LEED AP Building Design and Construction (BD+C) Practice Exam

For increased ventilation, what percentage must mechanically ventilated spaces increase outdoor air ventilation rates?

1. 20% above ASHRAE 62.1

2. 25% above ASHRAE 62.1

3. 30% above ASHRAE 62.1

4. 35% above ASHRAE 62.1

The correct answer is: 30% above ASHRAE 62.1

To enhance indoor air quality in mechanically ventilated spaces, increasing outdoor air ventilation rates is a key strategy. The correct answer indicates that outdoor air ventilation rates must rise by 30% above the minimum requirements set forth in ASHRAE Standard 62.1, which is the standard for ventilation in commercial buildings. This requirement is aligned with LEED standards, which emphasize improved indoor environmental quality through enhanced ventilation. By increasing ventilation rates, the intent is to dilute potential indoor pollutants more effectively, thus promoting occupant health and comfort. The 30% increase is a specific threshold that has been identified based on extensive research and recommendations within the field of building design. The other percentage options—20%, 25%, and 35%—do not align with the specific increment required for LEED certification under this particular criterion. It's vital for those involved in the design and construction of buildings to understand these thresholds to ensure that projects meet sustainable building goals effectively, thereby enhancing the overall indoor environment for occupants.