Structure for supporting an information or surveillance device above a road

A structure for supporting at least one information or surveillance device above a road, the structure comprising:

• at least one post extending upwards from the ground to an elevated position,
• a single overhead beam which is supported by said post, the single overhead beam extending over a horizontal distance above the road,
• the at least one information or surveillance device being connected to said single overhead beam and being positioned above the road,
• a catwalk extending along the single overhead beam,
• wherein said catwalk comprises a guard rail assembly which is movable between:
• an operating position in which the guard rail assembly extends upwardly from a lower part of the catwalk and protects personnel from falling from the catwalk, wherein in the operating position the guard rail assembly extends to above the single overhead beam, wherein the portion of the guard rail assembly which extends to above the single overhead beam is visible for approaching traffic, and
• a retracted, non-operating position in which the guard rail assembly is concealed behind the single overhead beam when viewed from a direction of approaching traffic on the road;
• wherein the guard rail assembly comprises
• a left guide rail assembly part extending along one side of the catwalk and comprising a left handrail supported by left pivotable struts, and
• a right guide rail assembly part extending along an other side of the catwalk and comprising a right handrail supported by right pivotable struts.