Public Safety & Artificial Light
Monsters in the closet. The bogeyman under the bed. Criminals sneaking around in the dark. Our eyes need time to adjust to the darkness, until that happens, we can’t see into these dark corners or unlit alleyways. Nighttime for many people, especially children, bring feelings of anxiety and make imaginations run wild with scary scenarios. This fear of hidden dangers and the unknown, has led people to brighten the darkness to help ease fears and make the night feel safer. By adding night lights around the house, installing bright security lights on homes and buildings, or adding more light poles to streets and walkways, people experience less darkness and unknowns. But, does extra lighting actually make us safer or is it just to help ease our fears?
Do Brighter Nights Equal Safer Nights?
According to multiple studies done in the United States and United Kingdom over the last 25 years, there is no clear connection between more artificial outdoor lighting and less crime. In some cases, outdoor lighting can actually increase crime and make nighttime less safe. A 2015 study in the UK found that the amount of lighting had no effect on crime or car accidents, and a lighting project in Chicago found that bright alleyways were associated with increased crime rates.
Unshielded outdoor lights, where part or all of the lightbulb is visible, can also make victims of crime easier to see and give criminals more area to hide in. Unshielded lighting causes glare that is uncomfortable and blinding to the eyes and make it harder for people to see darker areas behind light fixtures. Looking at this image from amateur astronomer George Fleenor, you can see that this bright unshielded light is making the view behind the fence so dark that you can’t see the man standing there. When he shields the light from blinding his eyes, he can better see behind the fence.
Does this Mean we Should get rid of Outdoor Lighting?
No! There are ways that outdoor lighting can be improved upon so that it does help people be safe and feel safe. We may not be able to control what lights our towns or cities use, but we can make changes to lighting in our yards and even neighborhoods.
Fully shielded lights cover light bulbs, make all light shine directly to the ground, and reduce glare.
Lights should be dimmed or turned off when they are not needed or being used or use motion sensors if lights are needed at all times.
Reduce blue light by using bulbs that are a warm red or yellow tone.
Check out more on the International Dark Sky Association’s Outdoor Lighting Basics and My Neighbor’s Lighting pages!
Try this activity below to see how unshielded versus shielded lights change what you’re able to see around you!
Number of People Needed:
2 or more
Supplies:
A flashlight
1 physical image, object, or piece of paper with a message (per person)
A dark room
Directions:
Without showing anyone else, choose a physical object or image, or write a message on a piece of paper. Make sure to choose something that does not emit any light. Keep all of your objects hidden from everyone else until your turn.
Everyone sit on one side of the room.
Turn on the flashlight. Then, turn off all of the lights and make the room as dark as possible.
Taking turns, one person at a time will stand with the flashlight on the opposite side of the room.
Do not shine the flashlight directly in anyone’s face but aim the flashlight just above their heads. This will seem bright to the eyes. Have them feel free to squint, block the light with their hand, or anything else to make it more comfortable.
Then hold up your chosen object behind the flashlight.
Have everyone guess what object, image, or message you chose.
If they are unable to see the object have them try blocking the light with their hand.
Then hold the flashlight higher and aim the light at the ground.
Repeat the activity until everyone has had a turn to show their object.
Reflection Questions:
What was it like to try and guess the other object(s) without blocking the light? Was it uncomfortable to look at toward the unblocked light?
When you blocked the light, was it easier to see the object(s)?
Was the rest of the room hard to see when the light was shining at you? How about when the light was aimed at the ground?
Sources:
https://www.darksky.org/light-pollution/lighting-crime-and-safety/
https://cescos.fau.edu/observatory/lightpol-security.html
https://www.sciencealert.com/here-s-the-evolutionary-reason-why-we-re-afraid-of-the-dark
https://britastro.org/dark-skies/cfds_issues.php?topic=crime
http://jech.bmj.com/content/early/2015/07/08/jech-2015-206012
https://www.darksky.org/wp-content/uploads/2014/09/Chicago-Alley-Lighting-Project.pdf
http://www.darksky.org/our-work/lighting/lighting-for-citizens/lighting-basics/
https://www.darksky.org/our-work/lighting/lighting-for-citizens/my-neighbors-lighting/
By Amanda Leith
