Glossary LEED V4(l)



a device emitting light in a fixture, excluding lamp housing and ballasts. Light-emitting diodes packaged as traditional lamps also meet this definition.


lamp life


the useful span of operation of a source of artificial light, such as bulbs. Lamp life for fluorescent lights is determined by testing three hours on for every 20 minutes off. For high-density discharge lamps, the test is based on 11 hours on for every 20 minutes off. Lamp life depends on whether the start ballast is program or instant. This information is published in manufacturers’ information. Also known as rated average life.


land trust


a private, nonprofit organization that, as all or part of its mission, actively works to conserve land by undertaking or assisting in conservation easement or land acquisition, or by its stewardship of such land or easements (Adapted from Land Trust Alliance)

その役割の全部または一部として、保全地役権、土地買収またはこれらの土地や地役権の管理において仕事を請負う、または援助することによって土地保全を活発にさせるのが主な業務、または業務の一部である民間組織、あるいは非営利組織のこと。(Land Trust Allianceより)

land-clearing debris and soil


materials that are natural (e.g., rock, soil, stone, vegetation). Materials that are man-made (e.g., concrete, brick, cement) are considered construction waste even if they were on site.


landscape water requirement (LWR)


the amount of water that the site landscape area(s) requires for the site’s peak watering month




a label, defined by U.S. EPA regulations under the Safe Drinking Water Act, that allows small amounts of lead in solders, flux, pipes, pipe fittings, and well pumps

米国 EPA 基準で定義されているSafe Drinking Water Actに基づく認証ラベルのことで、ハンダ、溶剤、配管、継手および井戸のポンプ等にはごく少量の鉛を含むことが許されている。

least-risk pesticide


a registered pesticide in the Tier III (lowest toxicity) category, using the San Francisco Hazard Ranking system, or a pesticide that meets the requirements in the San Francisco Pesticide Hazard Screening Protocol and is sold as a self-contained bait or as a crack-and-crevice treatment used in areas inaccessible to building occupants. Rodenticides are never considered least-risk pesticides.

San Francisco Hazard Ranking systemのTier III (毒性レベルの最低カテゴリー) に登録された殺虫剤、またはSan Francisco Pesticide Hazard Screening Protocol の要求を満たす殺虫剤。それらは殺虫効果のある餌の入った容器や、害虫が入り込む割れ目のような処理を施されて売られており、施設利用者が立ち入れないような場所で使われる。殺鼠剤はこの低リスク殺虫剤に含まれない。

length of stay


the amount of time a person remains in a health care facility as an admitted patient


life-cycle assessment


an evaluation of the environmental effects of a product from cradle to grave, as defined by ISO 14040–2006 and ISO 14044–2006

ISO 14040–2006およびISO 14044-2006 によって定義されている「揺りかごから墓場まで」タイプの製品における環境影響評価

life-cycle inventory


a database that defines the environmental effects (inputs and outputs) for each step in a material’s or assembly’s life cycle. The database is specific to countries and regions within countries.


light pollution


waste light from building sites that produces glare, is directed upward to the sky, or is directed off the site. Waste light does not increase nighttime safety, utility, or security and needlessly consumes energy.


light rail


transit service using two- or three-car trains in a right-of-way that is often separated from other traffic modes. Spacing between stations tends to be ½ mileor more, and maximum operating speeds are typically 40–55 mph (65–90 kmh). Light-rail corridors typically extend 10 or more miles (16 kilometers).

2輌または3輌編成の輸送サービスで、しばしば他の交通手段とは分けられる。駅間の距離は1/2マイル以上程度で、最大速度は一般的に40–55 mph (65–90 kmh) 程度である。典型的な線路長は通常10マイル(16km)以上である。

light trespass


obtrusive illumination that is unwanted because of quantitative, directional, or spectral attributes. Light trespass can cause annoyance, discomfort, distraction, or loss of visibility.


load shedding


an intentional action by a utility to reduce the load on the system. Load shedding is usually conducted during emergency periods, such as capacity shortages, system instability, or voltage control.


long-term bicycle storage


bicycle parking that is easily accessible to residents and employees and covered to protect bicycles from rain and snow


low-cost improvement


an operational improvement, such as a repair, upgrade, or staff training or retraining. In LEED, the project team determines the reasonable upper limit for low-cost improvements based on facility resources and operating budgets.


low-impact development (LID)


an approach to managing rainwater runoff that emphasizes on-site natural features to protect water quality, by replicating the natural land cover hydrologic regime of watersheds, and addressing runoff close to its source. Examples include better site design principles (e.g., minimizing land disturbance, preserving vegetation, minimizing impervious cover), and design practices (e.g., rain gardens, vegetated swales and buffers, permeable pavement, rainwater harvesting, soil amendments). These are engineered practices that may require specialized design assistance.