Ten Hazardous Traffic Conditions

Street design, street conditions, weather and human factors can all affect traffic safety. Here is a list of categories of hazards that increase the risk of traffic accidents.

Roadway departure hazards:
Vehicles leaving the roadway with hazards ... intentional or non-intentional ... cause approximately 15,000 deaths per year. Roadway departure crashes occur on both straight and curved sections of roadway and often involve rollovers or collisions with fixed objects, such as trees and utility poles. Roadside hazards also include steep side slopes, drainage ditches along the roadway, and narrow shoulders not large enough to accommodate a vehicle that is disabled or is out of control.

Road surface conditions:
Defects in the road surface, such as pavement edge drop-offs, dips, buckling, potholes and reductions in surface friction due to age, wear, inadequate drainage during rain storms, and snow and ice impair vehicle stopping and maneuvering capabilities.

Narrow roadways and bridges:
Narrow roadways make it difficult for drivers to safely maneuver through a narrow path. Narrow bridges are particularly hazardous. Collisions with bridge ends are relatively infrequent, but they are often severe. Such crashes usually occur when the width of a bridge is less than that of the approaching traveling lanes and shoulders. As a result, vehicles strike the ends of bridges, guardrails, curbing, or vehicles traveling in the opposite direction.

Railroad crossings:
About every 100 minutes someone in America is hit by a train and people are 30 times more likely to die when involved in a collision with a train than with another car, bus, or truck? A 150-car freight train traveling at 50 mph takes over 1-1/2 miles to stop.

Work zones:
Work zones, defined as construction, maintenance, and utility areas, create conditions that can be hazardous to drivers and highway workers. About 700 people are killed and 37,000 are injured in work zones every year. Construction zones cause detours and changing traffic patterns, reduced speed limits, congestion, delayed travel times, heavy equipment obstructions, impaired visibility, debris hazards and human factor frustration. Some construction workers are poorly trained at directing traffic throught the construction zone, causing delays and increased hazards. Some work zones are poorly marked, and warning signs are hard to see, especially at night. Warning signs and traffic control devices may not be related to actual work in progress or may not accurately portray real work zone hazards (e.g., lane closure signs show the incorrect lane closing). Drivers thus disregard these warning signs with potentially tragic consequences.

Intersections:
Confusing turn lanes, blind spots, confusing pavement markings, or lack of appropriate or inadequate signage or traffic signals. Obstructions, including trees or bushes, can block a driver's view of signs, signals, and other traffic control devices.

Roadway design limitations:
Many local roads are outdated because they were built to hold fewer cars traveling at slower speeds. Because of the sharp increase in vehicle miles traveled over the past 30 years, many of these roads are now high-speed commuter corridors. Safety is compromised by hazards such as sharp curves, poor signs and markings, obstructing trees and shurbs, utility poles too close to the road, and lack of medians to separate oncoming traffic. Fatality rates on these roads can be five times as high as on the heavily traveled and high-speed Interstate system. Local governments, which are responsible for over 75% of our entire road network, prioritize their limited resources and fix the most serious problems first.

Roadway access problems:
Roadway access conditions, such as driveways, roadways into new developments/businesses, and blind entrances, can cause driver confusion and frustration. Safety depends on drivers that must remain alert to changing traffic patterns and respond with quick reactions.

Pedestrian and bicycle traffic:
Bicycle and pedestrian traffic must be accommodated and speeds must be controlled. There were 5,220 pedestrian deaths and 69,000 injuries during 1998, and these numbers are expected to increase as our population ages. By 2030, one in five Americans will be over age 65. Pedestrians over 70 constitute approximately 9% of the population, but they account for 17% of the fatalities. In 1998, 761 bicyclists were killed and an additional 53,000 were injured in traffic crashes.

Impaired Driving:
Weather and visibility problems, traffic congestion, alcohol, drugs, cell phone or text message distraction, other multi-tasking while driving, road rage, lack of experience, decreased perception due to aging or illness, fatigue and sleep deprivation are all factors that increase the chance of human error as a cause of accidents.