Three separate disputes have flared in England and Scotland involving the RMT union.
Workers at three rail companies are to take industrial action in the coming weeks in separate disputes over issues including pay and pensions.
Union members at Hull Trains will ban rest day working and overtime from Monday and stage 24-hour walkouts on August 8, 15, 22 and 29.
The union said talks at the conciliation service over a dispute about pensions had broken down without progress.
RMT general secretary Mick Lynch said: “RMT remains fully committed to defending our members’ rights to a decent pension in retirement and will do everything in its power to protect our members’ final salary pension rights.”
Hull Trains said contingency plans are in place to run a near-normal service and keep disruption to a minimum.
Senior conductors and train managers on East Midlands Railway will be striking on Sundays in the coming weeks in a dispute over safety.
The union said the company has imposed new working arrangements on some trains it believes are unsafe.
Mr Lynch said: “East Midlands Railway has introduced new working arrangements for Class 360 trains without any formal agreement with RMT.
“RMT believes that the Class 360 method of working that the company has imposed is not safe and that a second safety-critical person, preferably a train manager, should be in each portion of the multi-unit trains.”
Will Rogers managing director of East Midlands Railway, said the strikes damage the company’s ability to support the East Midlands’ recovery from the Covid pandemic and attract people back to the railway.
“The terms on offer included a reduction in working days and hours with no change to salary, the introduction of a new and generously-paid apprentice scheme, a new mentor scheme with a 4% salary increase, and a number of other improvements,” he said.
“Our absolute priority is to provide safe and sustainable journeys for our customers. That includes encouraging passengers back to the railway so we can return to being a growing industry which provides jobs and transport.
“We are confident in our contingency arrangements to ensure our services continue to operate and help those customers who need to travel, to continue to do so.”
Meanwhile, RMT members at ScotRail will strike on Sunday in a long-running pay dispute, with further Sunday walkouts planned.
The company said there will be a limited number of services running on Sundays.
A statement said: “We appreciate the inconvenience this will have on your travel plans, and we are running every service possible to minimise disruption.”