Description: time period during which all the performance requirements are met; Name: usefull life
Description: Time interval from first use until the instant when a limiting state is reached ; Name: useful life
Description: Group of components with the same construction features and the same structure, which - due to similar manufacturing techniques - can be collated for construction approval testing and class conformity controls. They are generally allocated to a construction type. Note: in certain cases, components can be viewed from various construction type specifications as belonging to the same type and, therefore, can be collated for construction approval and class conformity controls; Name: construction form of impeller