The Energy Policy Act (EPACT) of 1992 set standards for indoor water fixtures like toilets and faucets, which are used as a baseline for determining water savings in LEED projects. The 2005 amendment to the EPACT further updated these standards. References: LEED Green Associate Candidate Handbook, U.S. Green Building Council resources

A charrette is a strategy that can help build consensus for a project's sustainability goals. A charrette is an intensive, collaborative, and creative workshop that brings together the project team and other stakeholders to define the project goals, scope, and strategies. A charrette can help to establish a common vision, identify synergies, and prioritize actions for a green building project. A charrette can also foster communication, trust, and buy-in among the participants13. Reference: LEED v4 Green Associate Candidate Handbook1, LEED v4 BD+C Reference Guide3

The footprint of a building is the area of ground that it covers, defined by its perimeter. It's essentially the shape that results when you trace around the outer walls of a building plan. This term is used in architecture and urban planning to describe the space that a building occupies on a site. Reference: LEED Green Associate Candidate Handbook, U.S. Green Building Council resources

Prohibiting smoking near air exhausts is critical to maintain indoor air quality and occupant health. Smoke can infiltrate buildings through air intakes, compromising air quality and negating efforts to create a healthy indoor environment. LEED v4 guidelines emphasize such strategies under Indoor Environmental Quality credits. Smoking policies should align with green building practices to prevent the recirculation of contaminants.

Explanation
A closed system is a type of approach that promotes the conservation of materials and resources by linking elements in order to form relationships with their function1. A closed system is one that does not exchange matter or energy with its surroundings, and therefore minimizes waste and maximizes efficiency2. A closed system aims to achieve a circular economy, where resources are reused, recycled, or recovered, rather than disposed of3. A closed system can also enhance resource productivity, reduce environmental impacts, and foster innovation4.
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Zero Waste Definition
Closed system | physics
Material Resources, Productivity and the Environment
Sustainable Materials Management: The Road Ahead