A first set of data is received relating to the operation of a first mechanical part. A plurality of steady state conditions for the first set of operational data is determined. A load history is determined for the first mechanical part based on the plurality of determined steady states and the first set of operational data. One of a plurality of predefined life consumption calculation models is selected based on a type of the first mechanical part and a position of a critical area at the first mechanical part. A level of life consumption for the critical area of the first mechanical part is determined based on the selected life consumption calculation model and the determined load history.