Using a selected sample from annual published accident statistics, this paper presents an analysis which responds to the following questions: Is it better for a vehicle out of control to hit a guard rail ? or (a) a tree, wall or fixed obstacle at the roadside; (b) run off the carriageway in the absence of any obstacle or barrier, and end up in the sea, a ditch, or against an embankment ? The results of the analysis are overwhelmingly in favour of guard rails, which it is emphasised, are not intended to prevent the accident but to transform it from one type to another in which injuries, their severity and therefore deaths are reduced. Reference is made to OECD Report No. 22, 1972, which states that in the type of accident concerned safety fences reduce the severity by from 30 to 50%.
Abstract