A Little Truth About “Security Lighting” and Human Nature.

Especially if you live in the country, you may have a “Security Light” like this one. Probably no one sold it to you. You just figured you had to have it, almost like a mailbox, right?

Maybe you were given a little encouragement when you authorized the monthly charge with an image such as this. We call him Dastardly Dan. Notice Dastardly Dan has a flashlight. The message is plain – your home is at risk of being burgled in the night – unless you have a “security light”.

A modest sum each month to keep this guy away is a bargain, right? But, have you ever asked yourself exactly how lighting some part of your yard is suppose to protect you from this dastardly fellow? While you are at it, if you are going to light the place for him, why would he need that flashlight? Wouldn’t he be more conspicuous with it?

Sometimes these fixtures are called “night watchers” by those selling them. But, can a light watch the night? There is dinner to be had, reading, TV and homework to be done, baths to be taken, and yes even sleep. Whose eyes are watching to see what that trusty “night watcher” was illuminating – all – night – long? When was the last time you looked out your window in the night to see what your, or your neighbor’s “security” light, or a nearby streetlight, if a city dweller, is illuminating? If no one is watching, what is the point?

“Oh, Dastardly Dan will see the light, and that will certainly frighten him away” – you might say. Really? You think criminals are like cockroaches do you?

The word Lunatics comes from the time before artificial lighting, when all the bad and wild stuff that humans did at night happened near the full moon. Why? Because it is dangerous to wander around in the dark, that’s why. People tended to stay home at night with no moon until we invented streetlights. Ask yourself, if light deters crime why is crime the highest in our light polluted cities, or in days of yore on moonlight nights?

So, is Dan frightened or facilitated by your “night watcher”? Have you thought that maybe criminals are more like moths than cockroaches? Time for some facts:

1) Most burglaries occur in the day when the residents are away, and the burglars can see what they are doing and don’t look so conspicuous as Dastardly Dan with his flashlight. i

2) There is no credible evidence that simply lighting some place increases security. Indeed, it may just as well facilitate crime as discourage it. ii

3) Both experience and controlled studies alike have shown that outdoor lighting can increase crime, suggesting that criminals, like the rest of us, are afraid of the dark and need light to get around. iii

4) Lighting is best thought of as a safety device, to help people see what they are doing. It can be useful for security if there is a reasonable expectation of ongoing surveillance, not typically the case in a residential area at night. Even then, to be effective, proper lighting levels should be used, uneven lighting and shadows as well as light trespass avoided. In other words, real security lighting require design and planning. iv Your typical utility company security light is going to be thrown on an existing pole, send light in every direction only to peter out into shadows made worse by the unshield glare produced by a cheap fixture.

5) For residential security purposes, lighting on a motion sensor is more likely to be effective. Not only does it not attract or facilitate criminal intent but it signals possible detection when it comes on. v

So why do so many people pay for security lights? First, because utilities have heavily marketed “security” lighting to sell electricity at night when demand otherwise drops. Coal- fired power plants don’t have throttles. Perhaps this also explains why few offer motion sensors; they are selling electricity not security?

Second, because it is an easy sell. Humans, criminal and lawful alike, are out of our element in the dark. We natively fear it. light is good and darkness is evil. Lost in a wilderness, what would be the first thing we would want as night falls? The universality of leaving a little light on in the bedroom of a frightened child shows how ingrained the impulse is.

So, you see it’s not a security light, it is an insecurity light – a night light for grownups. Like a security blanket, a security light makes some of us feel better even though it has no actual benefit. So, the thief here is Ready Kilowatt who leads you to believe a light can protect your property and person. X dollars a month from your bank account to his, month after month, year after year for likely no purpose.

Of course, there are times and places where light is useful and has the very virtues we intuitively ascribe to it, such as porch and walkway lighting when expecting guests, driveway lighting on a motion sensor. Lighting in a parking lot or pedestrian way when in use. Premises security, if there is a security watch.

But just lighting some part of a yard or a street or parking lot all night every night of the year is not a rational thing to do. It not only cost money, but contributes to the degradation of our environment. It takes nearly a half-ton of coal to power one 100 watt bulb burning all day for a year. In turn, that generates almost a ton of carbon dioxide along with other air and water pollutants. There is growing evidence that lighting the night is impacting human health and altering the environment for other living things. vi

If you are really worried about crime, there are things you can do that are real like security systems. vii

Grow up, get smart, turn the night light off and use the money to light and protect your home properly. You will be safer, a little richer, the world less polluted and the stars closer.


i http://www2.fbi.gov/ucr/cius2009/data/table_07.html

ii A Report to the United States Congress, by the National Institute of Justice: “We can have very little confidence that improved lighting prevents crime, particularly since we do not know if offenders use lighting to their advantage.”

iii The Chicago Alley Lighting Project: Final Evaluation Report April 2000, Illinois Criminal Justice Information Center. http://www.icjia.state.il.us/public/pdf/ResearchReports/Chicago%20A lley%20Lighting%20Project.pdf. A controlled study comparing crime rates between lighted and unlighted Chicago alleys. Results showed a clear increase in all categories of crime, in the lighted alleys when compared to the same alleys before they were lighted and the unlighted comparison alleys.

Illumination Engineering Society, ES PR-33-14, 4.6.2, “lighting alone cannot provide security…increasing lighting levels does not necessarily increase security…A common error with security lighting is to assume that static lighting (lighting that is always on) is required…Using lighting that is controlled my motion sensors or similar devices which turn light on when a potential threat is detected can increase security.
http://www.dailygazette.com/weblogs/hartley/2011/nov/14/dimming-lights/ Reporting that towns in New York area turning down or off street lighting late at night to save money find crime falls.

http://jech.bmj.com/content/69/11/1118 British Journal of Epidemiology and Community Health. DOI: 10.1136/jech-2015-206012.

http://www.peninsula.wednet.edu/conservation/Energy/dark%20campus.htm A Washington state school district saves almost a million dollars a year on electricity by turning campus lighting off at night and finds vandalism and burglary drops to near zero.

iv Illumination Engineering Society, IESNA G-1-03

v Illumination Engineering Society, IESNA G-1-03 7.2.10

vi (AMA) REPORT 4 OF THE COUNCIL ON SCIENCE AND PUBLIC HEALTH (A-12) Light Pollution: Adverse Health Effects of Nighttime Lighting.

vii Crime Prevention Through Environmental Design, www.cpted.net

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