Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Freezing Operation
Definition(s)
Freezing operation
Creation of a plug by freezing a liquid in a pipe or fitting to confine the pressure while removing defective or inadequate equipment downstream of the plug. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsFreezing operation
“Freezing operation” means the creation of a plug by freezing a liquid slug in a pipe fitting. [Mich. Admin. Code R 408 (2013)]. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsElevator
Definition(s)
Elevators
A mechanical device attached to the traveling block that latches around and supports the pipe during hoisting or lowering operations. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsElevator
“Elevator” means a mechanical device attached to the traveling block that latches around and supports the pipe during hoisting. [Mich. Admin. Code R 408 (2013)]. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsElevator
A metal mechanical device used in connection with and suspended from a traveling block or hoisting line, to hold pipe or sucker rods in suspension when being hoisted or lowered in a well. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsConductor Pipe
Definition(s)
Conductor pipe
A relatively short string of large diameter pipe which is installed to keep the top of the hole open and provide a means of returning the drilling fluid from the wellbore to the surface drilling fluid system until the first casing string is set in the well. Conductor pipe may also be used in well control when drilling to surface casing depth. Conductor pipe may or may not be cemented. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsConductor pipe
A relatively short string of large diameter pipe that is set to keep the top of the hole open and provide a means of returning the upflowing drilling fluid from the wellbore to the surface drilling fluid system until the first casing string is set in the well. Conductor pipe may also be used in well control. Conductor pipe is usually cemented. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsConductor pipe
A relatively short string of large diameter pipe that is set to keep the top of the hole open and provide a means of returning the up flowing drilling fluid from the wellbore to the surface drilling fluid system until the first casing string is set in the well. Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global StandardsConductor pipe
“Conductor pipe” means steel casing, either driven or set through the soil, and/or unconsolidated rock materials and into bedrock for the purpose of isolating near surface water, and such unconsolidated rock materials from the well bore. Source: Division of Mineral Resources Management - Oil and Gas, Ohio Administrative Code, Chapter 1501:9, January 2012. RegulationsConductor pipe
Conductor pipe—A short string of large-diameter casing used to stabilize the top of the wellbore in shallow unconsolidated formations. Source: Oil and Gas Wells, Pennsylvania Code, Title 25, Chapter 78, December 2012. RegulationsCombustible Liquid
Definition(s)
Combustible Liquid (Class II, IIIA, and IIIB Liquids)
A liquid having a flash point at or above 100°F (37.80°C). Combustible liquids are subdivided as follows: Class II liquids, those having flash points at or above l00°F (37.8°C) and below 140°F (60°C). Class IIA liquids, those having flash points at or above 140°F (60°C) and below 200°F (93°C). Class IIIB liquids, those having flash points at or above 200°F (93°C). (See NFPA 30.) Source: API RP 14G, Recommended Practice for Fire Prevention and Control on Fixed Open-type Offshore Production Platforms: Upstream Segment, Fourth Edition, April 2007. Global StandardsCombustible Liquid
Any liquid having a flashpoint at or above 100 °F (37.8 °C). Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsCombustible Liquid
Any liquid having a flash-point at or above 100 °F. Source: API RP 74, Recommended Practice for Occupational Safety for Onshore Oil and Gas Production Operation, First Edition, October 2001 (March 2007). Global StandardsCombustible Liquid
Any material which has a fluidity greater than that of 300 penetration asphalt when tested in accordance with American Society For Testing and Materials. Designation D5-86, Standard Test Method For Penetration of Bituminous Materials, pages 1-5, which is hereby incorporated by reference. Combustible liquids shall be subdivided as follows: Class II liquids shall include those having flash points at or above 100oF (37.8oC) and below 140oF (60oC). Class IIIA liquids include those having flash points at or above 140oF (60oC) and below 200oF (93.4oC). Class IIIB liquids shall include those having flash points at or above 200oF (93.4oC). Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsChristmas Tree
Definition(s)
Christmas tree
An assembly of valves, fittings, chokes, and gauges used in monitoring and controlling producing, injection, and inactive wells. The Christmas tree is assembled at the top of the well starting with the uppermost flange of the tubing head. Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global StandardsChristmas tree
The valves and fittings assembled at the top of a completed well to control the flow of hydrocarbons and other fluids. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsChristmas tree
The valves and fittings assembled at the top of a completed well to control the flow of hydrocarbons and other fluids. See API Spec 6A. Source: API RP 74, Recommended Practice for Occupational Safety for Onshore Oil and Gas Production Operation, First Edition, October 2001 (March 2007). Global StandardsChristmas tree
Assembly of equipment, including tubing-head adapters, valves, tees, crosses, top connectors and chokes attached to the uppermost connection of the tubing head, used to control well production. Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsChristmas tree
The collection of fittings and valves, on the top of the casing, controlling the hydrocarbon production rate. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsChristmas tree
“Christmas tree” means the valves and fittings assembled at the top of a completed well to control the flow of hydrocarbons and other fluids. [Mich. Admin. Code R 408 (2013)]. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsCementing
Definition(s)
Cementing
Making cement into a slurry and pumping it into a wellbore to perform functions such as supporting casing, isolating formations behind casing, protecting fresh water sands, and sealing perforations in casing. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsCementing
“Cementing” means the act of pumping a slurry into a wellbore to perform functions such as supporting and sealing casing, isolating formation behind casing, protecting freshwater formations, and sealing perforations in casing. [Mich. Admin. Code R 408 (2013)]. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsCellar
Definition(s)
Cellar
Excavation around the wellhead to provide space for items of equipment at the top of the wellbore. 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 RP 74, Recommended Practice for Occupational Safety for Onshore Oil and Gas Production Operation, First Edition, October 2001 (March 2007). Global StandardsCellar
A pit beneath the rig floor to provide additional height between the rig floor and the wellhead and to allow the installation of the bops / rotating head / rotating diverter, rat hole mouse hole etc. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsCellar
“Cellar” means an excavation around the wellhead to provide space for items of equipment at the top of the wellbore. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsCellar
An excavation around the well head to provide space for equipment at the top of the well bore. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsCatwalk
Definition(s)
Catwalk
Elongated platform adjacent to the rig floor where pipe is laid out and lifted into the derrick. The catwalk is connected to the rig floor by a pipe ramp. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsCatwalk
“Catwalk” means a elongated platform to the side of a rig where pipe is laid out and lifted into the derrick. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsCathead
Definition(s)
Catline, Cathead
Catline is a line powered by the cathead, which is a concave, rotating, pulley-type device mounted on the end of the cat shaft of the drawworks. Catlines are used to lift or pull equipment around a rig. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsCathead
“Cathead” means a rotating device mounted on the end of a shaft of the draw works. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsCathead
Unless referred to as “automatic” cathead, means a spool shaped metal mechanical device mounted on the end of a shaft on which a rope is wrapped. The rotating cathead imparts a pulling power to the rope that is wrapped on it. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsCatline
Definition(s)
Catline, cathead
Catline is a line powered by the cathead, which is a concave, rotating, pulley-type device mounted on the end of the cat shaft of the drawworks. Catlines are used to lift or pull equipment around a rig. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsCatline
A rope, usually reeved on a crown block sheave in a derrick or mast, for the primary purpose of lifting and transferring materials from one place to another about the derrick or mast floor. A rotating cathead imparts the pulling power to the catline that is wrapped on it. Source: Petroleum Safety Orders--Drilling and Production, Definitions, California Code of Regulations, 8 CCR § 6505, December 2012. RegulationsBlocks, Crown, and Traveling
Definition(s)
Blocks, Crown, and Traveling
The fixed upper and movable lower blocks, respectively, of the block and tackle assembly on a rig that raises and lowers the drill string or tubing. Source: API RP 54, Recommended Practice for Occupational Safety for Oil and Gas Well Drilling and Servicing Operations, Third Edition, August 1999 (2007). Global StandardsBlocks, Crown, and Traveling
“Blocks, crown, and traveling” means the fixed upper and movable lower blocks, respectively, of the block and tackle assembly on a rig that raises and lowers the drill string or tubing. Source: Oil and Gas Drilling and Servicing Operations, Michigan Administrative Code R 408, February 8, 2013. RegulationsShould
Definition(s)
Should
For the purposes of this publication, the term should denotes a RP a) where a safe comparable alternative practice is available; b) that may be impractical under certain circumstances; or c) that may be unnecessary under certain circumstances or applications. This word indicates that the rule is a recommendation, the advisability of which depends on the facts in each situation. Sources: API RP 2D, Operation and Maintenance of Offshore Cranes, Sixth Edition, May 2007. Global StandardsShould
As used in a standard, “should” denotes a recommendation or that which is advised but not required in order to conform to the specification. Sources: API RP 17L2, Recommended Practice for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global Standards Sources: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global StandardsShould
“Should” is used to state that a provision is not mandatory, but is recommended as good practice. Sources: API RP 17L2, Recommended Practice for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global StandardsShould
Denotes a “recommended practice(s)”- Where a safe comparable alternative practice(s) is available;
- That may be impractical under certain circumstances; or
- That may be unnecessary under certain circumstances.
Should
Denotes a recommended practice:- Where a safe comparable alternative practice is available;
- That may be impractical under certain circumstances: or
- That may be unnecessary for personnel safety under certain circumstances.
Should
Denotes a recommended practice(s) a) where a safe comparable alternative practice(s) is available; b) that may be impractical under certain circumstances; or c) that may be unnecessary under certain circumstances or applications. Sources: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global StandardsShould
As used in a standards, “should” denotes a recommendation or that which is advised but not required in order to conform to the specification. Sources: API RP 67, Recommended Practice for Oilfield Explosives Safety, Upstream Segment, Second Edition, May 2007. Global StandardsShould
For the purpose of this document, should denotes a recommended practice(s)- Where a safe comparable alternative practice(s) is available;
- That may be impractical under certain circumstances; or
- That may be unnecessary for personnel safety under certain circumstances.
Should
The term “should” denotes a recommendation or that which is advised but not required in order to conform to the recommended practice. Sources: API RP 96, Deepwater Well Design and Construction, First Edition, March 2013. Global StandardsShould
SHOULD is used to indicate that a provision is not mandatory, but RECOMMENDED as good practice. Sources: API SPEC 5CRA, Specification for Corrosion Resistant Alloy Seamless Tubes for Use as Casing, Tubing and Coupling Stock, Upstream Segment, First Edition, February 2010 (Errata August 2011). Global Standards Sources: API SPEC 5DP, Specification for Drill Pipe, First Edition, August 2009. Global StandardsShould
As used in a standard, “should” denotes a recommendation or that which is advised but not required in order to conform to the specification. Sources: API SPEC 5CRA, Specification for Corrosion Resistant Alloy Seamless Tubes for Use as Casing, Tubing and Coupling Stock, Upstream Segment, First Edition, February 2010 (Errata August 2011). Global Standards Sources: API SPEC 5CT, Specification for Casing and Tubing, Upstream Segment, Ninth Edition, July 2011 (Errata September 2012). Global Standards Sources: API SPEC 17D, Design and Operation of Subsea Production Systems—Subsea Wellhead and Tree Equipment, Upstream Segment, Second Edition May 2011 (Errata September 2011). Global StandardsShould
Should: As used in a standard, "should" denotes a recommendation or that which is advised but not required in order to conform to the specification. Sources: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global Standards Sources: API SPEC 10A, Specification for Cements and Materials for Well Cementing, Twenty-fourth Edition, December 2010. Global Standards Sources: API SPEC 11D1, Packers and Bridge Plugs, Upstream Segment, Second Edition, July 2009. Global Standards Sources: API SPEC 13A, Specification for Drilling Fluids Materials, Eighteenth Edition, February 2010. Global Standards Sources: API SPEC 17E, Specification for Subsea Umbilicals, Upstream Segment, Fourth Edition, October 2010. Global StandardsShould
Refers to a recommended method which provides an example of how an operator can meet an expectation, but does not prevent an operator from selecting alternative best practices. Source: 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 GuidanceShould
Indicates a recommendation that a certain course of action is preferred or particularly suitable. Alternative courses of action are allowable under the standard where agreed between contracting parties but shall be justified and documented. Sources: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global StandardsShould
"Should" means recommended. Sources: State of Wyoming Occupational Safety and Health Rules and Regulations for Oil and Gas Well Drilling, Revised January 8, 2013. RegulationsShould
“Should”, means the authorities' recommended way of fulfilling the functional requirement. Alternative solutions with documented corresponding functionality and quality can be used without having to present this to the authorities. Source: Guidelines Regarding the Framework Regulations, Norway, updated December 2012. Regulatory GuidanceShould
Verbal form used to indicate that among several possibilities one is recommended as particularly suitable, without mentioning or excluding others, or that a certain course of action is preferred, but not necessarily required. Source: NORSOK D-002, Well intervention equipment, Rev. 2, June 2013. Global StandardsShould
Should is a recommendation. Alternative solutions having the same functionality and quality are acceptable. Source: NORSOK D-007, Well Testing Systems, Rev. 1, January 1996. Global StandardsShould
Indicates a preferred course of action or recommended practice to be adopted. Source: Approved Code of Practice for Managing Hazards to Prevent Major Industrial Accidents, Health and Safety in Employment Act 1992, Department of Labour, New Zealand, July 1994. Regulatory GuidanceShould
verbal form used to indicate that among several possibilities one is recommended as particularly suitable, without mentioning or excluding others, or that a certain course of action is preferred but not necessarily required . Source: Rules for Classification and Construction, IV Industrial Services, 6 Offshore Technology, 9 Guideline for Personnel Transfers by Means of Lifting Appliances, Edition 2011, Germanischer Lloyd SE, Global StandardsShould
Indicates that among several possibilities, one is recommended as particularly suitable, without mentioning or excluding others, or that a certain course of action is preferred but not necessarily required. Other possibilities may be applied subject to agreement. Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsSCF
Definition(s)
SCF
"Scf" means standard cubic feet. Source: Alaska Oil and Gas Conservation Commission, Definitions, Alaska Admin. Code tit. 20, § 25.990, December 7, 2012. RegulationsSCF
Stress concentration factor. Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global Standards Source: API Standard 2RD, Dynamic Risers for Floating Production Systems, Second Edition, September 2013. Global Standards Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards Source: API SPEC 17D, Design and Operation of Subsea Production Systems—Subsea Wellhead and Tree Equipment, Upstream Segment, Second Edition May 2011 (Errata September 2011). Global Standards Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global Standards Source: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global Standards Source: Rules for Classification – Offshore units, DNVGL-OU-0101, Offshore drilling and support units, DNV GL, July 2015. Global Standards Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsSCF
Equal to the local peak stress in a component (including welds) divided by the nominal stress in the component cross-section at the location of the local peak stress
Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global StandardsSCF
Standard cubic feet. Source: API RP 49, Recommended Practice for Drilling and Well Servicing Operations Involving Hydrogen Sulfide, Third Edition, May 2001. Global StandardsSCF
Local peak alternating stress in a component (including welds) divided by the nominal alternating stress in the pipe wall at the location of the component.- NOTE: This factor is used to account for the increase in the stresses caused by geometric stress amplifiers that occur in the riser component.
SCF
Factor relating a nominal stress to the local stress at a detail. NOTE Adapted from ISO 19902:2007, definition 3.50. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global StandardsRCRA
Definition(s)
RCRA
Resource Conservation & Recovery Act. Source: API RP 49, Recommended Practice for Drilling and Well Servicing Operations Involving Hydrogen Sulfide, Third Edition, May 2001. Global StandardsRCRA
“RCRA” means the federal Resource Recovery and Conservation Act. Source: Oil and Gas, New Mexico Administrative Code Title 19, Chapter 15, January 2013. RegulationsPPM
Definition(s)
PPM
"Ppm" means parts per million. Source: Alaska Oil and Gas Conservation Commission, Definitions, Alaska Admin. Code tit. 20, § 25.990, December 7, 2012. Regulations Source: API RP 49, Recommended Practice for Drilling and Well Servicing Operations Involving Hydrogen Sulfide, Third Edition, May 2001. Global Standards Source: Oil and Gas, New Mexico Administrative Code Title 19, Chapter 15, January 2013. RegulationsPPM
PPM means ml/m3. <Annex II, Chapter 1, Regulation 1>. Source: Resolution MEPC.118(52), amendments to the Annex of the Protocol of 1978 relating to the International Convention for the Prevention of Pollution from Ships, 1973 (Revised Annex II of MARPOL 73/78), 15 October 2004, International Maritime Organization. LegislationCFR
Definition(s)
CFR
Code of Federal Regulations. Source: API RP 49, Recommended Practice for Drilling and Well Servicing Operations Involving Hydrogen Sulfide, Third Edition, May 2001. Global Standards Source: API RP 14G, Recommended Practice for Fire Prevention and Control on Fixed Open-type Offshore Production Platforms: Upstream Segment, Fourth Edition, April 2007. Global Standards Source: API RP 98, Personal Protective Equipment Selection for Oil Spill Responders, First Edition, August 2013. Global Standards Source: API RP 2SIM, Structural Integrity Management of Fixed Offshore Structures, First Edition, November 2014. Global Standards Source: Oil and Gas Division, Texas Administrative Code, Title 16, Chapter 3, February 2013. RegulationsZone
Definition(s)
Zone
A method of specifying the probability that a location is made hazardous by the presence, or potential presence, of flammable concentrations of gases and vapors, or combustible mixtures of dusts. 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 StandardsZone 0 (IEC)
An area in which an explosive gas atmosphere is present continuously or for long periods. (See IEC 60050, IEV 426-03-03.) 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 StandardsZone 0, Class I (NEC)
A Class I, Zone 0 location is a location 1) in which ignitable concentrations of flammable gases or vapors are present continuously; or 2) in which ignitable concentrations of flammable gases or vapors are present for long periods of time, see NEC Section 505.5(B)(1). 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 StandardsZone 0, Class I (NEC)
A Class I, Zone 0 location is a location 1) in which ignitable concentrations of flammable gases or vapors are present continuously; or 2) in which ignitable concentrations of flammable gases or vapors are present for long periods of time, see NEC Section 505-9(a). 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 StandardsZone 0
Place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is present continuously or for long periods or frequently.[IEV 426-03-03, modified] NOTE The MODU code definition is “Zone 0: in which an explosive gas/air mixture is continuously present or present for long periods.” Source: IEC 61892-7, Mobile and fixed offshore units – Electrical installations – Part 7: Hazardous areas. Global StandardsZone 1 (IEC)
An area in which an explosive gas atmosphere is likely to occur in normal operation, see IEC 60050, IEV 426-03-04. 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 StandardsZone 1, Class I (NEC)
A Class I, Zone 1 location is a location 1) in which ignitable concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or 2) in which ignitable concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or 3) in which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitable concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or 4) that is adjacent to a Class I, Zone 0 location from which ignitable concentrations of vapors could be communicated, unless communication is prevented by adequate positive-pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided, see NEC Article 505.5(B)(2). 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 StandardsZone 1, Class I (NEC)
A Class I, Zone 1 location is a location 1) in which ignitable concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or 2) in which ignitable concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or 3) in which equipment is operated or processes are carried on, of such a nature that equipment breakdown or faulty operations could result in the release of ignitable concentrations of flammable gases or vapors and also cause simultaneous failure of electrical equipment in a mode to cause the electrical equipment to become a source of ignition; or 4) that is adjacent to a Class I, Zone 0 location from which ignitable concentrations of vapors could be communicated, unless communication is prevented by adequate positive-pressure ventilation from a source of clean air and effective safeguards against ventilation failure are provided, see NEC Article 505-9(b). 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 StandardsZone 1
Place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally. [IEV 426-03-04, modified] NOTE The MODU code definition is “Zone 1: in which an explosive gas/air mixture is likely to occur in normal operation.” Source: IEC 61892-7, Mobile and fixed offshore units – Electrical installations – Part 7: Hazardous areas. Global StandardsZone 2 (IEC)
An area in which an explosive gas atmosphere is not likely to occur in normal operation and, if it does occur, is likely to do so only infrequently and will exist for a short period only, see IEC 60050, IEV 426-03-05. 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 StandardsZone 2, Class I (NEC)
A Class I, Zone 2 location is a location 1) in which ignitable concentrations of flammable gases or vapors are not likely to occur in normal operation, and if they do occur, will exist only for a short period; or 2) in which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used, but in which the liquids, gases, or vapors normally are confined within closed containers or closed systems from which they can escape only as a result of accidental rupture or breakdown of the containers or system, or as the result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or 3) in which ignitable concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation, but which may become hazardous as the result of failure or abnormal operation of the ventilation equipment; or 4) that is adjacent to a Class I, Zone 1 location, from which ignitable concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided, see NEC Section 505.5(B)(3). 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 StandardsZone 2, Class I (NEC)
A Class I, Zone 2 location is a location 1) in which ignitable concentrations of flammable gases or vapors are not likely to occur in normal operation, and if they do occur, will exist only for a short period; or 2) in which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used, but in which the liquids, gases, or vapors normally are confined within closed containers or closed systems from which they can escape only as a result of accidental rupture or breakdown of the containers or system, or as the result of the abnormal operation of the equipment with which the liquids or gases are handled, processed, or used; or 3) in which ignitable concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation, but which may become hazardous as the result of failure or abnormal operation of the ventilation equipment; or 4) that is adjacent to a Class I, Zone 1 location, from which ignitable concentrations of flammable gases or vapors could be communicated, unless such communication is prevented by adequate positive-pressure ventilation from a source of clean air, and effective safeguards against ventilation failure are provided, see NEC Section 505-9(c). 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 StandardsZone 2
Place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapour or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only.[IEV 426-03-05, modified] NOTE 1 In this definition, the word "persist" means the total time for which the flammable atmosphere will exist. This will normally comprise the total of the duration of the release, plus the time taken for the flammable atmosphere to disperse after the release has stopped. NOTE 2 Indications of the frequency of the occurrence and duration may be taken from codes relating to specific industries or applications. NOTE 3 The MODU code definition is “Zone 2: in which an explosive gas/air mixture is not likely to occur, or in which such a mixture, if it does occur, will only exist for a short time.”3Zone
“Zone” means any stratum or strata designated by the Minister as a zone, either generally or in respect of any designated area, or any specified well or wells (zone). Source: Canada Oil and Gas Drilling and Production Regulations, C.R.C., c. 1517, February 2013. RegulationsZone
“Zone” means any stratum or any sequence of strata and includes, for the purposes of the definition “commingled production”, section 7, subsection 61(2), sections 64 to 66 and 73, subsection 82(2) and section 85, a zone that has been designated as such by the Board under section 4 (couche). Source: Canada Oil and Gas Drilling and Production Regulations, SOR/2009-315, February 2013. Regulations 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 GuidanceZone
Part of a hazardous area based upon the frequency of the occurrence and duration of an explosive gas atmosphere. 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 StandardsZone
“Zone” means any stratum or any sequence of strata and includes, for the purposes of the definition “commingled production”, section 7, subsection 61(2), sections 64 to 66 and 74, subsection 83(2) and section 86, a zone that has been designated as such by the Board under section 4; couche. Source: Nova Scotia Offshore Petroleum Drilling and Production Regulations, SOR/2009-317, Canada, current to May 31, 2012. RegulationsZone
See “security zone
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