FTA | Fault Tree Analysis
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Introduction
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Fault Tree Analysis (FTA) is a quantitative risk assessment methodology where the probability of a top event is calculated based on a combination of events happening at a lower-level. The top event is usually an undesired event (such as a system failure) to be avoided for a safer and more reliable system design. In contrast to the FMEA, FTA is a top-down approach.

A fault tree is composed of different types of nodes with a different function each. An OR gate is a node used to show that the output event occurs if one or more of the input events happen. An AND gate is a node in the fault tree demonstrating that the output event arises when all of the input events take place. 
Finally, a basic event is a node of the simplest event in a fault tree with its own rate of failure.

FTA is one of the most important analyses in the Safety field during the certification process. It takes as input the FMEA values and the output is used in the PSSA and SSA to demonstrate the fulfillment of the requirements.

Content
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The content of the FTA module is:

.. toctree::

    symbology.rst
    fta_diagram.rst
    computation.rst
    fta_treeview.rst
    fta_failure_conditions.rst
    fta_primary_table.rst
    fta_comments.rst
    fta_statistics_graphics.rst
    fta_import_export.rst
    fta_settings.rst