Last month focused on problems created by light pollution affecting the health of plants, animals and even us. Reducing light pollution can sometimes be relatively simple by becoming aware of what to look for when buying outdoor lighting products.
Using five Principles for Responsible Outdoor Lighting to Reducing Light Pollution
DarkSky International and the Illuminating Engineering Society (IES) in 2020 published five Lighting Principles for Responsible Outdoor Lighting. These five principles are easy to understand:
Responsible outdoor lighting needs to be:
1) Useful – Light only when and if the light will be useful
2) Targeted – Aim and shield the light source so light is directed only where it is needed
3) At low light levels – the least amount (no brighter than) needed for the purpose
4) Controlled – by timers and/or motion activation and dimmers
5) Warm-colored – using lights with low color temperature
Targeted lighting can be achieved by using shielded light fixtures designed to cast the light directly onto the target area with a minimum amount of light aimed at areas outside the target.
Low light levels enable us to see the area, while avoiding excessive light levels that do not provide any additional benefit.
Controlled lighting employs devices such as timers, dimmers and motion-activated lighting where the light is limited to when needed and in the lowest amount necessary.
Color temperature: Lights with high color temperature contain more blueish wavelength light, causing a greater likelihood of increased light pollution. Low color temperature lights are warmer – more on the yellow or orange part of the spectrum, and result in less light pollution.
Light Pollution Control in Connecticut Laws and Regulations
In 2001, a state law was enacted to require all streetlights to be fully shielded to reduce light pollution. In 2004, a Light Pollution Control requirement was adopted as part of the State Building Code, requiring commercial projects to use fully shielded outdoor lighting. In 2006, a new law was approved requiring all outdoor lighting at state properties to be fully shielded. At the local level, a number of municipalities, including Suffield, now incorporate light pollution control requirements as a part of the municipality’s zoning regulation. Most recently, in 2023, a new law was adopted to require state agencies to turn off their outdoor lighting from 11p.m until 5 a.m.
Street Lighting
Much of the street lighting in Suffield is unnecessary from the perspective of crash avoidance. Clear lane markings and roadside reflectors can often improve safety for road travel. Suffield would be well served by adopting a Streetlight Master Plan to identify the specific conditions to justify a streetlight at a given location. For streets with low traffic volume during late night/early morning hours (everywhere in Suffield), programmable photocells can be used to turn the streetlight off at 11 p.m. and back on at 5 a.m. In the alternate, photocells can automatically reduce light output from streetlights by 50% during these late night hours.
As climate change increasingly becomes a greater concern, and the need to reduce our carbon footprint becomes more acute, the judicious use of outdoor lighting, using the five Principles for Responsible Outdoor Lighting, is one small, yet important, step in conserving energy and reducing our carbon footprint.