LEED AP with Operations and Maintenance (O+M ) Practice Exam

When performing ventilation rate procedure calculations for EQ prerequisite Minimum IAQ Performance, under what condition should the calculations run?

1. Cooling mode

2. Heating mode

3. Ventilation mode

4. Dehumidification mode

The correct answer is: Heating mode

In the context of the ventilation rate procedure for the Indoor Air Quality (IAQ) Performance prerequisite, the calculations should generally be performed under heating mode. This is because heating mode conditions provide insight into how the ventilation system operates during colder months, when outdoor air is introduced to the building for fresh air exchange. It is crucial to ensure that the building can maintain acceptable indoor air quality while managing energy efficiency and thermal comfort in these conditions. Using heating mode for the calculations ensures that the HVAC system’s capacity to filter outdoor air and prevent drafts is adequately evaluated, reflecting the true performance of the system in the operating environment most likely to lead to problems with air quality if not properly managed. Performing these calculations in other modes, such as cooling, ventilation, or dehumidification, may not provide a complete picture of the air handling system’s performance under the varied conditions that exist during typical heating demands. Hence, focusing on heating mode is vital for assessing compliance with minimum IAQ performance standards effectively.