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: The operating underpressure PS- is the maximum value of the operating underpressure defined from a safety point of view by the manufacturer of the system for the various components in relation to the atmospheric pressure (1 bar) at the maximum permissible temperature TS1; Name: Max. permissible underpressure PS1- at TS1, room2