Abstract: Road fatalities are common and regular problem nowadays. These complex events associated with a variety of factors, like highway geometry, weather conditions, speed limits driver behavior, and human factors. Various highway geometric design consistency measures are alignment indices, driver workload, operating speed and vehicle stability. The safety assessment of highways has an important role in transportation engineering as the increased rate of accidents can be avoided by the consistent design of highway alignment .This paper  is focusing on the influence of alignment indices in the accidents rate. This work put forward a methodology for evaluating two-lane rural highway consistency and safety through alignment index. The influence of this alignment index on accidents is quantified through mathematical models and certain criteria were developed to evaluate the level of safety. The results of this work may greatly influence the implementation of road safety measures and thereby safety on highways.

Keywords: Operating speed, Vehicle stability, Driver Workload, Alignment Indices