A new calibration has been developed for the electromagnetic flowmeters located on the 14-in. lines of the primary sodium coolant system of the Enrico Fermi Atomic Power Plant. This new calibration has incorporated the experimental hydraulic characteristics of the primary sodium coolant loop, the voltage outputs of the flowmeters on the 14- and 6-in. lines, and the original calibration of the flowmeters on the 6-in. lines. Utilizing this new calibration, the system pressure drop was found to vary as the 1.9'th power of the flow rate of the primary system. This relationship is in good agreement with theory.A comparison of the measured sodium flow using the new calibration with the calculated value from heat balance measurements showed good agreement, with an average deviation of 1.7%. (The“as-read”values from the flowmeters based on the previous calibration, which were developed using pump hydraulic characteristics and the pump affinity laws, were too high by an average of 10%.) This new calibration is now being used in the Fermi plant.