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A few different types of FMEA analyses exist, such as

 Functional
 Design, and
 Process FMEA.

Sometimes FMEA is extended to FMECA to indicate that criticality analysis is performed too.

FMEA is an inductive reasoning (forward logic) single point of failure analysis and is a core
task in reliability engineering, safety engineering and quality engineering. Quality engineering
is especially concerned with the "Process" (Manufacturing and Assembly) type of FMEA.

A successful FMEA activity helps to identify potential failure modes based on experience with
similar products and processes - or based on common physics of failure logic. It is widely used
in development and manufacturing industries in various phases of the product life cycle. Effects
analysis refers to studying the consequences of those failures on different system levels.

4. 1. Main Rules of FMEA

The ground rules of each FMEA include a set of project selected procedures; the assumptions
on which the analysis is based; the hardware that has been included and excluded from the
analysis and the rationale for the exclusions. The ground rules also describe the indenture level
of the analysis, the basic hardware status, and the criteria for system and mission success. Every
effort should be made to define all ground rules before the FMEA begins; however, the ground
rules may be expanded and clarified as the analysis proceeds. A typical set of ground rules
(assumptions) follows:

 Only one failure mode exists at a time.
 All inputs (including software commands) to the item being analyzed are present and at

nominal values.
 All consumables are present in sufficient quantities.
 Nominal power is available

4. 2. Advantages of FMEA

Major benefits derived from a properly implemented FMEA effort are as follows:

 It provides a documented method for selecting a design with a high probability of
successful operation and safety.

 A documented uniform method of assessing potential failure mechanisms, failure
modes and their impact on system operation, resulting in a list of failure modes ranked
according to the seriousness of their system impact and likelihood of occurrence.

 Early identification of single failure points (SFPS) and system interface problems,
which may be critical to mission success and/or safety. They also provide a method of
verifying that switching between redundant elements is not jeopardized by postulated
single failures.

 An effective method for evaluating the effect of proposed changes to the design and/or
operational procedures on mission success and safety.

GiDB|DERGi Sayı 5, 2016