(methodologies)= # Part 1 - Methodologies This part explains the framework and taxonomy used in the ECSS-Q-HB-30-02A handbook and links it to the reliability prediction process and usage. It provides guidance for users that are in charge of planning a prediction. The *taxonomy* is defined on two major axes: 1. The *type of elements* ({term}`EEE`, mechanical, and miscellaneous elements) 2. The *{term}`failure root causes `* (random, systematic, degradation, and extrinsic failures), see {numref}`Figure_methodo_0` for an overview. Moreover, this part describes the general *reliability prediction framework* and how it should be used. A number of *ground rules and assumptions* are described which should be agreed upon before starting a prediction. This includes the *scope and focus* in terms of failure root causes to be covered in a prediction for a specific use. Finally, the use of predictions during the *project life cycle* is adressed. ```{figure} pictures/methodo_figure1.png --- width: 600px name: Figure_methodo_0 --- Classification of failures by root cause ``` This part contains the following paragraphs: ```{tableofcontents} ```