Long-term work to improve temperatures bus drivers face in hot weather.


A Stagecoach bus in London. ©Lukasz Pajor/Shutterstock

Reporter's concern

  • For years, drivers had been experiencing uncomfortable and unsafe temperatures in buses out of Plumstead garage. This had got worse.
  • The reporter didn’t believe Stagecoach checked if most buses’ air-cooling systems were ready for hot weather in the run-up to summer. 
  • Only a few buses had an adequately working air-cooling system. Often the systems blew hot air.
  • These conditions could cause fatigue or heat exhaustion, impairing drivers’ concentration or making them faint at the wheel.

They wanted Stagecoach Bus London to review the fleet to identify buses needing air-cooling systems to be topped up – and to ensure that there is an effective way to identify buses that need this before summer.

Stagecoach Bus London's response

  • We thank the reporter and colleagues for their perseverance during the extreme weather. 
  • All London bus operators must meet Transport for London (TfL) bus specifications, which dictate what is fitted. 
  • The air-cooling systems work on the same principles as an air-conditioning system but are not the same as in a personal car. When the driver activates the system, it is designed to reduce the cab temperature by up to 10 degrees, which in a normal summer is usually enough. At Plumstead, we have also fitted buses with a fan in the cab to improve air circulation.
  • Our records show that since January 2022, 120 of the buses at Plumstead have had their air-cooling system serviced, which is most of them.
  • Engineers check the air-cooling system is working on each bus’ 28-day service inspection and record this in the service log.
  • Drivers complete a condition report each time they take over a bus and should report defects (but we understand if they do not check the cooling system in cooler periods).
  • Our contractor attends within 48 hours to repair defective systems once they have been reported. Each bus is scheduled for a yearly service with them so that the systems are proactively maintained in line with specifications. 
  • We had a spike in reported defects during the hot weather, but inspections found few were defects. The system could not draw down the temperature enough due to the extreme heat.
  • We are consulting with our contractor to find a way of identifying vehicles with defective or inefficient cooling systems before anticipated extreme heat events.
  • TfL is working on a climate adaptation for the new bus specification. This will involve the temperature dropping further and in less time. Contractor Graysons, an expert working across operators, is determining how to retrofit these improvements.

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