Safety Flashcards
How many people killed on world’s roads each year?
More than 1 million
4 E’s of transportation safety
Engineering
Education
Enforcement
Emergency
Engineering
Make system safe and fast: separate lanes, signs, markings.
Education
Inform users of rules and rights and limitations. Prevention
Enforcement
Law enforcement prevents violations
Emergency
Minimize damages/outcome of event
6 steps of engineering portion of safety
Planning Design Construction Operations Maintenance Decomission
Half of all fatalities
Pedestrian, cyclists, motorcycles
2004
Traffic accidents # 8 cause of death
Main causes of road accidents (driver related)
Distracted driving!
Recognition error/decision error
Performance error
Vehicle related causes
Tires, wheels/breaks, steering suspension, transmission, engine
Environment related causes
Slick roads (ice) View obstructions Other
Type of vehicle with largest # of crashes
Passenger vehicle
Design considerations for safety
Lane width Grade Horiz curve Shoulder Median
Predictiability
Good to be consistent and logical
As lane width increases…
traffic accidents decrease
As vertical grade increases…
accident rates increase
***As horizontal radius decreases…
accidents inside curve increase
As shoulder width increases…
of accidents decrease
What type of medians are better for safety?
Those designed at a lower altitude than the pavement
What percentage of accidents involve human factors?
93%
Where are road most unsafe?
Where the road design prevents drivers from predicting situations ahead
Types of traffic signs
Regulatory
Warning
Guide
