Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Background Load
Definition(s)
Background Load
Background load means operational discharges from the facility. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceBalanced and Comprehensive Picture
Definition(s)
Balanced and Comprehensive Picture
Balanced and comprehensive picture means all external and internal incidents that the facility is vulnerable to should be identified. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceBallast Control Operator (BCO)
Definition(s)
Ballast Control Operator (BCO)
Ballast Control Operator (BCO) means the person assigned responsibility for the normal day-to-day control of trim, draught and stability. Source: IMO Resolution A.1079(28), Recommendations for the Training and Certification of Personnel on Mobile Offshore Units (MOUs), Adopted on 4 December 2013, International Maritime Organization, Regulatory GuidanceBallast Water
Definition(s)
Ballast Water
“Ballast Water” means water with its suspended matter taken on board a ship to control trim, list, draught, stability or stresses of the ship. Source: International Convention for the Control and Management of Ships’ Ballast Water and Sediments, 2004. LegislationBallast Water
Ballast water is water used to maintain the stability of an offshore facility. In typical practice, ballast water is segregated from ship’s bilge and should not be contaminated with oil. Source: Offshore Waste Treatment Guidelines, The Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada-Nova Scotia Offshore Petroleum Board, and National Energy Board, Canada, December 15, 2010. Regulatory GuidanceBallast Water Discharge
Definition(s)
Ballast Water Discharge
“Ballast Water Discharge” means the ballast water as would be discharged overboard. Source: Resolution MEPC.169(57), revised Procedure for approval of ballast water management systems that make use of Active Substances (G9), 4 April 2008, International Maritime Organization. Regulatory GuidanceBallast Water Management Plan
Definition(s)
Ballast Water Management Plan
Ballast Water Management Plan - is the document referred to in regulation B-1 of the Convention describing the ballast water management processes and procedures on board individual ships. Source: Resolution MEPC.140(54), Guidelines for approval and oversight of prototype ballast water treatment technology programmes (G10), 24 March 2006, International Maritime Organization. Regulatory GuidanceBallast Water Management System (BWMS)
Definition(s)
Ballast Water Management System (BWMS)
Ballast Water Management System (BWMS) means any system which processes ballast water such that it meets or exceeds the ballast water performance standard in regulation D-2. The BWMS includes ballast water treatment equipment, all associated control equipment, monitoring equipment and sampling facilities. Source: Resolution MEPC.174(58), revised Guidelines for approval of ballast water management systems (G8), 10 October 2008, International Maritime Organization. Regulatory GuidanceBallast Water Tank
Definition(s)
Ballast Water Tank
“Ballast Water Tank” – means any tank, hold, or space used for the carriage of ballast water. Source: Resolution MEPC.124(53), Guidelines for ballast water exchange (G6), 22 July 2005, International Maritime Organization. Regulatory Guidance Source: Resolution MEPC.127(53), Guidelines for ballast water management and development of ballast water management plans (G4), 22 July 2005, International Maritime Organization. Regulatory Guidance Source: Resolution MEPC.149(55), Guidelines for ballast water exchange design and construction standards (G11), 13 October 2006, International Maritime Organization. Regulatory GuidanceBallast Water Tank
“Ballast Water Tank” – means any tank, hold or space used for the carriage of ballast water as defined in Article 1 of the Convention. Source: Resolution MEPC.149(55), Guidelines for sediment reception facilities (G1), 13 October 2006, International Maritime Organization. Regulatory Guidance Source: Resolution MEPC.209(63), 2012 Guidelines on design and construction to facilitate sediment control on ships (G12), 2 March 2012, International Maritime Organization. Regulatory GuidanceBallast Water Treatment Equipment
Definition(s)
Ballast Water Treatment Equipment
Ballast Water Treatment Equipment means equipment which mechanically, physically, chemically, or biologically processes, either singularly or in combination, to remove, render harmless, or avoid the uptake or discharge of harmful aquatic organisms and pathogens within ballast water and sediments. Ballast water treatment equipment may operate at the uptake or discharge of ballast water, during the voyage, or at a combination of these events. Source: Resolution MEPC.174(58), revised Guidelines for approval of ballast water management systems (G8), 10 October 2008, International Maritime Organization. Regulatory GuidanceBarge Supervisor (BS)
Definition(s)
Barge Supervisor (BS)
Barge Supervisor (BS) means a person who may provide support to the offshore installation manager (OIM) in certain essential marine matters. The barge supervisor on some MOUs may be referred to as the stability section leader, barge engineer or barge master. Source: IMO Resolution A.1079(28), Recommendations for the Training and Certification of Personnel on Mobile Offshore Units (MOUs), Adopted on 4 December 2013, International Maritime Organization, Regulatory GuidanceBarrier
Definition(s)
Barrier
Envelope of one or several well barrier elements preventing fluids from flowing unintentionally from the formation into the wellbore, into another formation or to the environment.
Source: ABS Guide for Classification and Certification of Managed Pressure Drilling Systems, September 2017. Global StandardsBarrier
Functional grouping of safeguards or controls selected to prevent a major accident or limit the consequences- Note 1 to entry: Barriers can be subdivided into hardware barriers or human barriers and are supported by management system elements.
- Note 2 to entry: Adapted from IOGP Report No. 415.
Barriers
Obstacle to prevent flow whose performance can be verified.
Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global StandardsBarrier
A risk control that seeks to prevent unintended events from occurring, or prevent escalation of events into incidents with harmful consequences. For process safety, further reference to barriers can be found in OGP Reports No. 415 and No. 456. Source: IOGP Report No. 510, Operating Management System Framework for controlling risk and delivering high performance in the oil and gas industry, International Association of Oil & Gas Producers, June 2014. Global StandardsBarrier
Component or practice that contributes to the total system reliability by preventing formation fluid or gas flow. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global Standards Source: API Bulletin 97, Well Construction Interface Document Guidelines, First Edition, December 2013. Global StandardsBarrier
In this RP, barriers are defined as components or practices that contribute to the total system reliability to prevent or stop formation fluid or gas flow. Source: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsBarriers
“Barrier” means any fluid, plug or seal that prevents gas or oil or any other fluid from flowing unintentionally from a well or from a formation into another formation (barrière). Source: Canada Oil and Gas Drilling and Production Regulations, SOR/2009-315, February 2013. Regulations Source: Nova Scotia Offshore Petroleum Drilling and Production Regulations, SOR/2009-317, Canada, current to May 31, 2012. RegulationsBarrier
Barriers as mentioned in the first subsection, can consist of either physical or non-physical measures, or a combination. The requirement for independence as mentioned in the second subsection, means that it should not be possible for multiple important barriers to be impaired or malfunction simultaneously, e.g. as a result of a single fault or a single incident. Barriers can also be measures designed to prevent or limit the spread of acute pollution. Source: Guidelines Regarding the Management Regulations, Norway, updated December 2012. Regulatory GuidanceBarrier
Technical, human or organizational safeguards that are put in place to prevent, mitigate or control health, safety or environmental risks. Incident Reporting and Investigation Guidelines, The Canada-Nova Scotia Offshore Petroleum Board and Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada, November 30, 2012. Regulatory GuidanceBarrier
Element forming part of a pressure-containing envelope which is designed to prevent unintentional flow of produced/injected fluids, particularly to the external environment. Source: API RP 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, Fourth Edition, Reaffirmed 2011. Global StandardsBarrier
One or several barrier elements that are designed to prevent unintended flow of formation fluid. Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global StandardsBarriers
The term barrier is defined as meaning any fluid or any plug or seal that prevents hydrocarbons or any other fluid from flowing unintentionally from a formation, into another formation, or unintentionally flowing from a well. Source: Drilling and Production Guidelines, The Canada-Nova Scotia Offshore Petroleum Board and Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada, March 31, 2011. Regulatory GuidanceBarriers
Barrier means any fluid, plug or seal that prevents petroleum or any other fluid from flowing unintentionally from a well or from a formation into another formation. Source: Drilling and Production Guidelines, The Canada-Nova Scotia Offshore Petroleum Board and Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada, March 31, 2011. Regulatory GuidanceBarriers
A functional grouping of safeguards, such as primary containment, process equipment, engineered systems, operational procedures, management system elements, or worker capabilities designed to prevent LOPC and other types of asset integrity or process safety events, and mitigate any potential consequences of such events. A set of barriers is also often referred to as a risk control system. Source: OGP Report No. 456, Process Safety – Recommended Practice on Key Performance Indicators, International Association of Oil & Gas Producers, November 2011. Global StandardsBarrier
Measure which reduces the probability of releasing a hazard’s potential for harm or which reduces its consequences. (Barriers are Controls or Defences.) The hierarchy of barriers is:- prevention,
- detection,
- control,
- mitigation,
- emergency response.
Barrier
A functional grouping of safeguards and controls selected to prevent the realization of a hazard. Each barrier typically includes a mix of: plant (equipment), process (documented and ‘custom and practice’) and people (personal skills and their application). The selected combination of these ensures the barrier is suitable, sufficient and available to deliver its expected risk reduction. Source: OGP Report No. 415, Asset integrity – the key to managing major incident risks, International Association of Oil & Gas Producers, December 2008. Global StandardsBarrier
Measure which reduces the probability of realizing a hazard’s potential for harm and which reduces its consequence.- NOTE Barriers may be physical (material, protective devices, shields, segregation, etc.) or non-physical (procedures, inspection, training, drills, etc.)
Barrier
A functional grouping of safeguards and controls selected to prevent realization of a hazard. Source: OGP Report No. 415, Asset integrity – the key to managing major incident risks, International Association of Oil & Gas Producers, December 2008. Global StandardsBarriers During Drilling
Definition(s)
Barriers During Drilling
Example of barriers during drilling: primary well barrier is drilling fluid column and secondary barrier elements are casing, casing cement, wellhead, BOP etc. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceBarriers During Production
Definition(s)
Barriers During Production
Example of barriers during production: primary well barrier elements are SCSSV, production packer & completion string. Secondary barrier elements include Christmas tree, tubing hanger, wellhead, casing and cement. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceBaseline Risk
Definition(s)
Baseline Risk
The normal operating condition level of risk that takes into account existing risk mitigation measures.
Source: API RP 781 Security Plan Methodology for the Oil and Natural Gas Industries.1st Ed. September 2016. Global StandardsBaseline Risk
Current level of risk that takes into account existing risk mitigation measures.
Source:API STANDARD 780, Security Risk Assessment Methodology for the Petroleum and Petrochemical Industries, First Edition, May 2013. Global StandardsBaseline Risk
Current level of risk that takes into account existing risk mitigation measures. Sample Usage: Risk analysts for the locality calculated a baseline risk value before analyzing the risk reduction potential of two alternative strategies. Annotation: Often, the word ―risk‖ is used to imply ―baseline risk‖ with the unstated understanding that the reference is the current circumstances. It should not be confused with risk as a measurement, which can change with the substitution of different variables. Source: DHS Risk Lexicon, U.S. Department of Homeland Security, 2010 Edition. September 2010 Regulatory GuidanceBayesian Probability
Definition(s)
Bayesian Probability
The process of evaluating the probability of a hypothesis through 1) the specification of a prior probability and 2) modification of the prior probability by incorporation of observed information to create an updated posterior probability. Sample Usage: The analyst applied Bayesian probability techniques to incorporate new evidence and update her estimate of the threat probability. Annotation: This concept is also referred to as Bayesian probabilistic inference. Bayesian probability evaluates likelihoods as probabilities rather than frequencies. Source: DHS Risk Lexicon, U.S. Department of Homeland Security, 2010 Edition. September 2010 Regulatory GuidanceBayesian Probability (Subjective Probability)
Definition(s)
Bayesian Probability (Subjective Probability)
Interpretation or estimate of probability as a personal judgment or ―degree of belief‖ about how likely a particular event is to occur, based on the state of knowledge and available evidence Sample Usage: Analysts use their knowledge of terrorist strategies, objectives, and capabilities in combination with evidence from operations to estimate a subjective probability of 10 percent for an attack to occur within the next five years. An analyst may use Bayesian probability to estimate likelihood based on a degree of belief. Annotation:- Like all probabilities, subjective probability is conventionally expressed on a scale from zero to one where zero indicates the event is impossible and one indicates the event has or certainly will occur.
- Within the subjective probability interpretation, it is possible to estimate probabilities of events (using experts or models) that have not previously occurred or that have only rarely occurred, such as acts of terrorism. However, because subjective probabilities incorporate historical or trial data when available, the subjective probability will approximate the frequentist probability as data becomes more plentiful.
- Subjective probability is currently one of the most common uses of probability among statisticians and the risk analysis community.
- Bayesian probability is colloquially used as a synonym for subjective probability. In statistical usage, Bayesian probabilistic inference is an approach to statistical inference that employs Bayes’ theorem to revise prior information using evidence.
BCO
Definition(s)
BCO
Ballast Control Operator Source: IMO Resolution A.1079(28), Recommendations for the Training and Certification of Personnel on Mobile Offshore Units (MOUs), Adopted on 4 December 2013, International Maritime Organization, Regulatory GuidanceBDV
Definition(s)
BDV
Blow-Down Valves. Source: NOPSEMA Guidance Note: Control Measures and Performance Standards, N-04300 GN0271, Australia, Revision 3, December 2011. Regulatory GuidanceBilge Alarm
Definition(s)
Bilge Alarm
An alarm which indicates an abnormally high level of bilge water. Source: IMO resolution A.1021(26), Code on Alarms and Indicators, 2009, 18 January 2010, International Maritime Organization. Regulatory GuidanceBilge Water
Definition(s)
Bilge Water
Bilge water is typically composed of seawater that may seep or flow into an offshore installation from various points in the structure, and may also be contaminated with oil and other substances from machinery spaces. Source: Offshore Waste Treatment Guidelines, The Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada-Nova Scotia Offshore Petroleum Board, and National Energy Board, Canada, December 15, 2010. Regulatory GuidanceBiofouling
Definition(s)
Biofouling
Biofouling means the accumulation of aquatic organisms such as micro-organisms, plants, and animals on surfaces and structures immersed in or exposed to the aquatic environment. Biofouling can include microfouling and macrofouling (see below. Source: Resolution MEPC.207(62), 2011 Guidelines for the control and management of ships' biofouling to minimize the transfer of invasive aquatic species, 15 July 2011, International Maritime Organization. Regulatory GuidanceBlock Section
Definition(s)
Block Section
"Block section" means the cross-sectional area (m2) of the catalyst block based on the outer dimensions. Source: Resolution MEPC.198(62), 2011 Guidelines addressing additional aspects to the NOx Technical Code 2008 with regard to particular requirements related to marine diesel engines fitted with Selective Catalytic Reduction (SCR) Systems, 15 July 2011, International Maritime Organization. Regulatory GuidanceBlowout
Definition(s)
Blowout
Uncontrolled flow of well fluids and/or formation fluids from the wellbore to the surface or into lower pressured subsurface zones (underground blowout). Source: API Specification 16Q, Design, Selection, Operation, and Maintenance of Marine Drilling Riser Systems, Second Edition, April 2017. Global StandardsBlowout
An uncontrolled flow of well fluids and/or formation fluids from the wellbore or into lower pressured subsurface zones (underground blowout). Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global Standards Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global StandardsBlowout
A blowout, surface or underwater, is an uncontrolled flow of gas, oil or other well fluids into the atmosphere or between the sea floor and the water surface. A blowout occurs when formation pressure exceeds the pressure applied to it by the column of drilling or other fluids in the wellbore. Source: API RP 75, Recommended Practice for Development of a Safety and Environmental Management Program for Offshore Operations and Facilities: Upstream Segment, Third Edition, May 2004. Global StandardsBlowout
Point in time at which nitrogen flows through the sample in a fluid loss test. Source: API RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005 (Reaffirmed: July 2010). Global StandardsBlowout
An uncontrolled flow of well fluids from the wellbore. Source: API RP 16Q, Recommended Practice for Design, Selection, Operation and Maintenance of Marine Drilling Riser Systems, First Edition, November 1993 (Reaffirmed August 2001). Global StandardsBlowout
An uncontrolled flow of well fluids and/or formation fluids from the well bore. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBlowout
“Blowout” means the unintentional and uncontrolled escape of oil or gas, as from a drilling well when high formation pressure is encountered (éruption). Source: Canada Oil and Gas Drilling and Production Regulations, C.R.C., c. 1517, February 2013. RegulationsBlowout
‘Blowout’ means an uncontrolled flow of well fluids and / or formation fluids from the well bore. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceBlowout
A condition when hydrocarbon containment of a wellbore is lost. Oil and gas 'blow wild' at the surface. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsBlowout
Uncontrolled flow of well fluids from the wellbore. Source: ISO 13624-1:2009, Petroleum and natural gas industries – Drilling and production equipment – Part 1:Design and operation of marine drilling riser equipment. Global StandardsBlow-out
An uncontrolled escape of reservoir fluid. 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 GuidelinesBlow-out
An uncontrolled discharge of gas, liquid, or mixture of gases and liquids from a well to the atmosphere. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsBlowout
“Blowout” means an uncontrolled flow of gas, oil, or other well fluids. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsBlowout
An uncontrolled flow of well fluids and/or formation fluids from the wellbore or into lower pressured subsurface zones (underground blowout). Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global StandardsBoard
Definition(s)
Board
“Board” means the National Energy Board established by section 3 of the National Energy Board Act (Office). Source: Canada Oil and Gas Drilling and Production Regulations, SOR/2009-315, February 2013. Regulations Source: National Energy Board Act, R.S.C., 1985, c. N-7, Canada, current to April 29, 2013. LegislationBoard
“Board” means the Canada-Nova Scotia Offshore Petroleum Board established by the joint operation of section 9 of this Act and section 9 of the Provincial Act; Office. Source: Canada-Nova Scotia Offshore Petroleum Resources Accord Implementation Act, S.C. 1988, c. 28, Canada, current to May 26, 2013. LegislationBoard
The National Energy Board, Canada-Newfoundland and Labrador Offshore Petroleum Board or the Canada-Nova Scotia Offshore Petroleum Board, as the case may be. Source: Environmental Protection Plan Guidelines, The Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada-Nova Scotia Offshore Petroleum Board, and National Energy Board, Canada, March 31, 2011. Regulatory Guidance Source: Safety Plan Guidelines, The Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada-Nova Scotia Offshore Petroleum Board, and National Energy Board, Canada, March 31, 2011. Regulatory GuidanceBoard
A body of elected or appointed individuals who jointly govern the activities of the company. The board is normally the highest authority for management of the company. The authority is conferred on the board by the shareholders or owners of the company who set articles constituting the responsibilities, rules and limitations within which the board operates. Source: IOGP Report No. 510, Operating Management System Framework for controlling risk and delivering high performance in the oil and gas industry, International Association of Oil & Gas Producers, June 2014. Global StandardsBoard
“Board” means the Canada-Nova Scotia Offshore Petroleum Board. Source: Nova Scotia Offshore Petroleum Occupational Health & Safety Requirements, Canada-Nova Scotia Offshore Petroleum Board, Canada, December 2000. RegulationsBoard
“Board” means the Environmental Studies Management Board established by subsection 78(1); Conseil. Source: Offshore Petroleum and Greenhouse Gas Storage Act 2006, Australia, amended 2012. LegislationBoard
Board means the National Offshore Petroleum Safety and Environmental Management Authority Board continued in existence by section 653. Source: Offshore Petroleum and Greenhouse Gas Storage Act 2006, Australia, amended 2012. LegislationBoard
"Board" means the Oil Industry Development Board established under section 3. Source: The Petroleum and Natural Gas Regulatory Board Act, 2006, No. 19 of 2006, India, amended as of May 2013. LegislationBoards
Definition(s)
Boards
The Canada-Newfoundland and Labrador Offshore Petroleum Board and the Canada Nova Scotia Offshore Petroleum Board. Incident Reporting and Investigation Guidelines, The Canada-Nova Scotia Offshore Petroleum Board and Canada-Newfoundland and Labrador Offshore Petroleum Board, Canada, November 30, 2012. Regulatory GuidanceBorehole Operation
Definition(s)
Borehole Operation
A borehole operation is any operation or activity at a borehole site, associated with the following. Source: A Guide to the Borehole Sites and Operations Regulations 1995, Guidance on Regulations (UK HSE L72), Second Edition, 2008. Regulatory GuidanceBorehole Operation
Any reference in these Regulations to a borehole operation is a reference to an activity or operation in the course or furtherance of, or in connection with the cessation of—- the extraction of minerals by a borehole;
- prospecting with a view to such extraction; or
- prospecting by a borehole, other than a borehole drilled from within the underground workings of a mine which is in use, with a view to the extraction of minerals by means other than a borehole, or to the preparation for sale, but not the processing, of extracted minerals at the place of any such activity or operation.
Borehole Site
Definition(s)
Borehole Site
A borehole site means any site at which borehole operations:- are going to be undertaken;
- are being undertaken; or
- have been undertaken and at which there is a borehole, whether partly drilled or completed, which has not been abandoned.
Borehole Site
“Borehole site” means a place at which a borehole operation—- is being or is to be undertaken; or
- has been undertaken, save where all borehole operations have ceased and all boreholes have been abandoned.