Testing and Balancing vs. BAS Measurement

Marc...to answer some of your questions...There are generally two types of testing that are commonly done: 1) verifying OA, usually at the AHU, for all systems (no sampling). The type of monitoring that your BAS does may or may not satisfy this criteria, depending on how direct a measure of OA it conducts and if it's happening at the right scale. 2) verifying the function of local exhaust systems (you must test all of them, but only have to provide documentation for a smattering). This could take the form of CFM reads, or just verification of fan speeds, voltage, control sequences, etc. And lastly, you need to provide evidence of PM activities for all system components, which is intended to take care of making sure VAV boxes or other components between the intake and exhaust systems are moving air around as intended. You don't actually have to take CFM readings at that level though.

How exactly is LEED defining exhaust systems? Does each fan CFM need to be tested or just each Outdoor Air Fan that supplies the exhaust fan CFM need to be tested?

An exhaust system is defined as a fan system that moves air from the interior and expels it to the exterior surroundings. All outdoor air INTAKES need to have at least one-time cfm measurements for the EBOM submittal. A separate requirement is to test the operation of all exhaust systems, but this generally does not require a cfm measurement. You just need to confirm that the exhaust system is functioning properly. For exhaust systems (including bathroom, shower, kitchen, and parking garage exhaust for example) the reference guide says, "The tests should confirm proper function, such as fan speed, voltage, control sequences, and setpoints, as applicable." For single restrooms with a small ceiling exhaust fan, my reviewer was okay with a physical inspection verifying that it was moving air -- without any voltage measurements, or fan speeds. We also verified that activating the control (thermostat, wall switch, etc.) starts the fan. I believe the preventive maintenance program is supposed to include all the exhaust fans as well as the systems that introduce ventilation air into the building.