Half a century ago, US government officials were concerned enough about the safety of rural highways to take a closer look at the causes of accidents. In an exhaustive survey, the Commerce Department’s Bureau of Public Roads — which has since become the Transportation Department’s Federal Highway Administration — concluded that excessively slow driving is every bit as dangerous as overly fast driving.
The agency’s chief researcher, David Solomon, compiled the results of a massive eleven-state study that covered 600 miles of main rural highways, accidents involving 10,000 drivers and interviews with 290,000 motorists. The road segments had traffic of up to 24,000 vehicles per day and speed limits of between 55 and 70 MPH. After crunching the numbers, Solomon found that the simplistic slogan “slow down” was not the key to improving highway safety, and that such slogans are actually counterproductive.