The Development of Police Vehicle Lighting: The Light Bar
Watching the first season of Adam-12, a police television show set in Los Angeles in the late 1960s, can be surprising when one sees the police vehicles. There are no familiar flashing lights at all. Instead there are two red lights mounted on the roof that glow steadily, and the vehicle relies far more on the siren to make its presence known in emergency situations.
Go forward a decade to 1970s police shows and the iconic single round red "gumball" light, with its spinning mirror system, appears. By the time of the early 1980s Hill Street Blues, the modern light bar can be seen, with multiple flashing lights in blue and red, but still using mechanical rotating mirrors and traditional incandescent lights.
This style of police car emergency lighting has been the standard ever since, continually refined with types of lights and choices of flash patterns.
In the last decade, the strobe light bar has become the option of choice for most agencies. Strobe lighting presents many advantages over the older systems. The vividly bright flashing lights offer increased visibility in both day and night situations. This increases officer safety on the highways by encouraging vehicles to move further to the left away from the lane next to the stopped police car, and increases civilian safety in emergency driving situations as modern car design with its soundproofing and stereo systems often mean that drivers see the emergency lights before hearing sirens.
The modern police light bar is also very versatile in its functions. In addition to the traditional flashing warning lights for emergency driving and roadside visibility, most offer options such as directional flash patterns, high intensity "takedown" lights to light up a vehicle stopped in front of the police car, white "alley lights" on each end of the bar for lighting areas on the sides of the vehicle, and lower intensity "cruise" lights that glow steadily and signal the presence of a vehicle parked on a quiet residential street at night, when the array of flashing lights could wake everyone on the street.
Further lighting options supplement the bar by adding flashing lights inside the vehicle by the front and rear windshields, and inside headlights and taillights.
In addition to increased visibility and lighting options, modern police strobe lighting can be placed in a lower, thinner bar arrangement, decreasing vehicle drag in emergency driving. The strobe lights also draw much less power from the vehicle, a particular advantage when a vehicle has to be parked with emergency lights on for a long period of time warning of a closed street or other obstruction.
Emergency vehicle lighting has come a long way from the days of Adam-12, and police officers and civilian drivers alike have benefited from the increased safety that modern police car lighting provides.
