[en] A method for calibration, testing and adjustment of dosimetric and radiometric equipment is suggested. The method ois based on the establishment of correlations between the measured value and the device indications in one part of the measurement range and on the interpolation of this value to other parts of the range studied. Two sources of ionizing radiation are used. The first source is adjusted so, that the device indication is within the calibrated part of the scale. The device indication and the siurce position are recorded and then the source is removed. The second source uis adjusted so, that the device indication is also within the calibrated part of the scale. The device indication is recorded. The first source uis instabled in the initial position. At that, the device indication corresponds to the sum of indications, recorded for the first and second sources separately and should be in the calibrated part of the scale. Varying the position of the second source in respect the detector the whole scale can be calibrated in a similar way. The method suggested is tested using neutron radiometers and gamma dosemeters. The method permits to decresase the number of source, required for the calibration, to exclude the necessity of their certification and to decrease considerably the requirements for the source characteristics