Many driving instructors stress the importance of "defensive driving," meaning that drivers should be alert and prepared for any emergency. On the other side of the driving spectrum, however, lies a dubious practice known as driving by braille. Driving by braille involves an impaired, night-blinded or overtired driver using rumble strips and reflector bumps to stay in a lane. The term "driving by braille" was most likely inspired by the practice of driving over Botts' dots, cat's eyes or other reflector bumps in an effort to find the proper lane.
In a perfect world, all drivers would be perfectly sober, well-rested and competent enough to drive a motor vehicle. Unfortunately, the highway road system must also accommodate drivers who are operating at less than their best. Special grooves called rumble strips, for example, are carved into the shoulders of many highways and road. These rumble strips create an audible sound whenever a car's tires pass over them at highway speed. For a tired or impaired person driving by braille, the sound and feel of rumble strips beneath the tires can be a life-saving warning to pull back into a proper lane.
The other part of the driving by braille equation are the embedded reflector bumps in the road itself. These reflectors may go by different names in different regions, but they will produce a very noticeable sound and vibration should a driver begin driving by braille. These reflectors were originally designed to augment painted stripes on highways, but they have found a second use as reminders for impaired or sleepy drivers to move back into their lane. By running between the rumble strips and reflector bumps, a less-than-stellar driver could conceivably make it to their destination intact and ticket-free.
Drivers in California may be quite familiar with embedded reflector bumps known as Botts' dots. These raised ceramic, rubber or plastic reflectors were originally designed to replace or enhance painted traffic stripes, which often became virtually invisible under snow or after years of constant traffic. Originally, Botts' dots were attached to the road surface with steel spikes, but these soon proved to be very problematic if the reflector became damaged. Anyone driving by braille during those years may have received serious tire damage if they ran over an exposed spike. Modern Botts' dots use a special epoxy to keep them attached to the surface.
Rumble strips can also alert drivers to upcoming stops or reduction in speed. Reflector bumps can also tell drivers more about the rules of the road. White reflectors mean the adjacent traffic lane is moving in the same direction. A yellow reflector means the traffic in the adjacent lane is moving in the opposite direction. A series of blue reflectors indicates a nearby fire hydrant, while red reflectors indicate a car is traveling in the wrong direction. These color codes may prove very useful for drivers who feel the questionable urge to go driving by braille.