G

G

Definition(s)

g

Acceleration of gravity.

Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global Standards

G

Soil shear modulus.

Source: ABS Guidance Notes on Geotechnical Performance of Spudcan Foundations, January 2017. Global Standards

G&A

G&A

Definition(s)

G&A

Guide and assist. Source: Deepwater Well Control Guidelines. IADC Guidelines
GA

GA

Definition(s)

GA

General arrangement. Source: API SPEC 17J, Specification for Unbonded Flexible Pipe, Third Edition, July 2008. Global Standards    
Gage And Test Port Connections

Gage And Test Port Connections

Definition(s)

Gage And Test Port Connections

Holes drilled and tapped into API Spec equipment through which internal pressure may be measured or through which pressure may be applied to test the sealing mechanism. Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global Standards
Gage Joint

Gage Joint

Definition(s)

Gage Joint

The heaviest wall casing in the well usually located just beneath the preventers or tree.. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Gain

Gain

Definition(s)

Gain

Sensitivity adjustment produced by an amplifier or circuit. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global Standards  
Gall

Gall

Definition(s)

Gall

Surface damage on threads and seals caused by localized friction. Source: API RP 7G-2, Recommended Practice for Inspection and Classification of Used Drill Stem Elements, First Edition, August 2009. Global Standards  
Galling

Galling

Definition(s)

Galling

Cold welding of contacting material surfaces followed by tearing of the metal during further sliding/rotation. NOTE 1 Galling results from the sliding of metallic surfaces that are under high bearing forces. Galling can generally be attributed to insufficient lubrication between the mating surfaces. The purpose of the lubricating medium is to minimize metal-to-metal contact and allow efficient sliding of the surfaces. Other ways to prevent galling are to reduce the bearing forces or reduce the sliding distance. NOTE 2 There are several degrees of galling used for repair and reporting purposes as defined in 3.1.5.1 to 3.1.5.3. Source: API RP 5C5, Recommended Practice on Procedures for Testing Casing and Tubing Connections, Third Edition, July 2003 (Reaffirmed August 2010). Global Standards

Galling

Gradual removal of material from a surface due to repetitive relative motion with an adjacent surface. Source: API RP 17L2, Recommended Practice for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global Standards  

Galling

Cold welding of contacting material surfaces followed by tearing of the materials during further sliding/rotation. NOTE Galling results from the sliding of metallic surfaces that are under high bearing forces. Galling can generally be attributed to inadequate lubrication between the surfaces. The purpose of the lubrication medium is to minimize the metal-to-metal contact and allow efficient sliding of the surfaces. Other ways to prevent galling are to reduce the bearing forces or reduce the sliding distance. Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards  

Galling

Cold welding of contacting material surfaces followed by tearing of the materials during further sliding/rotation. NOTE Galling results from the sliding of metallic surfaces that are under high bearing forces. Galling can generally be attributed to insufficient lubrication between the surfaces. The purpose of the lubrication medium is to minimize the metal-to-metal contact and allow efficient sliding of the surfaces. Other ways to prevent galling are to reduce the bearing forces or reduce the sliding distance. Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards
Galvanic Isolation

Galvanic Isolation

Definition(s)

Galvanic Isolation

Arrangement within an item of intrinsically safe apparatus or associated apparatus which permits the transfer of signals or power between two circuits without any direct electrical connection between the two. Source: IEC 60079-14:2013, Explosive atmospheres – Part 14: Electrical installations design, selection and erection, Edition 5.0, November 2013. Global Standards
Game Theory

Game Theory

Definition(s)

Game Theory

Branch of applied mathematics that models interactions among agents where an agent’s choice and subsequent success depend on the choices of other agents that are simultaneously acting to maximize their own results or minimize their losses. Sample Usage: Analysts used game theory to model terrorist behavior in response to potential security measures. Annotation:
  1. Game theory can be used in the context of risk analysis to model strategic decisions and interactions of agents with conflicting interests to predict likely decision outcomes.
  2. A basic application of game theory involves two players and two strategy alternatives.
Source: DHS Risk Lexicon, U.S. Department of Homeland Security, 2010 Edition. September 2010 Regulatory Guidance
Gamma-Ray

Gamma-Ray

Definition(s)

Gamma-Ray

High-energy, short wavelength, electromagnetic radiation emitted by a nucleus, which is penetrating and is best attenuated by dense material like lead or tungsten. NOTE The energy of gamma-rays is usually between 0,010 MeV and 10 MeV. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global Standards  
Gangway (assembly)

Gangway (assembly)

Definition(s)

Gangway (assembly)

System intended to transfer personnel and cargo between 2 offshore vessels, typically including a bridge and a pedestal.

Source: Offshore Gangways, DNVGL-ST-0358, DNV GL, September 2017. Global Standards
Gangway Axis

Gangway Axis

Definition(s)

Gangway Axis

  • X axis: principal axis oriented along the length of the gangway.
  • Y axis: secondary axis, perpendicular to X axis, oriented across the length of the gangway and in the floor/walkway plane.
  • Z axis: secondary axis, perpendicular to the plane defined by X and Y axis.
Source: Offshore Gangways, DNVGL-ST-0358, DNV GL, September 2017. Global Standards
Gantry

Gantry

Definition(s)

Gantry (also known as A-Frame or Mast)

A structural frame, extending above the upper-structure to which the boom support ropes are reeved. Source: API RP 2D, Operation and Maintenance of Offshore Cranes, Sixth Edition, May 2007. Global Standards  

Gantry (also known as A-Frame or Mast)

A structural frame, extending above the machinery deck or upper-structure to which the boom support ropes are reeved. Source: API RP 2D, Operation and Maintenance of Offshore Cranes, Seventh Edition, December 2014. Global Standards  
Garbage

Garbage

Definition(s)

Garbage

Garbage means all kinds of food wastes, domestic wastes and operational wastes, all plastics, cargo residues, cooking oil, fishing gear, and animal carcasses generated during the normal operation of the ship and liable to be disposed of continuously or periodically except those substances which are defined or listed in other Annexes to the present Convention. Garbage does not include fresh fish and parts thereof generated as a result of fishing activities undertaken during the voyage, or as a result of aquaculture activities which involve the transport of fish including shellfish for placement in the aquaculture facility and the transport of harvested fish including shellfish from such facilities to shore for processing. Source: Resolution MEPC.201(62), amendments to the Annex of the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships, 1973 (Revised MARPOL Annex V), 15 July 2011, International Maritime Organization. Legislation
Gas

Gas

Definition(s)

Gas

“Gas” means natural gas and includes all substances, other than oil, that are produced in association with natural gas. Source: Canada Oil and Gas Operations Act, R.S.C., 1985, c. O-7, Canada, current to April 29, 2013. Legislation Source:  Canada Petroleum Resources Act, R.S.C. 1985, c. 36 (2nd Supp.), current to April 29, 2013. Legislation 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 Guidance  

Gas

“Gas” means natural gas and includes all substances, other than oil, that are produced in association with natural gas, but does not include coal-bed methane associated with the development or operation of a coal mine; gaz. Source: Canada-Nova Scotia Offshore Petroleum Resources Accord Implementation Act, S.C. 1988, c. 28, Canada, current to May 26, 2013. Legislation

Gas

"Gas" means and includes all natural gas and all other fluid hydrocarbons not hereinbelow defined as oil. Source: Control of Oil and Gas Resources, North Dakota Century Code, Title 38, Chapter 8, February 2013. Legislation  

Gas

"Gas" means any petroleum hydrocarbon existing in the gaseous phase.
  1. Casinghead gas means any gas or vapor, or both, indigenous to an oil stratum and produced from such stratum with oil.
  2. Dry gas or dry natural gas means any gas produced in which there are no appreciable hydrocarbon liquids recoverable by separation at the wellhead.
  3. Condensate gas means any gas which is produced with condensate as defined as "condensate".
Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. Regulations  

Gas

A fluid, such as air, that has neither independent shape nor volume, but tends to expand indefinitely. Source: CPetroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. Regulations  

Gas

“Gas” means all natural gas and all other fluid hydrocarbons not defined below as oil, including condensate. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. Regulations  

Gas

State of matter that has no definite shape or volume. Source: IADC UBO / MPD Glossary, December 2011. Global Standards  

Gas

“Gas” means all natural gas and all other fluid hydrocarbons not defined below as oil, including condensate. Source: National Energy Board Act, R.S.C., 1985, c. N-7, Canada, current to April 29, 2013. Legislation  

Gas

Person, Producer, Gas, and Products―shall have the meaning prescribed for each of said words as defined in R.S. 30:3. Source: Natural Resources, Office of Conservation – General Operations, Louisiana Administrative Code, Title 43, Part XIX, March 2013. Regulations  

Gas

The words POOL, PERSON, OWNER, PRODUCER, OIL, GAS, WASTE, CORRELATIVE RIGHTS and COMMON SOURCE OF SUPPLY are defined by the Act, and said definitions are hereby adopted in these Rules and Regulations. From C.R.S. 34-60-103 (2012): "Gas" means all natural gases and all hydrocarbons not defined in this section as oil. Source: Oil and Gas Conservation Commission, Practice and Procedure, Code of Colorado Regulations, 2 CCR 404-1, February 2013. Regulations  

Gas

“Gas”, also known as natural gas, means a combustible vapor composed chiefly of hydrocarbons occurring naturally in a pool the division has classified as a gas pool. Source: Oil and Gas, New Mexico Administrative Code Title 19, Chapter 15, January 2013. Regulations  

Gas

“Gas” means any substance which is gaseous at a temperature of 15°C and a pressure of 101.325 kPa (1013.25 mb). For the purposes of paragraphs (2) and (4), references to gas include any substance which consists wholly or mainly of gas. Source: The Health and Safety at Work etc. Act 1974 (Application outside Great Britain) Order 2001, UK S.I. 2013/214, 2013. Regulations  

Gas

In this section “gas” means any substance which is or (if it were in a gaseous state) would be gas within the meaning of Part I of the Gas Act 1986. Source: UK Offshore Safety Act 1992, 1992 c. 15 (February 2013). Legislation  
Gas Allowable Or Allowable Gas

Gas Allowable Or Allowable Gas

Definition(s)

Gas Allowable Or Allowable Gas

"Gas allowable" or "allowable gas" means the amount of natural gas authorized to be produced from any well by order of the Commission or as provided by statute. Source: Corporation Commission, Oil and Gas Conservation, Oklahoma Administrative Code 165:10, February 2013. Regulations
Gas Analysis

Gas Analysis

Definition(s)

Gas Analysis

Gas analysis unit is the assembly in which the detector is housed, along with any associated analysis components. Source: IMO MSC.1/Circ.1343, amendments to the International Aeronautical and Maritime Search and Rescue (IAMSAR) Manual, 24 May 2010, International Maritime Organization. Regulatory Guidance Source: IMO MSC.1/Circ.1370, Guidelines for the design, construction and testing of fixed hydrocarbon gas detection systems, 22 June 2010, International Maritime Organization. Regulatory Guidance  
Gas Buster

Gas Buster

Definition(s)

Gas Buster

A slang term to denote a mud: gas separator. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards  

Gas Buster

Slang for mud / gas separator. Source: IADC UBO / MPD Glossary, December 2011. Global Standards  
Gas Concentration

Gas Concentration

Definition(s)

Gas Concentration

Gas concentration is the amount of gas or vapour being measured, as expressed in % LFL. Source: IMO MSC.1/Circ.1343, amendments to the International Aeronautical and Maritime Search and Rescue (IAMSAR) Manual, 24 May 2010, International Maritime Organization. Regulatory Guidance Source: IMO MSC.1/Circ.1370, Guidelines for the design, construction and testing of fixed hydrocarbon gas detection systems, 22 June 2010, International Maritime Organization. Regulatory Guidance  
Gas Cut

Gas Cut

Definition(s)

Gas Cut

Gas entrained in a drilling fluid. Source: IADC UBO / MPD Glossary, December 2011. Global Standards
Gas Cut Drilling Fluid

Gas Cut Drilling Fluid

Definition(s)

Gas Cut Drilling Fluid

Drilling Fluid that has become entrained with gas from previously drilled gas bearing formation which in turn lowers the drilling fluid density and hydrostatic head of the drilling fluid column. Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global Standards  
Gas Detection Alarm

Gas Detection Alarm

Definition(s)

Gas Detection Alarm

An alarm which indicates that gas has been detected. Source: IMO resolution A.1021(26), Code on Alarms and Indicators, 2009, 18 January 2010, International Maritime Organization. Regulatory Guidance
Gas Detection Instrument

Gas Detection Instrument

Definition(s)

Gas detection instrument

An assembly of electrical, mechanical, and chemical components designed to sense and respond continuously to the presence of chemical gases in atmospheric mixtures. Source: API RP 49, Recommended Practice for Drilling and Well Servicing Operations Involving Hydrogen Sulfide, Third Edition, May 2001. Global Standards
Gas Drilling

Gas Drilling

Definition(s)

Gas Drilling

See Aerated Fluid. Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global Standards  
Gas Explosions

Gas Explosions

Definition(s)

Gas Explosions

Gas explosions can be defined as the combustion of a premixed gas cloud containing fuel and an oxidizer that can result in a rapid rise in pressure. Source: API RP 2FB, Recommended Practice for the Design of Offshore Facilities Against Fire and Blast Loading, First Edition, April 2006. Global Standards  

Gas Explosions

Combustion of a flammable gas or mist which generates blast waves due to confinement of the combustion induced flow or the acceleration of the flame front by obstacles in the flame path Source: ISO 13702:2015, Petroleum and natural gas industries — Control and mitigation of fires and explosions on offshore production installations — Requirements and guidelines, Second Edition, August 2015. Global Standards
Gas Facility

Gas Facility

Definition(s)

Gas Facility

GAS FACILITY shall mean those facilities that process or compress natural gas after production-related activities which are conducted at or near the wellhead and prior to a point where the gas is transferred to a carrier for transport. Source: Oil and Gas Conservation Commission, Practice and Procedure, Code of Colorado Regulations, 2 CCR 404-1, February 2013. Regulations  
Gas Free or Free of Gas

Gas Free or Free of Gas

Definition(s)

Gas Free or Free of Gas

Free from harmful or hazardous concentrations of vapors, fumes and gases. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. Regulations
Gas Gatherer

Gas Gatherer

Definition(s)

Gas Gatherer

Gas Gatherer―anyone who gathers gas other than his own in a field or from several fields for delivery to a transporter or gas processing plant. Source: Natural Resources, Office of Conservation – General Operations, Louisiana Administrative Code, Title 43, Part XIX, March 2013. Regulations  
Gas Group

Gas Group

Definition(s)

Gas Groups (division classification method)

For purposes of testing, approval, and area classification, various air mixtures (not oxygen enriched) are grouped as shown below. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Group A

Atmospheres that do or may contain acetylene. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Group B

Atmospheres that do or may contain hydrogen, or other substances specified by NFPA 497. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Group C

Atmospheres that do or may contain hydrogen sulfide (H2S), or other substances specified by NFPA 497. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Group D

Atmospheres that do or may contain natural gas, hydrocarbons or other substances specified by NFPA 497. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Gas, Group I

A term used by ANSI/ISA S12.24.01 (IEC 60079-10 MOD) to describe atmospheres containing firedamp (a mixture of gases, composed mostly of methane, found underground, usually in mines). Since this RP does not apply to installations underground in mines, this term is not used further. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Gas, Group II

The group used to describe gases found aboveground and subdivided into IIC, IIB, and IIA, as noted below, according to the nature of the gas or vapor, for protection techniques "d," "ia," and "ib" and, where applicable, "n" and "o." Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Gas, Group IIA

Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or flammable gas, flammable liquid produced vapor, or combustible liquid produced vapor mixed with air that may burn or explode having either a maximum experimental safe gap (MESG) value greater than 0.90 mm or a minimum igniting current ratio (MIC ratio) greater than 0.80, see NFPA 497. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Gas, Group IIB

Atmospheres containing acetaldehyde, ethylene, or flammable gas, flammable liquid produced vapor, or combustible liquid produced vapor mixed with air that may burn or explode having either a MESG value greater than 0.50 mm and less than or equal to 0.90 mm or a MIC ratio greater than 0.45 and less than or equal to 0.80, see NFPA 497. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards  

Gas, Group IIC

Atmospheres containing acetylene, hydrogen, or flammable gas, flammable liquid produced vapor, or combustible liquid produced vapor mixed with air that may burn or explode, having either a MESG value less than or equal to 0.50 mm or a MIC ratio less than or equal to 0.45, see NFPA 497. Source: API Recommended Practice 14FZ, Recommended Practice for Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations, Second Edition, May 2013. Global Standards Source: API RP 14F, Design, Installation, and Maintenance of Electrical Systems for Fixed and Floating Offshore Petroleum Facilities for Unclassified and Class 1, Division 1 and Division 2 Locations, Fifth Edition, July 2008. Global Standards