The Solutions
Urban Night Sky Project

Know the solutions
Take 5 for the night:
Guidelines and Principles leading to Best Practice
- Light only what is needed
- Use energy efficient bulbs and only as bright as necessary
- Shield lights within the fixture and direct them down to the subject area
- Use light only when it’s needed – don’t leave them burning all night
- Choose warm white light bulbs – 3000k or less. They are a wise eyes choice that are better for our health.
Image credit: Kerryville Public Utility Board.
Take 3 for starters
- DECREASE the k’s – the kelvins. Check the number on the light bulb pack. Aim for 3000K or less. That means warm white rather than cool white – it’s kinder for our eyes and better for our circadian rhythm because it emits less blue light which can suppress melatonin production and mess with our sleep cycles.
- DIRECT light down, to protect the night from skyglow and light trespass. The only way to ensure this happens is to fully shield light fixtures, which enable light to directed to where its need most.
- DIM lights where possible, means lower power settings and/or using motion sensors are good options. Saving energy and saving money, while reducing glare, sound like sensible ideas – win-win-win.


What's in / What's out
Getting a handle on what’s best and what’s worst, this illustrated guide (see left) is a useful visual presentation of what makes for a good choice and what makes for a choice that simply perpetuates the problem and makes things worse. Choose right, buy right, protect the night. Pass on the knowledge. Be an influencer, with a multiplier effect.
Australasian Dark Sky Alliance (ADSA) has produced an approved lighting guide.
Why ADSA Approved lighting? The Australasian Dark Sky Alliance (ADSA) is dedicated to reducing light pollution. The ADSA Approved light fittings listed on this site, conform with dark sky principles specific to Australasian standards and guidelines including AS/NZS 4282:2019 and the Australian Federal National Light Pollution Guidelines for Wildlife.
This list should be used as a tool for councils, designers and end-users who are looking at installing new lighting systems or upgrading existing lighting installations, that are considerate of the night sky, ecosystems, wildlife and human health and comfort.
It is important that dark sky principles tie back in to the universally agreed 5 principals of dark sky sensitive lighting – timing, direction, glare, spectral composition and shielding. BUY RIGHT – LIGHT RIGHT – PROTECT THE NIGHT
A model code for planning and policy development
Dark Sky Planning Guideline – Protecting the observing conditions at Siding Spring
4.2 The design principles – pages 20-26
Principle 1 Light must have a clear purpose
Principle 2 Eliminate upward spill light
Principle 3 Direct light downwards and avoid light trespass
Principle 4 Use shielded fittings
Principle 5 Avoid excess lighting
Principle 6 Switch lights off when not needed
Principle 7 Use energy efficient bulbs
Principle 8 Use asymmetric beams
Principle 9 Direct lights away from reflective surfaces
Principle 10 Use warm white colours
…………………………………………………………………….
Night Sky: Glossary – page 27
Artificial skyglow is that part of the night sky’s brightness that is caused by human-made sources of light.
Colour temperature is the perceived colour of a light source ranging from cool (blue) to warm (yellow), measured in degrees Kelvin (K). A low colour temperature such as 2,500 K will have a warm appearance, while 6,500 K will appear cold and harsh.
Light pollution means the brightening of the night sky caused by artificial light.
Light trespass happens when the spill light is cast where it is not wanted.
Lumens are a measure of light output from a bulb. The quantity of lumens a bulb produces is independent of the wattage. Some types of bulb are more energy efficient than others and produce more lumens per watt.
Natural skyglow is that part of the night sky’s brightness that is caused by radiation from the stars and moon and luminescent processes in the Earth’s upper atmosphere.
Shielded light fitting means a light fitting that does not allow light to shine above the horizontal plane and prevents light trespass. If a develop-ment will use a fitting that is not shielded, some form of permanent physical opaque shield must be used to stop light trespass. This can be a cover or part of a building. Adjacent surfaces, if they are lightly coloured, must also be shielded to stop excessive reflected light from adding to skyglow. The shielding should be constructed to minimise emissions in the 10 degrees below horizontal.
Skyglow is the brightness of the night sky caused by the cumulative impact of reflected radiation (usually visible light), scattered from the constituents of the atmosphere in the direction of observation. Skyglow has 2 separate components: natural and artificial skyglow.
Spill light is light that falls outside the boundaries of the object intended to be lit. Spill light serves no purpose and, if directed above the horizontal plane, contributes directly to artificial skyglow.
Wattage is the amount of electricity needed to light a bulb. Generally, the higher the wattage, the brighter the light will be and the more lumens it will produce.
Extracts from:
Dark Sky Planning Guideline – Protecting the observing conditions at Siding Spring.
https://www.planning.nsw.gov.au/sites/default/files/2023-03/dark-sky-planning-guideline.pdf
REFERENCES FOR RESEARCH
Responsible Outdoor Light at Night (ROLAN)
Outdoor lighting guideline – Factsheet
https://www.clarence.nsw.gov.au/files/assets/public/v/1/building-and-development/files/factsheets/factsheet_outdoor_lighting_guideline_april_2018.pdf
goodbad_lighting
http://www.adelaideobservatory.org/darkskysa/goodbad_lighting.html
Streetlights and Floodlights – Ausgrid
https://www.ausgrid.com.au/In-your-community/Streetlights
Lighting Design Techniques for Reducing Light Pollution – Plasgain
https://plasgain.com.au/lighting-design-techniques-for-reducing-light-pollution/
Lighting-Council-Australia-LED-Buyers-Guide.pdf
https://www.lightingcouncil.com.au/wp-content/uploads/2018/12/Lighting-Council-Australia-LED-Buyers-Guide.pdf
Colour Temperature Explained – Guides & Examples
https://reductionrevolution.com.au/blogs/how-to/colour-temperature?srsltid=AfmBOoro284DAqvsPOz86K-qk6OOROSr_IGvq89jWevdXG2M6fqGOzIg
The Ultimate Guide To Lighting Colour Temperature – Lighting Style
https://www.lightingstyle.com.au/guide-to-lighting-colour-temperature.html
Guidelines and Principles leading to Best Practice
Five Principles for Responsible Outdoor Lighting | DarkSky International
https://darksky.org/resources/guides-and-how-tos/lighting-principles/
Guide to Dark Sky Friendly Products and Best Practices – ASD Lighting PLC
https://asdlighting.com/guide-to-dark-sky-friendly-products-and-best-practices/
ADSA Approved Lighting | ADSA
https://www.australasiandarkskyalliance.org/adsa-approved
Site and area Outdoor luminaires | Signify
https://www.signify.com/en-ca/products/outdoor-luminaires/site-and-area
EcoForm LED lighting | Gardco | Signify
https://www.signify.com/en-us/brands/product-highlights-new/products/gardco/ecoform-led
Night Matters | DarkSky International – watch past webinar presentations on a range of subjects
https://darksky.org/what-we-do/events/night-matters/