The Two Second Rule: What Every Community Should Know
An analysis of the 100-Car Naturalistic Driving Study, conducted by the National Highway Traffic Safety Administration, released in 2006, showed that taking one’s eyes off the road for more than two seconds for any reason not directly related to driving (such as checking the rearview mirror) “significantly increased individual near-crash/crash risk.”
What factors make drivers likely to look at an electronic sign for more than two seconds at a time, and therefore put themselves and others at risk?
- They are extremely bright and are designed to be visible in bright sunlight and at night. The eye is drawn to them far more strongly than to traditional illuminated billboards. They are designed to be eyecatching, and they are.
- They can be seen from great distances, even as far away as sixtenths of a mile, making them distracting even before they begin to communicate their messages.
- The images rotate every 6–10 seconds and drivers will naturally look at the sign long enough to see what comes up next. There may be as many as 10 messages in the rotation.
- The Florida Department of Transportation’s official position is that it takes a minimum of six seconds to comprehend the message on an electronic billboard, which is already three times the safe period for driver distraction.
- Because the messages change daily or even hourly, even commuters who pass by the signs every day will look to see what’s new. Traditional signs become visual background noise for local drivers, and thus have less safety impact; but electronic signs never blend into the background.
- Younger drivers may be more easily distracted by electronic media, and older drivers may require longer viewing times to comprehend often confusing, elaborate, and colorful images.
Are electronic signs especially attention-getting?
“Nothing’s as eye-catching as an electronic LED display.
The brightly-lit text and graphics can be seen from hundreds of
feet away, drawing the attention of everyone within view.”
Source: Voiceover narration of TransLux promotional video (www.impactmovie.com/translux)
Will people stare at a changing sign to see what’s next?
“The reason [electronic] advertising works is because it is
impactful. If you see people parked at the stoplight watching it,
you see their eyes waiting for it to change.”
Source: Clear Channel Outdoor Des Moines division president Tim Jameson, quoted in the Des Moines Business Record, Feb. 4, 2007
Additional Resources
The Impact of Driver Inattention on Near-Crash/ Crash Risk: An Analysis Using the 100-Car Naturalistic Driving Study Data
April 2006, National Highway Traffic Safety Administration, U.S. Department of Transportation
A major study of driver inattention, primarily involving distractions inside the car, but finding that any distraction of more than two seconds is a potential cause of crashes and near crashes.
Traffic Safety Evaluation of Video Advertising Signs
Transportation Research Record: Journal of the Transportation Research Board, No. 1937, 2005
A study of electronic signs in Toronto, which finds that “On the basis of the eye fixation study and the pubic survey data, it is apparent that video advertising can distract drivers inappropriately and lead to individual crashes,” but calls for additional research due to other conflicting data.
Research Review of Potential Safety Effects of Electronic Billboards on Driver Attention and Distraction
September 11, 2001, Federal Highway Administration, U.S. Department of Transportation
A summary of existing research (as of 2001), on the subject of the safety of electronic signs and a call for additional studies.
Milwaukee County Stadium Variable Message Sign Study: Impacts of an Advertising Variable Message Sign on Freeway Traffic
December 1994, Wisconsin Department of Transportation
Study of the dangers posed by an electronic sign in Milwaukee along I94, that concluded that “It is obvious that the variable message sign has had an effect on traffic, most notably in the increase of the side swipe crash rate.”