Summary:

In the Geodesy Metrology Laboratory of the AGH University of Science and Technology in Krakow (GLM AGH) are conducted research associated with checking, validation and calibration of surveying equipment. Using a laser inter-ferometer as a standard of length measure significantly increased the range of works performed in GLM AGH. There was built a vertical comparator that allows precise calibration of leveling rods (with classic and barcode graduation), hori-zontal comparator allowing to calibrate invar or steel tapes, test of total stations, electronic distance measuring instruments and levels, as well as the thermal chamber to determine the coefficient of linear thermal expansion of leveling rods. Research capabilities of GLM AGH complement observation stands to the classifi-cation of survey instruments, including precise digital levels, electronic theodolites, and to study stability of collimation's line of instruments. For testing EDM, total stations and GPS receivers is used calibration baseline "Wisła" and polyline cali-bration base.
The paper characterizes the various measurement stands and shows the range of possible tests of geodetic instruments performed in GLM AGH. Based on the results of research work for the surveying contractors, quotes numerous exam-ples proving the necessity of periodically checking the instruments and the benefits for the accuracy of geodetic measurements.