Description: ratio of the number of failures of a given category to a given unit of measure; Name: failure ratio
Description: Number of failures within a population divided by the number of life units used by that population; Name: failure rate
Description: norm/stipulation describing the explosion protection. The explosion protection type, the device category, the temperature class as well as the device / explosion group are taken from this norm. The type and number of the norm/stipulation with issue year and issue month must be given; Name: Reference norm of the explosion protection of the electric motor