Our project is a 26-storey building located in Mexico City with more than 20 tenants. The HVAC consists of AHUs and VAV-boxes with recirculation at the AHU. I have several questions regarding the documentation required by this prerequisite and the requirements. We would appreciate some help:

1.Can we perform the VRP calculation including only the critical zone (meeting rooms) and disregarding other non-critical spaces?

2.Some floors do not comply with ASHRAE 62.1-2010 because small VAV-boxes were installed and do not provide the OA rates required by the calculator. Does the project fall under the Case 2? Can we comply with the prerequisite just measuring the outdoor air provided by the UMA and providing 10 cfm/person?

3.Is tenant ductwork a required documentation for certification? Many false ceilings are inaccesible and the plans cannot be drawn up.

4.Natural ventilation is no longer accepted as the only means of ventilation. Does it also apply to bathrooms? Does a naturally ventilated bathroom need an exhaust fan?

Thank you!