@chdot: A requirement to fit Central Door Locking (CDL) to historic railway coaches could spell the end of the line for the Jacobite.
As was stated in the article, West Coast Rail and other heritage rail operators have known about this requirement for something like 20 years. Some other operators have deployed a technical solution (i.e. central door locking) but this is not straightforward on the Mark 1 coaches which WCRC runs on The Jacobite (the coaches are steam heated & vacuum braked, so there is currently no source of power throughout the train from which a centralised locking system could be operated).
WCRC have therefore been operating under a series of exemptions granted by the ORR which were dependent on WCRC having in place other mitigations - specifically, stewards manning the vestibules to operate the manual door locks, open and close the doors, and stop passengers from operating the locks or doors, or hanging out of the windows. A visit by the ORR earlier this year found that these procedures were not being followed, so they shut the service down until WCRC could convince them that they had taken action to ensure that the trains were fully manned and the staff were enforcing the rules about the use of the doors and windows.
The Jacobite's operator says it has robust safety procedures in place to protect passengers with one steward per carriage in place to operate doors and monitor droplight windows and an additional guard.
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"The system we have in place works and it is safe," says Mr Shuttleworth, who lives in Derbyshire.
Weasel words: the ORR found that the system was not "in place" and didn't "work" when they paid the service a visit. WCRC had to demonstrate that they were taking their safety system seriously and following it properly before they were allowed to start running The Jacobite again in August.
A number of other heritage operators run trains with coaches which lack CDL, under the same or similar exemptions as applied to The Jacobite. AFAIK none of them have been prohibited from running as a result of being found by the ORR not to be following their documented safety systems.
WCRC have significant form: a major Signal Passed At Danger (SPAD) incident in 2015 where a steam hauled railtour ran through a junction, for which WCRC was hit with a £260,000 fine. There have been numerous other incidents since. That might be one reason why the ORR have been keeping tabs on their safety system compliance.