Specifies the procedure to be used for the calibration of current-meters, i.e. for the experimental determination of the relationship between water velocity and rate of revolution of the rotating element. It also specifies the type of tank and equipment to be used and the method of presenting the results. The procedure does not take into account any possible differences existing between the behaviour of the current-meter moving in motionless water and that of a fixed current-meter in turbulent flow. It is identical with and has been reproduced from ISO 3455:1976.