Roadside encroachment parameters for non-freeway facilities. Prepared for the 55th Annual Meeting of the Transportation Research Board, Washington, January 1976.

This research developed estimates of the necessary inputs to the roadside hazard model developed in NCHRP Report No. 148, (See B 6326) in order to make the model usable for predicting the effectiveness of roadside safety improvements on all classes of highways. This involved the collection of additional data for predicting roadside encroachment rates, and obstacle severity indices for all classes of highways other than freeways.