Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Choke Manifold
Definition(s)
Choke Manifold
Used to control flowing pressure from underbalance well. May be used on connections or trips to either keep production from displacing the drilling fluid (HP gas wells), or to artificially charge the annulus to avoid loading to reservoir pressure equilibrium (prolific oil wells). Source: IADC UBO / MPD Glossary, December 2011. Global StandardsChoke Manifold (Control Manifold)
The system of valves, chokes, and piping to control flows from the annulus and regulate pressures in the drill string/annulus flow system. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsChoke Manifold (Control Manifold)
"Choke manifold" means an assembly of valves, chokes, gauges, and lines used to control the rate of flow from the well when the blowout preventers are closed. Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. RegulationsCasing Seat Test
Definition(s)
Casing Seat Test
A procedure whereby the formation immediately below the casing shoe is subjected to a pressure equal to the pressure expected to be exerted later by a higher drilling fluid density or by the sum of a higher drilling fluid density and backpressure created by a kick. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsCasing Pressure
Definition(s)
Casing Pressure
See Backpressure. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsCasing Pressure
"Casing pressure" means the pressure within the casing or between the casing and tubing at the wellhead. Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. RegulationsBullheading
Definition(s)
Bullheading
A term to denote pumping into closed-in well without returns. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBroaching
Definition(s)
Broaching
Venting of fluids to the surface or to the seabed through channels external to the casing. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBroaching
Flow of fluids to the surface or to the sea bed through channels outside the casing. Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global StandardsBorehole Pressure
Definition(s)
Borehole Pressure
Total pressure exerted in the wellbore by a column of fluid and/or backpressure imposed at the surface. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards Source: IADC UBO / MPD Glossary, December 2011. Global StandardsBOPE
Definition(s)
BOPE
An abbreviation for blowout preventer equipment. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBOPE
"BOPE" means blowout prevention equipment. Source: Alaska Oil and Gas Conservation Commission, Definitions, Alaska Admin. Code tit. 20, § 25.990, December 7, 2012. RegulationsBlowout Preventer Drill
Definition(s)
Blowout Preventer Drill
A training procedure to determine that rig crews are completely familiar with correct operating practices to be followed in the use of blowout prevention equipment. A “dry run” of blowout preventive action. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBleeding
Definition(s)
Bleeding
Controlled release of fluids from a closed and pressured system in order to reduce the pressure. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBelching
Definition(s)
Belching
A slang term to denote flowing by heads. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBarite Slurry
Definition(s)
Barite Slurry
A mixture of barium sulfate, chemicals, and water of a unit density between 18 and 22 pounds per gallon (lb/gal). Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsBarite Plug
Definition(s)
Barite Plug
A settled volume of barite particles from a barite slurry placed in the well bore to seal off a pressured zone. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsDangerous Occurrence
Definition(s)
Dangerous occurrence
Dangerous occurrence has the meaning given by subregulation 2.41 (2). Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. RegulationsDangerous occurence
For the definition of dangerous occurrence in clause 3 of Schedule 3 to the Act, an occurrence, at a facility, that is specified in the following table is a dangerous occurrence.- An occurrence that did not cause, but could reasonably have caused:
- the death of, or serious personal injury to, a person; or
- a member of the workforce to be incapacitated from performing work for the period mentioned in subregulation (1)
- A fire or explosion
- A collision of a marine vessel with the facility
- An uncontrolled release of hydrocarbon vapour exceeding 1 kilogram
- An uncontrolled release of petroleum liquids exceeding 80 litres
- A well kick exceeding 8 cubic metres (or 50 barrels)
- An unplanned event that required the emergency response plan to be implemented
- Damage to safety-critical equipment
- An occurrence to which items 1 to 8 do not apply that:
- results in significant damage to a pipeline (for example, reducing the capacity of the pipeline to contain petroleum or greenhouse gas substance flowing through it); or
- is likely to have a result of a kind mentioned in paragraph (a); or
- is of a kind that a reasonable pipeline licensee would consider to require immediate investigation
- Any other occurrence of a kind that a reasonable operator would consider to require an immediate investigation.
Dangerous occurence
Dangerous occurrence means an occurrence declared by the regulations to be a dangerous occurrence for the purposes of this definition. Source: Offshore Petroleum and Greenhouse Gas Storage Act 2006, Australia, amended 2012. LegislationDangerous occurence
In this regulation, dangerous occurrence means any of the following events that arose out of or in connection with petroleum operations: (a) an event that did not cause, but might reasonably have caused, a major accident: (b) a well kick that either— (i) exceeded 8 cubic metres (or 50 barrels); or (ii) required the well to be shut-in: (c) an uncontrolled release of hydrocarbon vapour exceeding 1 kilogram: (d) an uncontrolled release of petroleum liquids exceeding 80 litres: (e) the failure of any part of a well whose failure would cause or contribute to, or whose purpose is to prevent or limit the effect of, the unintentional release of fluids from a well or a reservoir being drawn on by a well: (f) damage to, or failure of, a safety-critical element that required intervention to ensure it will operate as designed: (g) a fire or explosion at an installation: (h) the uncontrolled or unintentional release or escape of any substance (other than petroleum) on or from an installation, where that release or escape had the potential to cause death or serious harm to any person: (i) an unintended collapse of— (i) an installation; or (ii) any part of an installation; or (iii) any plant on an installation, where that collapse jeopardised, or could have jeopardised, the integrity of the installation: (j) subsidence or local collapse of the seabed or ground that could have affected the foundations, or the integrity, of an installation: (k) an unplanned event (other than a false alarm) that required the emergency response plan to be implemented: (l) damage to an installation, caused by adverse weather conditions, earthquakes, or other natural events, that had the potential to cause death or serious harm of any person: (m) a collision between a vessel, aircraft, or vehicle and an installation that resulted in damage to the installation, the vessel, the aircraft, or the vehicle: (n) a failure of equipment required to maintain a floating offshore installation on station: (o) an incident involving loss of stability or buoyancy of a floating offshore installation. Source: Health and Safety in Employment (Petroleum Exploration and Extraction) Regulations 2013, SR 2013/208, New Zealand, as of May 2013. RegulationsSafety Case
Definition(s)
Safety case
Safety case means the document known as a safety case that is submitted to NOPSEMA under Part 2 of Chapter 2. Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. RegulationsSafety cases
For S.I. 1996/913, in regulation 2(1) (interpretation) in the definition of “safety cases” for the words “1992” substitute “2005”. Source: The Offshore Installations (Safety Case) Regulations 2005, UK S.I. 2005/3117, 2005. RegulationsSafety cases
Explanatory Note: A safety case is defined in the Regulations as a document containing specified information relating to the management of health and safety and the control of major accident hazards and containing the particulars specified in the Schedule referred to in the provision of the Regulations under which it is prepared (regulations 2(2) and 12). Source: The Offshore Installations (Safety Case) Regulations 2005, UK S.I. 2005/3117, 2005. RegulationsDiving
Definition(s)
Diving
Diving has the meaning given by regulation 4.1. Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. RegulationsDiving
Diving:- For these Regulations, a person is diving if he or she:
- is in a chamber inside which the ambient pressure is equal to or higher than the hydrostatic pressure at a depth of 1 metre in seawater (whether or not the chamber is submerged in water or another liquid); or
- is submerged in water or another liquid and his or her lungs are subjected to a pressure greater than atmospheric pressure (whether or not he or she is wearing a wetsuit or other protective clothing); or
- is in a manned submersible craft that is submerged in water or another liquid.
- For these Regulations, diving also includes diving using a snorkel and diving without the use of any breathing apparatus.
- For these Regulations, diving does not include:
- diving using a snorkel for the purpose of conducting an environmental survey; or
- diving without the use of any breathing apparatus for that purpose.
Diving
Means diving under water where the diver breathes gases at greater than atmospheric pressure; and “diver” has a corresponding meaning. Source: Guidelines for Occupational Diving 2004, Occupational Safety and Health Service, New Zealand, updated October 2010. Regulatory GuidanceWorkforce
Definition(s)
Workforce
A collective term for the human resources of the company, including all employees and contractors, and all managers and workers. 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 StandardsWorkforce
Members of the workforce includes members of the workforce who are:- identifiable before the safety case is developed; and
- working, or likely to be working, on the relevant facility.
Workforce
“Workforce” includes every person who is for the time being working on or from an offshore installation under a contract of service or a contract for services, other than the installation manager, a body corporate or an unincorporated body of persons. Source: The Offshore Installations (Safety Representatives and Safety Committees) Regulations 1989, UK S.I. 1989/971, 1989. RegulationsIn Situ
Definition(s)
In situ
In situ means:- in relation to a facility that contains asbestos — that the asbestos was fixed or installed in the facility:
- before 1 January 2005; and
- in such a way that the asbestos does not constitute a risk to any person unless the asbestos is disturbed; and
- in relation to an item of plant — that the asbestos was fixed or installed in the item of plant:
- before 1 January 2005; and
- in such a way that the asbestos does not constitute a risk to any person unless the asbestos is disturbed.
In situ
Sampling directly within an exhaust gas stream. Source: Resolution MEPC.184(59), 2009 Guidelines for exhaust gas cleaning systems, 17 July 2009, International Maritime Organization. Regulatory GuidanceBona Fide Research
Definition(s)
Bona fide research
Bona fide research means a systematic, investigative or experimental activity conducted for the purpose of:- acquiring new knowledge; or
- creating new or improved materials, products, devices, processes or services; or
- analysis to identify the kind or quantities of ingredients in a substance.
Start-up Notice
Definition(s)
Start-up notice
Start-up notice, for a diving project, means a written notice, signed by or for the person giving it, dated and containing the following information:- the name, address and telephone number of the diving contractor for the project;
- the name, address and telephone number of a person who can be contacted by NOPSEMA at any time during the project;
- the date when diving is expected to begin;
- the expected duration of the project;
- the location of the project;
- the depth to which divers will dive;
- the purpose of the diving project;
- the estimated number of people to be engaged in the project;
- the breathing mixture to be used;
- the title, document number and revision number of the diving project plan for the project.