Abstract
An analytic study of highway fog was undertaken to determine fog densities that produce significant detrimental effects on highway safety and traffic operations. The study also evaluated the feasibility of a number of active and passive warning and guidance systems A survey was made of available fog measuring instrumentation. Some of the more advanced active guidance systems appear to be technically feasible at the present time. In the longer term, passing aids and automatic guidance systems currently being studied may prove to be readily adaptable to guidance systems for highway fog.