These notes emphasise the environmental benefits of reducing sky glow and `light pollution' from upward scattering of artificial light, including road and street lighting, and provide specific guidelines. Simple ways for reducing the problems of unnecessary intrusive light include: (1) switching off light when not required for safety and security; (2) where possible, directing light downward to illuminate its target; (3) if upward light direction is necessary, reduce its spillage through intelligent use of shields and baffles; (4) use specifically designed equipment that minimises the spread of light above the horizontal; and (5) do not use light in the excess of requirements. Six more technical recommendations are also made, which can help lighting engineers and other experts on lighting to reduce light pollution further. Relevant lighting standards and guides are listed.
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