New Delhi, Jan 3 (IANS): As a road safety measure, the Ministry of Road Transport and Highways has written to concerned authorities to install crash barriers by replacing old railings at bridges.

The initiative will prevent vehicles from rolling over and falling over the other side of the bridge in case of crashes on bridges.

"In all existing bridges retained without widening and having no crash barrier, existing railing shall be replaced by RCC crash barrier, except in situation where the deck slab is incapable of taking the additional load of RCC Crash barrier including the impact load due to collision of vehicle, in which case the metallic crash barrier with double W-Beam shall be provided," said the Ministry in a communication to different agencies.

The letter written by the ministry on January 2 has been addressed to chief secretaries of states and UTs and other concerned agencies.

"Before deciding whether RCC Crash barrier can be provided on an existing bridge in replacement of railing, a detailed study shall be done which should invariably include history of the structure, its performance in the past, its design and structural adequacy to take additional loads due to proposed modification, availability of the space to accommodate proposed changes and expected improvement in performance in terms of safety," said the Ministry.

It is seen that in case of existing bridges retained without widening, existing railing is usually not replaced by crash barrier.

The provision of a crash barrier is essentially required for safety of vehicular traffic but there are apprehensions about structural suitability of replacing railing of existing bridges by crash barrier, said the Ministry.