Passengers are being put at risk from being dragged under trains because staff are not checking if people have become trapped in the doors, a new report said.

Drivers and platform workers at stations are not making sure passengers' clothing or bags are free from the automatic doors before leaving the platform, an investigation into rail accidents revealed.

The report by the Rail Accident Investigation Branch (RAIB) into accidents last year found staff who make safety checks before trains depart are relying too much on technology preventing objects becoming trapped in the doors.

Staff have become too complacent and assume trains cannot leave the station if anything is obstructing the doors, according to the report.

Investigators highlighted two incidents, one in which a dog was killed when its owner was trapped in a door and another that left a woman fighting for her life after being pulled along the platform and into a tunnel.

The first accident was at Notting Hill Gate tube station in west London in January 2018 and saw the 78-year-old woman fall under a train after becoming trapped in the doors.

As the train left the platform it got up to around 21mph before the emergency brakes were activated after a passenger on the train pulled the emergency cord.

She was dragged some 246ft along the track and nearly 50ft into the tunnel and left with multiple bone fractures and an injured right leg. The woman spent around a month in hospital and is said to have now recovered.

RAIB recommendations included improving door systems to detect small objects and advised better training so train operators do not lose concentration when leaving platforms.

In September of the same year, Rose Barry got her hand stuck in the train doors at Elstree and Borehamwood station and her pet dog, Jonty, was dragged to its death.

Borehamwood Times:

CCTV captured the moment Jonty became trapped between the door and the platform. Credit: PA

She put her bags and dog lead on the train as she began to board, but the doors started to close, leaving the animal and passenger on the platform.

The woman managed to pull herself free but the lead was still stuck and the dog was pulled along the ground when the train departed. The animal was found dead in a tunnel near the station.

A report into the accident found it happened because the train driver did not observe the passenger near the train, both before he decided to close the train doors and before he decided it was safe to depart from the station.

The way the door obstacle-detection system was designed meant a thin object, such as the dog's lead, could not be detected. As a result, the train was able to depart with the dog's lead trapped in the closed door, the report found. It was also found that the driver took a "very short time" for the final safety check and may have been down to a lack of concentration.

There was no defect detected in door management technology, the report found.

Head of safety at Govia Thameslink Railway, Mark Whitley, said last year: "This was a deeply upsetting incident and we are very sorry for the distress caused to the dog's owner.

"As well as informing the Rail Accident Investigation Branch when it happened, we launched our own investigation immediately and have already introduced new guidance to drivers about the optimum time needed before departing, in line with the Branch's recommendations."

An investigation by the RAIB into incidents on the rail network found many similar accidents involved a "mistaken assumption" by members of staff, including senior employees, that door control systems will always detect an object in the doors.

Investigators said in their report: "A recurrent theme in so many of our investigations is the mistaken assumption that door control systems will always detect the presence of an object.

"It is therefore disappointing that we continue to encounter train dispatchers [who can be drivers, guards or station staff] who believed that door safety systems would always prevent the train from moving if an object became trapped in the closed doors.

"Worryingly, this misconception is sometimes shared by more senior members of staff."

Simon French, chief inspector of rail accidents, said of today's report: "Since becoming operational in 2005, RAIB has published details of 447 investigations. These describe accidents and incidents of many different types, which have occurred across the whole spectrum of the railway and tramway industry, and throughout the UK.

"However, it is six categories of event, which together make up around 40 per cent of RAIB investigations, which are the focus of the first series of key learning documents. We believe the industry still needs to do more to fully address the factors we have highlighted."