Pol06 Reduction of nighttime light pollution

(2 credits available; 1 exemplary)

Aim

To ensure that external lighting is concentrated in the appropriate areas and that upward lighting is minimised, thereby reducing unnecessary light pollution and nuisance to residents and neighbouring assets.

Question

Has an assessment been performed that demonstrates that external lighting does not result in light pollution at night?

Credits	Answer	Select a single answer option, Answer E can only be selected if Answer C has been selected
0	A	Question not answered
0	B	No
2	C	Yes, qualitative assessment performed
2	D	Exterior lighting is not provided, and it is not required from a safety perspective
Exemplary	E	Yes, quantitative assessment performed by a lighting professional

Assessment criteria

Criterion	Assessment criteria	Applicable answer
1	For qualitative assessments where external lighting is present:  All external lighting is aimed downwards, to avoid upward sky glow. All external lighting is aimed away from residents’ internal habitable areas, neighbouring buildings or open spaces, or has screens or baffles to prevent light spill to them.  There are no illuminated signs. Lighting is automatically controlled to be switched off or dimmed to a much lower level between 23:00 and 07:00 (the curfew period).	C
2	A lighting professional confirms that external obtrusive lighting has been eliminated through effective design that removes the need for external lighting without adversely affecting the safety and security of the site and the residents.	D
3	For quantitative assessments where external lighting is present, a lighting professional confirms:  All external lighting (except for safety and security lighting) complies with the pre-curfew limitations in Table 33 and can be automatically switched off between 23:00 and 07:00 (the curfew period).  Illuminated signs, where present, comply with the maximum luminance (cd/m²) in Table 33. If safety or security lighting is installed and is used between 23:00 and 07:00, it complies with the post-curfew limitations in Table 33 (e.g. by using an automatic switch to reduce the lighting levels at 23:00 or earlier).	E
4	Assessment of illuminance or luminous intensity is not required if all luminaires are cut-off types and angled so that light in potentially obtrusive directions is blocked. Assessment of upward light ratio is not required if all luminaires are cut-off types delivering downward light only.	C-E
5	Flush stud lights used for safety purposes in vehicle manoeuvring areas may be excluded from the assessment.	C-E
6	All types of illuminated sign must meet the criteria, both self-illuminated and those illuminated by reflection from other sources.	C-E
7	For the purposes of this issue, external lighting includes both lighting mounted externally, and lighting mounted inside an asset that is primarily intended to enhance its external appearance or light external spaces after dark.	C-E

Methodology

Quantitative assessment by lighting professional

The direct measurement of upward light ratio (ULR), vertical illuminance and luminous intensity may not be possible due to issues with access to luminaires or to neighbouring properties. Consequently, the lighting professional may use their professional judgement to determine compliance with the requirements in Table 33, e.g. visual assessment to estimate the proportion of ULR, or where access to sensitive receptors is not possible, luminous intensity measurements could be made from accessible locations in the direction of the view of luminaires as seen from sensitive receptors. Where lighting design documentation is available from when the lighting was installed, this may be used to demonstrate compliance with the assessment issue criteria.

Checklists and Tables

Table 33: Obtrusive light limitations for exterior lighting installations and illuminated signs

Table 34: Environmental lighting zones

Evidence

Criteria	Evidence requirement
-	The evidence below is not exhaustive, please also refer to the ‘BREEAM evidential requirements’ section in the scope of the Guidance for appropriate evidence types which can be used to demonstrate compliance.
All	Night-time lighting levels report or any other relevant study.
All	Photographic evidence confirming that external luminaires are designed to restrict upward light and light spill.
All	Confirmation that lighting is switched off during the curfew period.

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