English, 11 pages, 14 figures, 13 references
Keywords: approval, calibration test, velocity measurement

Before approving speed measurement devices the PTB conducts substantial calibration tests. One crucial point of these tests is comparative readings in real traffic with a PTB reference system for speed measurement. These tests cover the speed and vehicle spectrum with several thousand readings, and these are supplemented by special type specific analyses. In addition, approving the instruction manual is also part of the approval procedure: with precise instructions the instruction manual must specify the usage of the device in order to rule out misreadings or the wrong allocation of measured values. In this way the instruction manual becomes a central source of information on the evaluation of specific measurement situations, even for the expert.