LEED-AP-BD+C Exam Dumps : LEED AP Building Design + Construction (LEED AP BD+C)

The outdoor airflow rate is the amount of outdoor air that is supplied to the building by the ventilation system to dilute indoor air pollutants and provide fresh air for the occupants.  The outdoor airflow rate depends on the ventilation standard that the project follows, which can be either ASHRAE 62.1-2010 or CEN Standard EN 15251-2007 1 . Both standards specify the minimum outdoor airflow rate per person and per unit area for different occupancy types and zones. Therefore, increasing the number of occupants will require an increase in the outdoor airflow rate to maintain the minimum ventilation level. The other variables, such as supply air velocity, system ventilation efficiency, and supply air temperature set point, do not directly affect the outdoor airflow rate, although they may influence the energy consumption and thermal comfort of the ventilation system.

The heat island effect is the phenomenon of urban areas having higher air temperatures than surrounding rural areas due to the absorption and emission of heat by human-made surfaces, such as buildings, roads, and pavements. The heat island effect can have negative impacts on the environment, human health, and energy consumption. One of the strategies to reduce the heat island effect is to use highly reflective paving materials that have a high solar reflectance index (SRI), which measures the ability of a surface to reflect solar radiation and stay cool. However, over time, the paving materials can accumulate dirt and dust, which can lower their reflectance and increase their heat absorption. Therefore, a facility manager cleaning highly reflective paving material is reducing the heat island effect by restoring the reflectance and cooling potential of the surface12.