Northern, Piccadilly, Victoria, and Waterloo & City lines.

London Underground is one of LH-plc’s largest customers with the company servicing and repairing the air conditioning inside the trains, mainly the drivers’ cabs. LH-plc’s cutting-edge railway air conditioning refurbishment and servicing centre in Wimbledon, south-west London combines state-of-the-art facilities with well-qualified and experienced engineers to offer an exceptional service that is both reliable and offers premier quality.

We carry out work on behalf of many of the major UK rail carriers as well as the London Underground tube operators, employing a highly skilled team of engineers boasting more than 30 years’ experience in this specialist sector.

Find out more about our Railway Air Conditioning Services.