ASHRAE 62.1 is a standard that ensures adequate ventilation is supplied to building occupants. ASHRAE stands for the American Society of Heating, Refrigerating and Air-ConditioningEngineers, a professional organization that develops standards and guidelines for the design, operation, and maintenance of buildings.
ASHRAE 62.1 is a standard that specifies the minimum ventilation rates and other measures for new and existing buildings that are intended to provide acceptable indoor air quality (IAQ) for the occupants.
Ventilation is the process of supplying outdoor air to or removing indoor air from a building. Adequate ventilation is important for maintaining good IAQ, which can affectthe health, comfort, and productivity of the occupants13. References: LEED v4 Green Associate Candidate Handbook1, ASHRAE's Standard 62.13

Graywater refers to relatively clean wastewater from domestic activities such as washing dishes, laundry, and bathing. Water from lavatory faucets falls into this category. Graywater can be treated and reused for non- potable purposes such as toilet flushing or irrigation, which can help conserve water. References: LEED Green Associate Candidate Handbook, U.S. Green Building Council resources

Paved surfaces absorb and retain heat, increasing local temperatures and contributing to the heat island effect.
LEED encourages mitigating this effect by using materials with high Solar Reflectance Index (SRI) or implementing strategies like green roofs and shaded areas.

According to a study completed by the Heschong Mahone Group, providing increased daylighting in schools can improve student test scores by 7%-18%. Daylighting is the practice of placing windows, skylights, other openings, and reflective surfaces so that sunlight (direct or indirect) can provideeffective internal lighting.
Particular attention is given to daylighting while designing a building when the aim is to maximize visual comfort or to reduce energy use. References: LEED Green Associate Candidate Handbook, U.S. Green Building Council resources

Systems thinking is a principle that is part of the integrated process, which is a collaborative and holistic approach to green building design, construction, and operation. Systems thinking involves understanding the interrelationships and interactions among the various components of a system, such as the building, its occupants, its site, its climate, and its energy sources. Systems thinking helps to identify synergies, optimize performance, avoid unintendedconsequences, and create multiple benefits for the project13. References:
LEED v4 Green Associate Candidate Handbook1, LEED v4 BD+C Reference Guide3