From the 2022 NYC Mechanical Code:
Section 404 Enclosed Parking Garages
404.1 Enclosed Parking Garages
Where mechanical ventilation systems for enclosed parking garages operate intermittently, such operation shall be automatic by means of carbon monoxide detectors applied in conjunction with nitrogen dioxide detectors. Such detectors shall be installed in accordance with their manufacturers' instructions. Such systems shall operate automatically upon detection of a concentration of carbon monoxide of 25 parts per million (ppm) or nitrogen dioxide of 500 parts per billion (ppb).
404.2 Minimum Ventilation
Automatic operation of the system shall not reduce the ventilation airflow rate below 0.05 cfm per square foot of the floor area and the system shall be capable of producing a ventilation airflow rate of 0.75 cfm per square foot of floor area.
404.3 Occupied Spaces Accessory to Public Garages
Connecting offices, waiting rooms, ticket booths and similar uses that are accessory to a public garage shall be maintained at a positive pressure and shall be provided with ventilation in accordance with Section 403.3