Lighting
Why Light Pollution Matters
A growing body of research suggests that uncontrolled outdoor lighting has caused serious harm to the environment and human health. Apart from hiding the stars, excessive lighting has harmful effects on:
Nocturnal animals
Migrating birds
Sea turtle hatchlings
Insects
Humans
Before the advent of electric light in the 20th century, our ancestors experienced a night sky brimming with stars that inspired science, religion, philosophy, art and literature including some of Shakespeare's most famous sonnets.
The common heritage of a natural night sky is rapidly becoming unknown to the newest generations. In fact, millions of children across the globe will never see the Milky Way from their own homes.
We are only just beginning to understand the negative repercussions of losing this natural resource.
LED: Why 3000K or Less - 3000 Kelvin Shielded LED Lights Have Quickly Become the Standard for Outdoor Lighting.
From
International Dark Sky Association press release, 2015 April 9:
Good Lighting Doesn't Compromise Safety & Security
There is no clear scientific evidence that increased outdoor lighting deters crime. It may make us feel safer but it does not make us safer. The truth is bad outdoor lighting can decrease safety by making victims and property easier to see.
Glare from overly bright, unshielded lighting creates shadows in which criminals can hide. It also shines directly into our eyes, constricting our pupils. This diminishes the ability of our eyes to adapt to low-light conditions and leads to poorer nighttime vision, dangerous to motorists and pedestrians alike.
Another serious side effect of light pollution is wasted energy. Wasted energy costs money, contributes to greenhouse gas emissions and climate change, and compromises energy security.
Does More Lighting = More Safety?
A June 5, 2004, Des Moines Register headline reads: “Darkened Streetlights Fail To Raise Crime Rate.” The article goes on to explain how, in an effort to save the city-and thus, taxpayers-nearly three-quarters of a million dollars a year, the city shut off thirty-nine percent of its higher-wattage streetlights along main thoroughfares. The result? A few concerned shop owners and police, but numbers that didn’t support their fear: a 3.5 percent drop in crimes like vandalism, burglary, and robbery. Shocked? You shouldn’t be.
The Problem
... We all want a secure home, of course; but the methods which were once thought to be tried and true no longer hold. The ancient dogma of “more light is better” has prevailed for so long that we’ve completely ignored what actually works. Several studies by respected authorities have been done on the subject, and the results may surprise you.
The Studies
Back in 1977, the US Department of Justice set out to evaluate the relationship between lighting and crime, and concluded in their Phase I Final Report that “…while there is no statistically significant evidence that street lighting impacts the level of crime, especially if crime displacement is taken into account, there is a strong indication that increased lighting-perhaps lighting uniformity-decreases the fear of crime” (National Institute of Law Enforcement and Criminal Justice, July 1977).
Some of those Des Moines residents have certainly substantiated that fear of crime, absent abhorrable lighting levels: the Register article remarked that “…others remain unconvinced that the move [to extinguish 39% of its street lights] was a good idea, no matter how much money it saved.” It seems as if some citizens are still afraid of the dark…
When one thinks about it, a decrease in fear of crime without a corresponding decrease in actual crime is a risky affair; allowing oneself to be lulled by the illusion of safety disarms us of our natural instincts for self-protection.
The Institute of Justice, which replaced the National Institute, followed up on the 1977 study, and in their 1997 report added that, “We may speculate that lighting is effective in some places, ineffective in others, and counter-productive in still other circumstances. The problematic relationship between lighting and crime increases when one considers that offenders need lighting to detect potential targets and low-risk situations (Fleming and Burrows, 1986). Institute of Justice, “Preventing Crime: What Works, What Doesn’t, What’s Promising,” 7-32.
U.S. agencies aren’t the only ones interested in the subject. In 2002, Australian researchers delivered a critical review to a parliamentary committee on drugs and crime in the state of Victoria, Australia.
In summary, the project concluded that “lighting certainly allays the fear of crime, but the overwhelming balance of scientific evidence from relatively short-term field studies is that lighting does not effectively deter violence or property crime, contrary to the beliefs of some crime prevention practitioners.” “Correctly moderated outdoor ambient light levels are expected to reduce crime in due course” (Outdoor Lighting and Crime, Clark, 2002).
Industry Enlightenment
Chuck Genre of the Center for Advanced Public Safety Research addressed the “more light is better” myth in a recent CPTED (Crime Prevention Through Environmental Design) newsletter article, asserting that “Intuitively, it may seem that more light is better. Unfortunately, this is not the case. Too much light degrades visual performance.” “One of the lasting truths of CPTED lighting is that quality of light is just as important as the quantity of light,” Genre asserts.
CPTED holds an annual conference to discuss current and emerging methods for reducing crime, and lighting technique is often one of the hottest topics. This year’s meeting will be held in Brisbane, Australia, and is themed “People & Safer Communities: The CPTED Advantage.” Check out the “Meetings” section of this issue for more information.
The Illuminating Engineering Society of North America-the most respected technical lighting group in the US-has also addressed the issue. The IESNA published a new document in 2003: G-1: Security Lighting for People, Property, and Public Spaces. It warns against over lighting and especially glare; according to the IESNA, “glare causes annoyance, discomfort, or loss in visual performance or visibility, and usually reduces the benefits of security lighting.” (13)
The above is from International Dark Sky Association newsletter #59
The following from International Dark-Sky Association -- Information Sheet 51
Lighting and Crime
Does outdoor nighttime lighting prevent crime? The answer is nobody knows. There have been studies in the United States and in Europe examining this issue, and they have come to no definite conclusions that can be applied to society as a whole. Some studies suggest that lighting a particular neighborhood or park reduces the local crime rate. These types of studies often suffer from poor controls, poor scientific methodology, and failure to include long term follow-up. Other studies show no significant change in crime rates after the installation of lighting. If it were so easy to reduce crime with lighting, then we should have made considerable headway by now. Our cities have never been brighter, yet the crime rate is higher than ever. The connection between crime reduction and increased lighting is vague at best.
It is safe to say that good lighting in a park, neighborhood, or shopping mall may indeed bring more people out for shopping and recreation. If this is the case, there may be less crime, as more people are present. On the other hand, harsh excessive lighting with glare may give a trashy wasteland appearance to a street or neighborhood causing people to automatically associate it with a high crime rate area. Think about how many places there are in our big cities that are brilliantly overlit and devoid of pedestrians.
There are anecdotal reports of increased crime and vandalism after the installation of lights. An article in Building Operator (see IDA Information Sheet 54) discusses how school districts across the country are actually turning off lights on school grounds to reduce vandalism. This also saves money by reducing energy use. There is no scientific evidence that nighttime blackout of lighting will always reduce vandalism, just as there is no evidence increased nighttime lighting necessarily reduces crime. A poorly conceived lighting program instituted by public hysteria over crime and vandalism can cause more harm than good. It often inflames public passions and magnifies the problem out of proportion to its true size. It offers people a solution that won't be effective, giving the public a false sense of security, and it wastes funds that could be spent on other social needs, such as more police or a better recreation program for school dropouts.
Is there the a public need for nighttime lighting? Of course there is. Numerous studies demonstrate reduced automobile and pedestrian accidents on properly lit busy roads and arterioles. Reasonable lighting levels are necessary for urban living. However, quiet suburban neighborhoods probably do not need any street lights whatsoever, or at most, lights only at busy corners. Malls and shopping center parking lots need reasonable lighting levels during business hours. After hours, the lighting levels can be greatly reduced or the lights entirely turned off. As in all cases with outdoor nighttime lighting, the lighting must be well thought out and well designed for the tasks at hand, keeping in mind the need for public security and recreation as well as the need to protect the beauty of the nighttime sky.