I recently had discussions with the manager of a small office complex about improving the security of a rear parking lot walkway. The area in question was a flight of concrete stairs that lead down to a customer and employee parking lot. While no serious crimes had been reported, employees leaving the building during evening hours reported reaching the bottom of the stairs and sometimes suddenly coming face to face with transients, panhandlers, and individuals that just didn’t belong there. Because of the physical configuration of the walkway and an easement, fencing the walkway was not an option. The management posted NO TRESPASSING signs which were largely ignored and the area was already illuminated with traditional flood lights. When I suggested removing the traditional vapor flood lights and illuminating the area instead with bright BLUE flood lights as a way to create an enhanced sense of security and to discourage insalubrious people from using the walkway, the manager looked at me like I was speaking Greek!
Blue security lights. Really?
Well . . . YES! There is some emerging evidence that blue security lighting – not to be confused with “blue light” surveillance cameras, may deter crime and can enhance the sense of safety and security when used appropriately. In recent years authorities in Japan, England, and Scotland have experimented with using blue light illumination in public places and have reported reduced crime and reduced fear of crime in areas illuminated by a “blue fog.”
Why does blue light illumination apparently cause a decrease in crime and create a feeling of safety and security? No one really knows for sure but some have suggested that because blue light is the universal color of law enforcement lights there is a strong association between the color blue and authority. It has been speculated that blue lights arouse thoughts of authority and this causes would be criminals or unsavory individuals to avoid the area. There is also some psychological evidence that demonstrates the color blue has an overall calming effect on people.
While all of these explanations may have some validity, there is no question that blue security lighting just plain looks different. Everyone is accustomed to seeing an area or premise lit up with traditional security flood lights. In fact it is so common that most people don’t even consciously notice it. But, an area lit up with blue light causes people to take a second look. These “extra eyes” peering at a location makes crooks and people who don’t belong in the illuminated area feel uneasy. Consequently, they are inclined to avoid the area under blue light illumination. At least that’s my explanation why blue light illumination worked well for the office complex walkway.
My experience and the results reported from Japan, England, and Scotland all indicate that blue illumination security lighting has a place to play in crime prevention and can help create a sense of security. But using lighting to prevent or deter crime or to enhance a sense of security of a particular area or building, whether it is blue light or the more traditional white light, is not as simple as just shining some light over an area. When considering illumination, security professionals should be mindful of integrating the lighting into an overall security program. They should also be familiar with IESNA (Illuminating Engineering Society of North America) guidelines and understand CPTED (crime prevention through environmental design) principles as well as have a working knowledge of security lighting factors like horizontal luminance, luminous flux density, spectral power distribution, visual adaptation, and disability glare.