A rail firm has been fined £1m after a man died leaning out of a train window.
Simon Brown, 24, was killed when he hit his head on a steel gantry on the side of the track while on the Gatwick Express in London in August 2016.
In May, Govia Thameslink Railway admitted a health and safety breach because a sign saying not to lean out was not displayed clearly enough.
The rail regulator has written to firms demanding “immediate action” over trains with these types of windows.
Ian Prosser, the Office of Rail and Road’s director of safety and HM Chief Inspector of Railways, said it was to “GTR’s credit that they pleaded guilty”.
“There are still some trains with droplight windows operating on the network and we have written to operators instructing them to take immediate action to prevent a similar tragedy happening again,” he added.
The ORR said there were about 1,500 of the droplight windows in circulation on the rail network.
Simon Brown’s family said in a statement: “Irrespective of the penalty imposed, we hope, as a result of our tragedy, that operating companies up and down the country will take their responsibilities to the travelling public more seriously.”
The accident happened on 7 August 2016 at Wandsworth Common station as the Class 442 train was travelling to London Victoria from Gatwick Airport.
The train was travelling at 61mph when Mr Brown suffered the fatal injuries.
Mr Brown, from East Grinstead, West Sussex, had been previously described by friends as a life-long railway fanatic who was working in the rail industry.
He first volunteered on the Bluebell steam railway in Sussex aged nine and was working as an engineering technician with Hitachi Rail Europe in Bristol.
The regulator said the “droplight” windows were mostly confined to old InterCity trains and “charter” rolling stock, and in most cases there were four windows per carriage.
Rail firms using carriages with these windows have been asked to carry out a risk assessment of their use.
A report by the Rail Accident Investigation Branch said there had been a sticker on the door warning passengers not to lean out of the window, but it was “cluttered” with other signs.
The warning sticker was placed on the left alongside six other notices.
The RAIB has also made recommendations telling operators to “assess the risk arising from reduced clearance outside those windows”.
Along with the fine, the firm was ordered to pay £52,267 in costs.
Govia Thameslink said it had taken the health and safety failings very seriously and pleaded guilty at the earliest opportunity.
The firm’s chief executive Patrick Verwer said: “I am very sorry for the death of Mr Brown and the deep distress this tragic loss has caused his family and friends.”