Would you rather fly, drive or take a train to Washington, DC from Chicago?
As of June 23, 2009, at least seven people were killed and more than 70 were injured in a commuter train collision that occurred during the afternoon rush hour in the nation's capital. It was reported by Brian Witte of the Associated Press that "it was the worst crash in the history of Metrorail, the pride of the District of Colombia tourism industry that has shuttled tourists and commuters around Washington and to Maryland and Virginia suburbs for more than three decades".
Risk perception is a phenomenon or rather a subjective judgment and assessment about the likelihood and severity of a risk occurring. And a risk can be any adverse event, such as getting attacked in a dark alley, getting sick from an undercooked hamburger or dying in a fatal plane crash. One's acceptance of a risk is often influenced by several factors. Some of these factors are whether or not the risks are natural or man-made, under one's control or others, immediate or delayed effects and fatal or not. So for example, a teenager may "accept" the risk of cancer (delayed risk) when they are 50 years old due to smoking cigarettes for over 30 years or an individual may "accept" the risk of living near an earthquake fault line in California (natural risk).
Understanding a particular risk, or rather knowing the actual probability that an adverse event will occur, such as 1 out of a million, is sometimes not enough to curtail the fear of this negative event occurring. For example, there are people who will not fly in an airplane because of their fear of flying, despite the fact that the National Transportation Safety Board (NTSB) reported this year that in 2005 "only 1 of every 14.9 million passengers who boarded a Part 121 [major airlines and cargo carriers] air carrier flight was injured in an accident". In contrast, 14.70 per 100,000 people were fatally injured in a vehicular accident in 2005, according to the National Highway Traffic Safety Administration (NHTSA). Consequently, motor vehicle traffic crashes were the leading cause of death for children and adults between the age 4 and 34 years.
The train accident that occurred on June 22, 2009 in Washington, DC was a rare event. Since 1982, three passengers and five Metro employees have been killed due to derailments or train operation accidents. Considering that the Metrorail carries an average of 727,684 passengers per day during the workweek, those odds seems to be pretty o.k.
Author's Note: This post is a guest blog from Dr. Jennifer Roberts, Senior Scientist at Exponent and an expert in public health.
Editor's Note: For more blogs from Dr. Rabiah, visit Science Chicago's website at: http://www.sciencechicagoblog.com