What Are the Causes of Fatal Car Crashes?

Tens of thousands of people die in car accidents each year. In 2008, over 34,000 fatal car crashes resulted in more than 37,000 people perishing. Drivers made up the majority with over 19,000 dead. Other people killed included the passengers, motorcycle operators, cyclists and pedestrians. The National Highway Traffic Safety Administration (NHTSA) noted that in every age group, males died more often in fatal car crashes than females whereas more females generally were injured. These statistics do not take into account the millions of people injured as a result of car accidents or the lives devastated by each car accident.

Alcohol Use

• Alcohol impairs a driver's judgment and reaction time.

  Drivers who died as a result of driving while intoxicated had average blood alcohol contents (BAC) of 0.16, according to professor David Hanson of the sociology department at the State University of New York at Potsdam. Those with the highest BACs were males ages of 25 to 35. Despite these sobering statistics, fatal car accidents because of drunk drivers decreased steadily from 1982 to 2005. The percentage of traffic fatalities in the United States because of alcohol use also decreased from a high of 60 percent in 1982 to a low of 39 percent in 2005.

Bad Weather

• Rain causes slick roads and low visibility for drivers.

  Some drivers tend not to acknowledge weather conditions when driving. Common sense dictates that as weather conditions deteriorate, you should slow your speed and keep a greater cushion between you and other cars on the road. Based on NHTSA statistics, a majority of weather-related car accidents each year occurs on wet roads. Statistics cited by the U.S. Department of Transportation Road Weather Management Program state that during the 11 years from 1995 to 2005, an average of 17 percent of crash fatalities occurred due to unfavorable weather conditions; this translates to an average of 7,400 people killed each year. Based on numbers for 2008 reported by the NHTSA, 2,442 fatal car crashes resulted from rainy conditions, and 838 fatal crashes occurred with snow or sleet.

Distractions

• Cell phones can become distractions for drivers.

  Distractions to driving include driver fatigue, eating and drinking, talking to passengers, cell phone use, texting and manipulation of objects while driving. Such distractions may result in car accidents by causing the driver to drift into another lane, drive off the road or even completely lose control of the vehicle. The NHTSA reported that an estimated 5,870 people lost their lives because of distracted drivers. This number equates to about 16 percent of all fatal car accidents. A good proportion of these cases occurred with drivers younger than 20.

Marijuana Use

• Marijuana use can impair cognitive functions.

  A 2005 study by French researchers Bernard Laumon and colleagues suggests driving while under the influence of marijuana, or cannabis, contributes to fatal car crashes. Researchers compiled data given by French police after administering blood and urine tests confirming the presence of marijuana in the systems of 10,748 drivers involved in fatal car accidents. The study found that driver usage of cannabis resulted in 2.5 percent of the fatalities.

Seizures

• A seizure occurs when the normal electrical activity of the brain becomes disrupted. The victim loses control of bodily functions and may not know what is happening. Laws exist that temporarily keep those suffering seizures from operating vehicles, but only during a restriction period between three and 12 months. Researchers from Johns Hopkins University studied death certificates to figure out how many cases of fatal car crashes from the years of 1995 to 1997 occurred because the driver experienced a seizure. The researchers found that 0.2 percent, or 86 of more than 44,000 fatal car crashes, was seizure related.

Speeding

• Laws are in place throughout the United States to enforce speed limits.

  Researchers from the University of Adelaide, according to data collected from casualty-causing car crashes, estimate that for every 5 kilometer-per-hour (3.1-mph) increase over a speed of 60 km/hr (37.3 mph), the risk of a crash involving a casualty doubles. Many drivers fail to realize that reaction time -- the time needed to react to a hazard after seeing it -- increases as they increase the speed of their vehicles. As a result, when increasing speed, drivers need more time to effectively apply the brakes.

SUV Rollovers

• SUVs have high incidences of rollovers.

  In 2002, sports utility vehicles, or SUVs, constituted an estimated one-quarter of cars sold in America. Of these vehicles, approximately 70,000 would experience the rollover effect, resulting in about 2,000 fatalities. Because of instability resulting from their height-to-width ratios, SUVs have a tendency to roll over, even at speeds of 20 mph. These alarming facts inadvertently emerged when Congress conducted hearings in 2000 regarding fatalities caused by rollovers on vehicles equipped with Firestone tires. Data taken from the same period showed that more than 12,000 people died as a result of rollovers not related to the condition of the tires as compared to the 300 who died directly from flawed tires.