Glossary
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Incipient Failure
Definition(s)https://www.iadclexicon.org/wp-admin/post.php?post=4378&action=edit
Incipient Failure
Imperfection in the state or condition of an item so that a degraded or critical failure might (or might not) eventually be the expected result if corrective actions are not taken. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsIdle Time
Definition(s)
Idle Time
Part of the up time that an item is not operating. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsHidden Failure
Definition(s)
Hidden Failure
Hidden failure means a failure that is not immediately evident to operations or maintenance personnel and has the potential for failure of equipment to perform an on-demand function, such as protective functions in power plants and switchboards, standby equipment, backup power supplies or lack of capacity or performance.
Source: IMO MSC.1/Circ.1580, GUIDELINES FOR VESSELS AND UNITS WITH DYNAMIC POSITIONING (DP) SYSTEMS, 16 June 2017, International Maritime Organization. Regulatory GuidanceHidden Failure
A failure that is not immediately evident to operations or maintenance personnel and has the potential for failure of equipment to perform an on-demand function, such as protective functions in power plants and switchboards, standby equipment, backup power supplies or lack of capacity or performance.
Source: IMO MSC.1/Circ.1580, GUIDELINES FOR VESSELS AND UNITS WITH DYNAMIC POSITIONING (DP) SYSTEMS, 16 June 2017, International Maritime Organization. Regulatory GuidanceHidden Failure
Covert failure Dormant failure Unrevealed failure Undetected failure failure which is not immediately evident to operations and maintenance personnel- Note: 1 to entry: Hidden failures do not show themselves when they occur. The occurrence of a hidden failure gives a latent fault which may be revealed by specific tests (e.g. periodic tests) or by the failure of the item to performi ts function when required.
- Note: 2 to entry: The repair of hidden failures cannot begin as long as they have not been detected. The unknown times spent between the failures and their detections belong to the MTTRes.
Hidden Failure
Failure that is not immediately evident to operations and maintenance personnel. NOTE Equipment that fails to perform an “on demand” function falls into this category. It is necessary that such failures be detected to be revealed. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsGeneric Reliability Data
Definition(s)
Generic Reliability Data
Reliability data covering families of similar equipment. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsGeneric Reliability Data
reliability data covering families of similar equipment Note 1 to entry: See ISO 14224[15] for further details on equipment boundaries and equipment taxonomies that define these families of equipment within the petroleum, petrochemical and natural gas industries. Note 2 to entry: Plant-specific data on specific equipment could be part of generic reliability databases, but could differ a lot from generic data and should not be mixed with those. [SOURCE: ISO 14224] Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global StandardsFault
Definition(s)
Fault
Abnormal, undesirable state of a system element induced by the presence of an improper command or absence of a proper one, or by a failure- Note 1 to entry: All failures cause faults; not all faults are caused by failure.
- Note 2 to entry: System elements can include, for example, an entire subsystem, an assembly, or a component.
Fault
State of an item characterized by inability to perform a required function, excluding such inability during preventive maintenance or other planned actions, or due to lack of external resources. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsFault
State of an item characterized by inability to perform a required function, excluding the inability during preventive maintenance or other planned actions, or due to lack of external resources. NOTE A fault is often a result of a failure of the item itself but the state can exist without a failure. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsFault
inability to perform as required- Note 1 to entry: A fault of an item is a state, as distinct from a failure of an item which is an event (see Figure 8).
- Note 2 to entry: A fault of an item may result from a failure of the item or from a deficiency in an earlier stage of
- the life cycle, such as specification, design, manufacture or maintenance.
- Note 3 to entry: Qualifying terms may be used to indicate the cause of a fault, such as specification, design,
- manufacture, maintenance or misuse.
- Note 4 to entry: Inability to perform due to preventive maintenance, other planned actions, or lack of external
- resources does not constitute a fault.
- Note 5 to entry: Figure 8 illustrate the relationship between the concepts of failure and fault:
— The Failure x occurs at stage 1 and leads to the state Fault x which is not detected.
— from stage 2 point of view Fault x is a pre-existing fault.
— The Failure y occurs at stage 2 and lead to the state Faults x,y which is not detected.
— From stage 3 point of view Fault x,y is a pre-existing fault.
— and so on.
[SOURCE: IEC 60050 −191]
Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global Standards
Failure on Demand
Definition(s)
Failure on Demand
Failure occurring immediately when the item is solicited to start (e.g. stand-by emergency equipment). NOTE See also Clause C.6. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsNon-Refrigerated Tank
Definition(s)
Non-Refrigerated Tank
Container that stores material in a liquid state without the aid of refrigeration, either by evaporation of the tank contents or by a circulating refrigeration system. NOTE Generally, the storage temperature is close to, or higher than, ambient temperature. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsFailure Mode
Definition(s)
Failure Mode
Effect by which a failure is observed on the failed item. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsFailure Mode
Effect by which a failure is observed on the failed item. NOTE: See also B.2.6. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsFailure Mode
Effect by which a failure is observed on the failed item. NOTE Failure-mode codes are defined for some equipment classes in ISO 14224:2006, B.2.6. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsFracture Pressure
Definition(s)
Fracture Pressure
Force applied to the surface of a body divided by the original area of that surface. Source: API TR 5C3, Technical Report on Equations and Calculations for Casing, Tubing, and Line Pipe Used as Casing or Tubing; and Performance Properties Tables for Casing and Tubing, Upstream Segment, First Edition, December 2008. Global StandardsFailure Mechanism
Definition(s)
Failure Mechanism
Physical, chemical or other process that leads to a failure. NOTE See also B.2.2. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. GlobalStandardsFailure Data
Definition(s)
Failure Data
Specific equipment unit within an equipment class as defined by its boundary (e.g. one pump). Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. Global StandardsFailure Data
Data characterizing the occurrence of a failure event. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsFailure Cause or Root Cause
Definition(s)
Failure Cause or Root Cause
Circumstances associated with design, manufacture, installation, use and maintenance that have led to a failure. NOTE See also B.2.3. Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. Global StandardsFailure Cause
Circumstances during design, manufacture or use that have led to a failure. NOTE Generic failure cause codes applicable for equipment failures are defined in ISO 14224:2006, B.2.3. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsFailure
Definition(s)
Failure
Loss of structural integrity and/or transmission of fluid leakage through the wall of a component or a joint.Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global Standards
Failure
An occurrence in a component or system that causes one or both of the following effects:- loss of component or system function
- deterioration of functional capability to such an extent that the safety of the vessel, personnel or environment protection is significantly reduced.
Failure
Failure means an occurrence in a component or system that causes one or both of the following effects:- loss of component or system function; and/or
- deterioration of functional capability to such an extent that the safety of the vessel, personnel or environment protection is significantly reduced.
Failure
Loss of ability to perform as required. Source: ISO 16530-1:2017, Petroleum and natural gas industries — Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsFailure
The inability of a system or component to perform its required functions within specified performance requirements. From: NCSD Glossary. Source: NICCS™ Portal Cybersecurity Lexicon, National Initiative for Cybersecurity Careers and Studies (https://niccs.us-cert.gov/glossary) as of 11 November 2015, Global StandardsFailure
Loss of ability to perform as required Note 1 to entry: A failure of an item is an event, as distinct from a fault of an item, which is a state (see Figure 8). [SOURCE: IEC 60050 −191]
Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global Standards
Failure
Event causing an undesirable condition, e.g. loss of component or system function, or deterioration of functional capability to such an extent that the safety of the unit, personnel or environment is significantly reduced.- NOTE: Examples are structural failure (excessive yielding, buckling, rupture, leakage) or operational limitations (excessive riser tensioner stroke).
Failure
Any equipment condition that prevents it from performing to the requirements of the functional specification. Source: API SPEC 14A, Specification for Subsurface Safety Valve Equipment, Eleventh Edition, October 2005 (Reaffirmed June 2012). Global StandardsFailure
Event causing an undesirable condition, e.g. loss of component or system function, or deterioration of functional capability to such an extent that the safety of the unit, personnel or environment is significantly reduced.- EXAMPLE Structural failure (excessive yielding, buckling, rupture, leakage) or operational limitations (slick joint protection length, clearance).
Failure
Improper performance of a device or equipment that prevents completion of its design function. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global StandardsFailure
Termination of the ability of an item to perform a required function.- NOTE: 1 After the failure, the item has a fault.
- NOTE: 2 “Failure” is an event, as distinguished from a “fault,” which is a state.
- NOTE: 3 This concept as defined does not apply to items consisting of software only.
- NOTE: 4 See also Table B.1 and Clauses F.2 and F.3.
Failure
Termination of the ability of an item to perform a required function. NOTE 1 After failure, the item has a fault. NOTE 2 “Failure” is an event, as distinguished from “fault”, which is a state. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsError
Definition(s)
Error
Discrepancy between a computed, observed or measured value or condition and the true, specified or theoretically correct value or condition. NOTE 1 An error can be caused by a faulty item, e.g. a computing error made by faulty computer equipment. NOTE 2 The French term “erreur” can also designate a mistake. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsEquipment Unit
Definition(s)
Equipment Unit
Specific equipment unit within an equipment class as defined by its boundary (e.g. one pump). Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsEquipment Data
Definition(s)
Equipment Data
Technical, operational and environmental parameters characterizing the design and use of an equipment unit. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsEquipment Class
Definition(s)
Equipment Class
Class of similar type of equipment units (e.g. all pumps). NOTE Annex A describes a variety of equipment classes. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsDown Time
Definition(s)
Down Time
Time interval during which an item is in a down state. NOTE The down time includes all the delays between the item failure and the restoration of its service. Down time can be either planned or unplanned. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsDowntime
Time interval during which an item is in a non-working state. NOTE The downtime includes all the delays between the item failure and the restoration of its service. Downtime can be either planned or unplanned. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsDown State
Definition(s)
Down State
Internal disabled state of an item characterized either by a fault or by a possible inability to perform a required function during preventive maintenance. NOTE This state is related to availability performance (see 3.1). Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsDown State
Internal disabled state of an item characterized either by a fault or by a possible inability to perform a required function during preventive maintenance. NOTE This state is related to availability performance. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsDemand
Definition(s)
Demand
Activation of the function (includes functional, operational and test activation). NOTE For a more detailed description, see C.2.2. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsDegraded Failure
Definition(s)
Degraded Failure
Failure that does not cease the fundamental function(s), but compromises one or several functions. NOTE The failure can be gradual, partial or both. The function can be compromised by any combination of reduced, increased or erratic outputs. An immediate repair can normally be delayed but, in time, such failures can develop into a critical failure if corrective actions are not taken. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsCritical Failure
Definition(s)
Critical Failure
Failure of an equipment unit that causes an immediate cessation of the ability to perform a required function. NOTE Includes failures requiring immediate action towards cessation of performing the function, even though actual operation can continue for a short period of time. A critical failure results in an unscheduled repair. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsCorrective Maintenance
Definition(s)
Corrective Maintenancee
Maintenance carried out after fault recognition and intended to put an item into a state in which it can perform a required function. NOTE For more specific information, see IEC 60050-191:1990, Figure 191-10. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsCorrective Maintenance
Maintenance that is carried out after a fault recognition and intended to put an item into a state in which it can perform a required function. See IEC 60050-191:1990, Figure 191-10 [2], for more specific information. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsCorrective Maintenance
maintenance carried out after fault detection to effect restoration Note 1 to entry: Corrective maintenance of software invariably involves some modification. Note 2 to entry: Sometimes the corrective maintenance is also called curative maintenance. [SOURCE: IEC 60050‑191-46-06] Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global StandardsCommon-Cause Failure
Definition(s)
Common-Cause Failure
Failures of different items resulting from the same direct cause, occurring within a relatively short time, where these failures are not consequences of another. NOTE Components that fail due to a shared cause normally fail in the same functional mode. The term common mode is, therefore, sometimes used. It is, however, not considered to be a precise term for communicating the characteristics that describe a common-cause failure. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsCommon Cause Failure
Failures of different items resulting from the same direct cause, occurring within a relatively short time, where these failures are not consequences of each other. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsCommon Cause Failure
failures of different items, resulting from a single event, where these failures are not consequences of each other Note 1 to entry: It is generally accepted that the failures occur simultaneously or within a short time of each other. Note 2 to entry: Common cause failures can lead to common mode failures. Note 3 to entry: Common cause failures reduce the effect of system redundancy. Note 4 to entry: Explicit and implicit CCF are defined in 5.4.2. Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global StandardsBoundary
Definition(s)
Boundary
Interface between an item and its surroundings. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsBoundary
Software, hardware, or other physical barrier that limits access to a system or part of a system [9]. Source: ANSI/ISA–99.00.01–2007, Security for Industrial Automation and Control Systems, Part 1: Terminology, Concepts, and Models, 29 October 2007. National StandardActive Maintenance Time
Definition(s)
Active Maintenance Time
That part of the maintenance time during which a maintenance action is performed on an item, either automatically or manually, excluding logistic delays. NOTE 1 A maintenance action can be carried out while the item is performing a required function. NOTE 2 For a more detailed description and interpretation of maintenance times, see Figure 4 and Annex C. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsAvailability
Definition(s)
Availability
Ability of an item to be in a state to perform a required function under given conditions at a given instant or over a given time interval, assuming that the required external resources are provided.Source: DNVGL-RP-G108, Cyber security in the oil and gas industry based on IEC 62443, DNV GL, September 2017. Global Standards
Availability
Extent to which the system/structure/equipment is capable of retaining its functional integrity. Source: ISO 16530-1:2017, Petroleum and natural gas industries - Well integrity – Part 1: Life cycle governance, First Edition, March 2017. Global StandardsAvailability
The property of being accessible and usable upon demand. Extended Definition: In cybersecurity, applies to assets such as information or information systems. Adapted from: CNSSI 4009, NIST SP 800-53 Rev 4, 44 U.S.C., Sec 3542 Source: NICCS™ Portal Cybersecurity Lexicon, National Initiative for Cybersecurity Careers and Studies (https://niccs.us-cert.gov/glossary) as of 11 November 2015, Global StandardsAvailability
Fraction of time that a system (e.g. safety instrumented system, atmospheric-relief system, or flare-relief system) is able to perform the designated function if required for use.
Source:API STD 521, Pressure-relieving and Depressuring Systems, Sixth Edition, January 2014. Global StandardsAvailability
Property of being accessible and usable upon demand by an authorized entity. Source: ISO/IEC 27000:2014, Information technology — Security techniques — Information security management systems — Overview and vocabulary, Third Edition, January 2014. Global StandardsAvailability
Probability that a system will operate on demand. Source: International Association of Drilling Contractors, Appendix 2 to Health, Safety and Environment Case Guidelines for Offshore Drilling Contractors, Issue 3.3.2, February 2010. IADC GuidelinesAvailability
Ability of an item to be in a state to perform a required function under given conditions at a given instant of time or over a given time interval, assuming that the required external resources are provided. NOTE: For a more detailed description and interpretation of availability, see Annex C. Source: API STD 2000, Venting Atmospheric and Low-pressure Storage Tanks, Sixth Edition, November 2009. Global StandardsAvailability
The ability, measured in terms of uptime percentage, of a system to perform its required function. Source: OGP Report No. 415, Asset integrity – the key to managing major incident risks, International Association of Oil & Gas Producers, December 2008. Global StandardsAvailability
Ability of an item to be in a state to perform a required function under given conditions at a given instant of time, or in average over a given time interval, assuming that the required external resources are provided. Source: ISO 20815:2008, Petroleum, petrochemical and natural gas industries – Production assurance and reliability management. Global StandardsAvailability
Probability that an asset, under the combined influence of its reliability, maintainability, and security, will be able to fulfill its required function over a stated period of time, or at a given point in time.
Source: ANSI/ISA–99.00.01–2007, Security for Industrial Automation and Control Systems, Part 1: Terminology, Concepts, and Models, 29 October 2007. National Standard