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FMEA Mil-STD-1629 Task 101 Component FMEA
  FMEA, Introduction
  Example 1: Mil-STD-1629 Piece Part FMEA
  Example 2: Mil-STD-1629 Criticality Analysis
  Example 3: Automotive FMEA
  General concerns with FMEA

This page explains the Mil-Std-1629, Task 101 FMEA. Mil-Std-1629 contains 5 FMEA types, called "tasks": Task 101, 102, 103, 104 and 105.
Mil-Std-1629 (Failure Mode and Effect Analysis) has been developed by US department of defense as a requirement for army material suppliers.

FMEA Mil-STD-1629 Task 101

It can be seen from the column headers that the item to be examined must be a machine or some other (hardware) equipment.
The main goal of this FMEA type is to collect and identify failure modes.
The table below describes the purpose of the columns in more detail.

Column header
Identification Number
A unique Identifier of the item. In most cases, but not necessarily, a number.
Item / Functional Identification (Nomenclature)
The name of the item.
A function of the item.
There may be more than one function per item (2)
Failure Modes and Causes
Potential failure modes of the function and potential causes.
Note: Most FMEA types offer separate columns for failure modes and causes.
There may be more than one failure mode or cause per function (3), and there may be more than one cause per failure mode.
Mission Phase / Operational Mode
The mission phase(s) or operational mode(s) for which the failure mode applies.
Depending on the nature of the item (aircraft, ground vehicle, submarine, ...), mission phases can be very different.
Failure Effects
The effects of the failure mode on various levels: Local effect (e.g. on circuit or component level), next effect (e.g. on PCB, assembly or subsystem level), and end effect (e.g. on system level).
For small systems, the next effect level may be omitted.
There may be more than one failure effect per failure mode (4).
Failure Detection Method
How will failures be detected? Failures may be detectable by diagnostics routine, or they may be self-evident. Sometimes, failures may be even undetectable.
Compensating Provisions
Measures (e.g. by design) in order to minimize the probability of failure modes, or to minimize potential consequences of failure modes.
Severity Classification
Qualitative classification of the severity of the failure mode or its consequences. There are usually 4 or 5 severity levels in military FMEAs, and 10 severity levels in automotive FMEAs.
A very important column. Put here everything that doesn't fit into the other columns, or which is important for other reasons. 

It can be seen from the column headers that this FMEA type has a qualitative nature, and its main goal is to collect failure modes.

The next example, task 102 of Mil-Std-1629, is rather a quantitative FMEA type.


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