Outdoor Air Mix

Mixed dry-bulb and humidity ratio from RA/OA states and OA fraction.

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Formula and source

Mixed-air dry bulb T_mix = (CFM_OA × T_OA + CFM_RA × T_RA) / (CFM_OA + CFM_RA). Outdoor-air ratio against ASHRAE 62.1 ventilation rates by occupancy.

ASHRAE 62.1-2022 (Ventilation for Acceptable Indoor Air Quality).

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