This prerequisite establishes a baseline for providing a minimum amount of outdoor air to buildings in order to maintain good indoor air quality and keep occupants comfortable and healthy. The prerequisite references ASHRAE 62.1-2007 (with errata but without addenda) and is often more stringent than local building codes, although it is not likely to entail any added costs.

Two cases, and you might need them both

The compliance paths for mechanically ventilated and naturally ventilated spaces, Case 1 and Case 2, are somewhat different and you may need to follow both paths for the same project on a space-by-space basis. Spaces served only by natural ventilation must follow the distinct requirements set out in Case 2, even if other spaces in the same building are mechanically ventilated and are following Case 1. Mixed-mode spaces which alternate between natural or mechanical ventilation must follow the compliance path for mechanical ventilation, Case 1.

Any ventilation systems serving the project are covered

Commercial interior projects will need to confirm that any ventilation systems serving the project meet the ventilation rates required by ASHRAE 62.1-2007, even if the ventilation system design itself is outside the scope of the project. If base building systems cannot be modified to meet the standard’s requirements, you will need to provide detailed analysis documenting the constraints and explaining why the base building systems cannot be upgraded. Systems must be able to provide at least 10 cfm per person to meet this prerequisite.