Ventilation for parking garage

Hi All, I have a question about a project under LEED certification. We are designing the ventilation of one floor below-grade parking garage, situated below an open area adjacent to an office building. The garage floor plan is of rectangular shape. There are no Full Time Equivalent in the parking garage (guard stations, and/or other occupied/occupiable spaces are not located in the garage, so the whole space is only for the purpose of parking and circulation). There is no mechanical ventilation. Openings for natural ventilation are provided. We would like to understand whether our design can be considered an alternative compliance path to ensure indoor air quality compliant with "Minimum Exhaust Rate" Table 6-4 of ASHRAE 62.1:2007 Note C " Exhaust not required if two or more sides comprise walls that are at least 50% open to outside". Openings for natural ventilation are evenly distributed on the roof of the garage (grade level). The overall surface of these openings to the outside is greater than 50% of the overall surface of two side walls. Also, an electronic CO monitoring system provides an alarm if the threshold of CO concentration achieves/exceeds 25ppm. As a result of an alarm, access to other vehicles to the garage is temporarily impeded until dilution/exhaust of contaminant through natural ventilation lowers CO concentration below the threshold. Can we implement such a compliance path in lieu of mechanical ventilation? Thank you