10/1/2012 ID# 10236
MPR/Prerequisite/Credit: SSc8: Light Pollution Reduction
Primary Rating System: New Construction v2009
Ruling
All instances in the credit language of "LEED project boundary" or "site boundary" shall be considered to refer to the "lighting boundary", for the purposes of this credit only. The lighting boundary is located at the property lines of the property, or properties, that the LEED project occupies. The lighting boundary can be modified under the following conditions:
-When the property line is adjacent to a public area that is a walkway, bikeway, plaza, or parking lot, the lighting boundary may be moved to 5 feet (1.5 meters) beyond the property line.
-When the property line is adjacent to a public street, alley or transit corridor, the lighting boundary may be moved to the center line of that street, alley or corridor.
-When there are additional properties owned by the same entity that are contiguous to the property, or properties, that the LEED project is within and have the same or higher lighting zone designation as the LEED project, the lighting boundary may be expanded to include those properties.

If the LEED project boundary is smaller than the property line, projects can use the lighting boundary to meet the light trespass requirements of this credit. Buildings that are part of campuses or shared properties can use the "campus boundary", i.e. the campus property line, to comply with the light trespass requirements of this credit. All LEED projects attempting SSc8 should continue to meet all exterior requirements (LPD, uplight, trespass) based all of the exterior luminaries within the LEED project boundary. The lighting boundary is only for the purposes of the trespass calculation, based on the light emitted by the luminaires within the LEED project boundary. Project teams should take note that the LEED project boundary must be appropriately defined and comply with Minimum Program Requirement (MPR) #3- "Must be a reasonable site boundary".

Street lighting that is required by governmental authorities to be installed within the LEED project, specifically for the purposes of lighting a public street, does not need to be included in any of the calculations. Project teams should provide documentation of the government requirement and a narrative describing the application of this exemption to the project.

Determination of the appropriate lighting zone is critical for this credit. For properties that contain sensitive areas (such as sleeping units or species habitats), the project must meet the light trespass requirements at the boundary of the sensitive area. An area is considered sensitive if it has a lower lighting zone designation than adjacent areas. If there are any parcels within the property that have a lower lighting zone designation, the exterior lighting requirements must be met at the lighting boundary of those areas.

Applicable Internationally.

***Update 1/1/13:This interpretation is written in an attempt to clarify the number of questions and ambiguities that exist around the 'lighting boundary'. This interpretation supersedes LI 1622, LI 2342, LI 5272 and LI 10114.