School of Civil Engineering Highway Traffic and Safety Analyses Lecture 16: Road Safety Concepts Purdue University School of Civil Engineering West Lafayette

Road Safety and Its Measurement What is road safety? Road safety crosses multiple areas Stakeholders of highway safety Present issues Safety Management System Objective, perceived, and nominal safety Measures of safety

Road Safety When is a road considered safe? Basic facts about road safety

Hadden’s Matrix Road safety crosses multiple areas   Travelers Vehicle Road + Environment Pre-Crash Crash Post-Crash Attitudes Driver Skills Alcohol/Drug Use Vision Education Safety Belts Use Air Bags Side Impact Protection Traveler’s Age Traveler’s Health First Aid Training Safety Equipment Vehicle Design Vehicle Size Vehicle Weight Automatic Seatbelts Fuel System Integrity Road Design Weather Conditions Road Operation Road Maintenance Lighting Delineation Roadside Hazards Fixed Objects EMS Response Hospitals Availability of Med. Services Matrix developed by William Hadden, Insurance Institute for Highway Safety

Stakeholders of Road Safety Legislature (funding, safety law and regulations) Government (overseeing) Road administration (road safety management) Bureau of motor vehicles (safety through proper licensing) Police (crash data, enforcement) Public research agencies (knowledge enhancement) Auto industry (observance of safety regulations, competition) Highway industry (safe road construction) Freight industry (safe trucks operation) Railroad industry (safe railway construction and operation) Insurance industry (reduce crash costs) Emergency medical services (reduce crash consequences) Private consultants (research, analysis, service) Citizens coalitions (lobbying for safety improvements)

Organizations Involved in Road Safety United States Department of Transportation American Association of State Highway and Transportation Officials (AASHTO) National Association of Governors Highway Safety Representatives (NAGSHR) National Transportation Safety Board (NTSB) Mothers Against Drunk Driving (MADD) Insurance Institute for Highway Safety (IIHS) American Automobile Association (AAA) Traffic Safety Foundation American Association of Motor Vehicle Administrators (AAMVA) American Association of Retired Persons (AARP) National Safety Council (NSC) Bicycle Federation of America American Trucking Association (ATA) Transportation Research Board (TRB) American Road and Transportation Builders Association (ARTBA) Roadway Safety Federation (RSF) American Traffic Safety Services Association (ATSSA)

Safety Emphases Special Users - pedestrians and bicyclists Drivers - curbing aggressive driving, reducing impaired driving, keeping drivers alert, increasing driver safety awareness, seat belt usage, aging drivers Special Users - pedestrians and bicyclists Vehicles - motorcycle and commercial truck safety, vehicle safety enhancements (antilock brake systems) Highways - vehicle-train crashes, highway intersection design and operation, head-on and across-median crashes, and work zones Emergency Medical Services - increase survivability of crash victims Management - gathering and analyzing crash data

Safety Emphases Highways Management Reducing Vehicle-Train Crashes Keeping Vehicles on the Roadway Minimizing the Consequences of Leaving the Road Improving the Design and Operation of Highway Intersections Reducing Head-on and Across-median Crashes Designing Safer Work Zones Management Improving Information and Decision Support Systems Creating More Effective Processes and Safety Management Systems

Safety Management System 1991 ISTEA required SMS from state DOTs 1997 TEA-21 - Transportation Equity Act for the 21st Century doesn’t require SMS SMS developed by some states anyway Florida http://www.dot.state.fl.us/safety/SMS/SMS.htm North Carolina http://www.doh.dot.state.nc.us/preconstruct/traffic/safety/

Safety Management System Cycle Safety-related Decision Making Safety Projects Implementation Safety Data Acquisition and Management

Safety Management System Decision-making Process Identify highway hazard Determine causes Determine countermeasures Develop safety projects Select projects for implementation Evaluate projects effectiveness

Objective, perceived, and nominal safety Objective safety – measured with crashes Perceived safety – felt by motorists Nominal safety – measured with compliance to design and operational safety standards

Measures of Safety Expected crash frequencies (crash/year) Expected crash rates (crash/unit exposure) Example unit exposures http://www.nhtsa.dot.gov/people/ncsa (used by Fatality Analysis Reporting System) 100,000,000 vehicle-miles traveled (VMT) 100,000 registered vehicles 100,000 licensed drivers

Measures of Safety http://www.nhtsa.dot.gov/people/ncsa

Measures of Safety http://www.nhtsa.dot.gov/people/ncsa