The recommendation from the Health and Safety Executive, which will order the removal of all Mark I stock by 2007, will be handed to the Government next week. If will then be laid before Parliament and, if no MP objects, become law.
The executive said the modifications would cost pounds 10,000 per carriage, a total of pounds 200m. Replacement would be more expensive.
However, train companies will be given more time to introduce central locking on the stock, known as slam-door, where each can be opened from the inside, even when the train is moving. In the 12 months to March two people fell from moving trains.
The move came as the executive's annual report showed the number of people killed on the railways had almost doubled in the past year from 25 to 48. But significant train accidents fell from 105 to 89, the lowest yet. Vandalism accounted for 59 per cent of all accidents, compared with 51 per cent the previous year. Assaults on rail staff rose from 267 to 335, which the executive said could be attributed, in part, to "rail rage".
The main element of the proposed modification to the rolling stock is to add a device that prevents one train riding on top of the other in a collision by interlocking the trains together - known as "cup and cone".
The executive has done a test involving a train hitting a stationary carriage at 35mph - a replica of the circumstances at Clapham on 12 December 1998, 10 years ago tomorrow.
Frank Davies, chairman of the Health and Safety Commission, which advises the Government on policy, said: "This excellent crash test result should clear the way forward for the HSC to send a proposal for new regulations, which will deal with the future of Mark I rolling stock - and a train protection system - to ministers before Christmas."
Vic Coleman, the Chief Inspector of Railways, added: "The cup and cone device offers a relatively inexpensive alternative to rebodying or replacement and would greatly reduce the number and severity of casualties in the event of a head-on collision."Reuse content