Description: Period of time during which an item performs its intended function, it includes all the time a machine is continuously running from start-up until it is shut down.; Name: ot
Description: passed time period after comissioning of a system, sub-system, component or piping; Name: Operating time 
Description: maximum boundary value of temperature range in a specified temperature, in which an operating unit can be used, without serious changes of assigned features, depending on the exposure time. Temporal restrictions like short-time or durability have to be stated; Name: max. temperature range