Specifications include, but are not limited to: • Develop methods to determine the friction requirements for different conditions (identified in Phase I below). • Develop procedures for WSDOT to monitor pavement friction levels and implement thresholds for investigation. • Determine recommendations for optimal management of pavement friction • Phase 1: The research team will analyze pavement friction and safety performance using random parameter modeling. This modeling process controls for changes in context, geometrics, and other factors known to effect safety performance while reviewing the significance and effect size of possible contributions of friction to safety performance. The modeling will use at least the following data sources: WSDOT crash, roadway, and traffic volume data; pavement friction data and control for other factors known to influence safety performance. Safety performance will be expressed by crash type and severity for the analysis, and leverage lessons learned during the WSDOT funded SPF research project.