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OS does not automatically assign a humidity/RH setpoint. In many cases, and especially throughout California and much of the western/arid US, humidity is often neglected when designing HVAC systems. In these cases, only a dry-bulb temperature setpoint/schedule is necessary to specify in order to do a load calculation. Of course, there will be humidity, depending on the outside air moisture content, the amount of ventilation air supplied by the system, and internal source of moisture, but that does not make it neccessary to control for humidity; it is perfectly acceptable to control for only dry-bulb air temperature. For example, all of the DOE/PNNL commercial prototype models do not control for humidity, except for a single zone in Outpatient Healthcare (Floor 1 Operating Room 1).

OS does not automatically assign a humidity/RH setpoint. In many cases, and especially throughout California and much of the western/arid US, humidity is often neglected when designing HVAC systems. In these cases, only a dry-bulb temperature setpoint/schedule is necessary to specify in order to do a load calculation. Of course, there will be humidity, depending on the outside air moisture content, the amount of ventilation air supplied by the system, and internal source of moisture, but that does not make it neccessary necessary to control for humidity; it is perfectly acceptable to control for only dry-bulb air temperature. temperature, except perhaps for critical space types such as operating rooms and other spaces where humidity control is required. For example, all of the DOE/PNNL commercial prototype models do not control for humidity, except for a single zone in Outpatient Healthcare (Floor 1 Operating Room 1).