Glossary
Selected key terms pertaining to medical device development are listed below with References.
Key Terms
There are currently 11 key terms in this directory beginning with the letter F.
failure criticality
combination of the severity of an effect and the frequency of its occurrence or other attributes of a failure as a measure of the need for addressing and mitigation
[IEC 60812:2006]
failure mode and effects analysis (FMEA)
a technique by which the consequences of an individual failure mode are systematically identified and evaluated
Note 1: FMEA is an inductive technique using the question “What happens if ... ?”. Components are analysed one at a time, thus generally looking at a single-fault condition. This is done in a “bottom-up” mode, i.e. following the procedure to the next higher functional system level.
Note 2: FMEA is commonly divided into three types:
1. Design FMEA (DFMEA) – FMEA that considers failure modes associated with product design (i.e., assuming product meets product design specifications and product is used as intended)
2. Application FMEA (AFMEA) – FMEA that considers failure modes associated with product use (i.e., assuming product meets product design specifications but product is subject to use errors)
3. Process FMEA (PFMEA) – FMEA that considers failure modes associated with the production process or other operations process
Note 1: FMEA is an inductive technique using the question “What happens if ... ?”. Components are analysed one at a time, thus generally looking at a single-fault condition. This is done in a “bottom-up” mode, i.e. following the procedure to the next higher functional system level.
[ISO/TR 24971:2020]
Note 2: FMEA is commonly divided into three types:
1. Design FMEA (DFMEA) – FMEA that considers failure modes associated with product design (i.e., assuming product meets product design specifications and product is used as intended)
2. Application FMEA (AFMEA) – FMEA that considers failure modes associated with product use (i.e., assuming product meets product design specifications but product is subject to use errors)
3. Process FMEA (PFMEA) – FMEA that considers failure modes associated with the production process or other operations process
failure mode effects and criticality analysis (FMECA)
extension to FMEA that includes a means of ranking the severity of failure modes to allow prioritization of countermeasures
Note: Analogous to FMEA, the three types of FMECA are: DFMECA, AFMECA, and PFMECA.
Note: Analogous to FMEA, the three types of FMECA are: DFMECA, AFMECA, and PFMECA.
fault tree analysis (FTA)
an organized graphical representation of the conditions or other factors causing or contributing to the occurrence of a defined undesired outcome, referred to as the "top event"
Note 1: Fault tree analysis is a deductive (top-down) method of analysis aimed at pinpointing the causes or combinations of causes that can lead to the defined top event. The analysis can be qualitative or quantitative, depending on the scope of the analyses.
Note 2: When the outcome is a success, then the fault tree becomes a success tree, where the input events are those that contribute to the top success event.
Note 1: Fault tree analysis is a deductive (top-down) method of analysis aimed at pinpointing the causes or combinations of causes that can lead to the defined top event. The analysis can be qualitative or quantitative, depending on the scope of the analyses.
Note 2: When the outcome is a success, then the fault tree becomes a success tree, where the input events are those that contribute to the top success event.
[IEC 61025:2006 modified]
finished device
any device or accessory to any device that is suitable for use or capable of functioning, whether or not it is packaged, labeled, or sterilized
Note: A device that is a constituent part of a combination product is considered a finished device within the meaning of the QS regulation.
[FDA 21CFR820]
Note: A device that is a constituent part of a combination product is considered a finished device within the meaning of the QS regulation.
[FDA 21CFR4]
foreign exporter
[organization that] exports or offers for export to the United States (U.S.), a device manufactured, prepared, propagated, compounded, or processed in a foreign country, including devices originally manufactured in the United States. A foreign exporter must have an establishment address outside the U.S.
[FDA website: Who Must Register...]
fully refurbishing
for the purposes of the definition of manufacturer, means the complete rebuilding of a device already placed on the market or put into service, or the making of a new device from used devices, to bring it into conformity with this Regulation, combined with the assignment of a new lifetime to the refurbished device
[EU MDR 2017/745, EU IVDR 2017/746]
functional analysis (FA)
systematic identification of the functional structure of a medical system, including system boundaries (interfaces), functional inputs, and functional outputs
functional input
material, energy, or information that is delivered to a medical device or medical system during use
Note: Functional inputs can be divided into two categories:
1. Intended Functional Inputs - functional inputs inherent to the intended use
2. Unintended Functional Inputs - functional inputs not inherent to the intended use (i.e., environmental disturbances delivered to the medical device or medical system)
Note: Functional inputs can be divided into two categories:
1. Intended Functional Inputs - functional inputs inherent to the intended use
2. Unintended Functional Inputs - functional inputs not inherent to the intended use (i.e., environmental disturbances delivered to the medical device or medical system)
functional output
material, energy, or information that is delivered from a medical device or medical system during use
Note: Functional outputs can be divided into two categories:
1. Intended Functional Outputs - functional outputs inherent to the intended use
2. Unintended Functional Outputs - functional outputs not inherent to the intended use (i.e., environmental disturbances delivered from the medical device or medical system)
Note: Functional outputs can be divided into two categories:
1. Intended Functional Outputs - functional outputs inherent to the intended use
2. Unintended Functional Outputs - functional outputs not inherent to the intended use (i.e., environmental disturbances delivered from the medical device or medical system)
Medical device developers are strongly encouraged to consult the listed reference for each key term to fully understand the context behind the definition and its intended application.
Definitions from the FDA Code of Federal Regulation (CFR) are listed without dates and are accurate through December 2020. Consult the listed FDA reference (online) to confirm the latest definition.