System and method of safe and effective energy usage and conservation for data centers with rack power distribution units

A system and method for improving usage and conservation of at least one air-management unit in a data center where a multiplicity of rack mounted power distribution units are used for power distribution to a multiplicity of electronic devices mounted on a plurality of racks in at least one computer room of the data center. A group of power load, temperature, humidity, and differential pressure sensors are provided throughout the racks, and coupled to a computer through a network interface for automatically calculating multiple air-management effectiveness and energy efficiency indices (e. g., rack cooling index RCI, rack humidity index RHI, rack airflow index RAI, rack differential pressure index RPI, and return temperature index RTI) based on the data from the sensors, such that the operation of the air-management unit can be adjusted accordingly to achieve an optimal efficiency of safe energy usage and conservation.