Seeing Stars

Trawsfynydd (© Keith O'Brien)

alt=Ty Cipar Llyn Conwy (© Keith O'Brien)

Lighting - Basic Guidelines

Living or working in a Dark Sky Reserve does not mean turning off all lights! Rather, it encourages us to use lights which are more environmentally friendly, of better quality, more effective in throwing light where it is needed, but also reduces light pollution and carbon emissions and is also better for night wildlife.

What is light pollution?

There are three types of light pollution

  • Sky glow - which lights up the night sky and impairs our view of the stars
  • Glare - which can blind us in a dark place
  • Light trespass - light spilling beyond the area being lit.

Each of these kinds of light pollution can

  • cause unnecessary disruption to our lives
  • Waste money
  • Waste electricity
  • Contribute to the production of greenhouse gases

How can I help?

We need external lighting for a number of reasons, including for security and business purposes. The IDA (International Dark-Sky Association) recognizes this but encourages us to be cautious wise in the use of external lighting.

To minimize the harmful effects of light pollution,

  • Lights should be switched on only when needed
  • Only light the area that needs it
  • Light should not be brighter than necessary
  • Minimize blue light emissions
  • Use lights that are fully shielded and pointing downwards.

The most important thing to remember:

Think before switching on

Is this necessary?

If so, is it too bright? Does it interfere with others?

Our officers are available to provide advice to developers on the type of suitable external lighting.

The examples below provide a simple guide to the type of lights that are unacceptable and the type of lights which reduce pollution, glare and light trespass.