Description: mathematical expectation of the operating time between failures; Name: mtbf
Description: expectation of the operating time between failures; Name: mean time between failures (MTBF)
Description: The norm in fixed relation to the feature being described. This defines the parameters that influence the contents of the correlated feature. Type and number of the norm with issue year and issue month must be given, e.g. DIN ISO 4711:YYYY-MM.; Name: Reference norm of the coating, room1