Accreditation of Calibration Procedures for Specialised Measuring Instruments Utilized in Railway Transport; Selected Issues

Th e paper presents issues associated with the calibration and supervision of railway specifi c measuring instruments. It starts with considerations regarding the benefi ts associated with the measuring instruments calibration, especially regarding calibration performed by accredited laboratories. Attention is paid to the importance of maintaining traceability and keeping knowledge about measuring instruments’ errors in the context of railway transport safety. It analyses why the number of metrological laboratories off ering accredited calibration of railway specifi c instruments in Poland is insuffi cient. Th e paper makes use of the experience of the Railway Institute Metrological Laboratory. In particular, it uses experience gained in 2017 during the accreditation of AC resistance measurements, which are utilized for accredited measurements of the resistance of slippers with fastening systems, wheel wear profi le measurements with analogue callipers, buff er centre line height over rails running surface measurements and wheel tread diameter measurements based on two contact-points.