Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Worker
Definition(s)
Worker
person performing one or more activities to achieve a goal within a work system (2.2) [SOURCE: ISO 26800:2011, 2.11, modified — synonym “operator” omitted]. 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 StandardsWorker
person performing one or more activities to achieve a goal within a work system (2.2) [SOURCE: ISO 26800:2011, 2.11, modified — synonym “operator” omitted]. Source: ISO 6385:2016, Ergonomics principles in the design of work systems, Third Edition, September 2016. Global StandardsWorking Gauges
Definition(s)
Working Gauges
Gauges used for gauging product threads. Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global StandardsWorking Load
Definition(s)
Working Load
The external load in pounds (kilograms), applied to the crane including the weight of load-attaching equipment such as load block, shackles, and slings. NOTE The maximum allowable working load for a given condition is the safe working load (SWL). Source: API RP 2D, Operation and Maintenance of Offshore Cranes, Seventh Edition, December 2014. Global StandardsWorking Load
The external load in pounds (kilograms), applied to the crane including the weight of load-attaching equipment such as load block, shackles, and slings. The maximum allowable working load for a given condition would be the Safe Working Load (SWL). Source: API RP 2D, Operation and Maintenance of Offshore Cranes, Sixth Edition, May 2007. Global StandardsWorking Load Limit (WLL)
Definition(s)
working load limit <lifting set>
Maximum mass or weight that a lifting component is designed to sustain in lifting service.
Source: API Standard 2CCU, Offshore Cargo Carrying Units, First Edition, August 2017. Global StandardsWorking Load Limit
A load value assigned to loose gear by the manufacturer that is a fraction of the breaking load value which should not be exceeded during use of BOP handling systems and equipment. Source: API SPEC 7K, Drilling and Well Servicing Equipment Upstream Segment, Fifth Edition, June 2010 (August 2010). Global Standards Source:API SPECIFICATION 7K, Drilling and Well Servicing Equipment, Sixth Edition, December 2015. Global StandardsWorking Load Limit
Working Load Limit (WLL) of the interchangeable components refers to the permissible load of these parts (e.g. shackles, hooks, chains, links etc.) without regard to the hoist load and/or dead load coefficient. It should be noted that the Working Load Limit (WLL) of an interchangeable component is not normally identical the Safe Working Load (SWL) of the lifting appliance, as the components have to be dimensioned in accordance with the local occurring forces. These forces are indicated in the rigging plans. 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 StandardsWorking Pressure (WP)
Definition(s)
Working Pressure
The pressure to which a particular piece of equipment is subjected during normal operations. Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global StandardsWorking Pressure
Pressure to which a particular piece of equipment is subjected during normal operation. Source: API SPEC 7-1, Specification for Rotary Drill Stem Elements, First Edition, March 2006 (Addendum April 2011). Global StandardsWorking Pressure
SSSV internal pressure rating, including the differential rating with the valve closed. Source: API SPEC 14A, Specification for Subsurface Safety Valve Equipment, Eleventh Edition, October 2005 (Reaffirmed June 2012). Global StandardsWorking Pressure
The maximum pressure a component is subjected to during normal operations and applied to its design. Source: NOGEPA Industrial Guideline No. 43, Surface BOP Review, Best Practices Checklist, Netherlands, Version 0, December 2011. Global StandardsWorking Pressure Rating
Definition(s)
Working Pressure Rating
The maximum pressure at which an item is designed for safe operation. Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global StandardsWorking Spaces
Definition(s)
Working spaces
Working spaces are those open or enclosed spaces containing equipment and processes, associated with drilling operations, which are not included in hazardous areas and machinery spaces. Source: IMO Resolution A.1023(26), Code for the Construction and Equipment of Mobile Offshore Drilling Units (2009 MODU Code), 2009. Global Standards Source: Rules and Regulations for the Classification of Mobile Offshore Units, Part 7, Safety Systems, Hazardous Areas and Fire, June 2013, Lloyd’s Register, Global StandardsWorking Temperature
Definition(s)
Working Temperature
The temperature to which a particular piece of equipment is subjected during normal operations. Source: API RP 7G, Recommended Practice for Drill Stem Design and Operating Limits, Upstream Segment, Sixteenth Edition, August 1998 (Addendum 2: September 2009). Global StandardsWorking Temperature
Temperature to which a particular piece of equipment is subjected during normal operation. Source: API SPEC 7-1, Specification for Rotary Drill Stem Elements, First Edition, March 2006 (Addendum April 2011). Global StandardsWorkover
Definition(s)
Workover
Remedial work done to the equipment within a well, the well pipe work, or relating to attempts to increase the rate of flow. Source: IADC UBO / MPD Glossary, December 2011. Global StandardsWorkover
“Workover” means a procedure the operator undertakes that is intended to increase production but is not routine maintenance and includes:- re-entry into the well to drill deeper, to sidetrack to a different location, to recomplete for production or to restore production from a zone that has been temporarily abandoned;
- recompletion by re-perforation of a zone from which gas or oil has been produced or by perforation of a different zone;
- repair or replacement of faulty or damaged casing or related downhole equipment;
- fracturing, acidizing or installing compression equipment; or
- squeezing, cementing or installing equipment necessary for removal of excessive water, brine or condensate from the well bore in order to establish, continue or increase production from the well.
Workover
an operation in which a well is re-entered for the purpose of maintaining or repairing it. Regulation 2, DCR. Source: Oil & Gas UK, Guidelines on subsea BOP systems, Issue 1, July 2012, Global StandardsWorkover
“Workover” means an operation on a completed well that requires removal of the Christmas tree or the tubing (reconditionnement. 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 Guidance Source: Nova Scotia Offshore Petroleum Drilling and Production Regulations, SOR/2009-317, Canada, current to May 31, 2012. RegulationsWorkover Control System
Definition(s)
WOCS
The WOCS, also commonly referred to as the installation/workover riser package, provides the means to remotely control/monitor all of the required functions on the C/WO equipment, subsea tree and downhole equipment during the various phases of the C/WO operation. The WOCS usually consists of the following components: pumping unit to provide hydraulic power; main control panel; remote control panel on the drill floor; process shutdown panel near the production test equipment; emergency shutdown panels at main escape routes; umbilical(s) on powered winch(es). Source: API RP 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, Fourth Edition, Reaffirmed 2011. Global StandardsWorkover Riser
Definition(s)
Workover Riser
A workover riser is a riser that provides a conduit from the upper connection on the subsea tree to the surface, and which allows the passage of wireline tools into the wellbore. A workover riser is not run inside a drilling marine riser and therefore it shall be able to withstand the applied environmental forces, i.e. wind, waves and currents. A workover riser is typically used during installation/recovery of a subsea VXT, and during wellbore re-entries which require fullbore access but do not include retrieval of the tubing. A workover riser typically consists of the following (see Figure A.33): the tree running tool; a wireline coiled-tubing BOP, capable of gripping, cutting and sealing coiled tubing and wire; an emergency-disconnect package capable of high-angle release; retainer valve(s) to retain the fluid contents of the riser during an emergency disconnect; a stress joint to absorb the higher riser bending stresses at the point of fixation to the LWRP; intermediate riser joints; lubricator valve(s) to isolate the riser during loading/unloading of long wireline toolstrings; a surface tree for pressure control of the wellbore and to provide a connection point for a surface wireline lubricator system; a means of tensioning the riser, so that it does not buckle under its own weight. Source: API RP 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, Fourth Edition, Reaffirmed 2011. Global StandardsWorkover Riser
Jointed riser that provides a conduit from the subsea tree upper connection to the surface and allows for the passage of tools during workover operations of limited duration, and can be retrieved in severe environmental conditions. NOTE Historically, workover operations have normally been performed in open sea (i.e. for vertical tree systems), but can be performed inside a drilling riser, provided sufficient barrier elements are available. 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 StandardsWorkplace
Definition(s)
Workplace
Workplace has the meaning given in clause 3 of Schedule 3 to the Act. Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. RegulationsWorkplace
Workplace, in relation to a facility, means the whole facility or any part of the facility. Source: Offshore Petroleum and Greenhouse Gas Storage Act 2006, Australia, amended 2012. LegislationWorkplace
“Work place” means any place where an employee is engaged in work for the employer. Source: Nova Scotia Offshore Petroleum Occupational Health & Safety Requirements, Canada-Nova Scotia Offshore Petroleum Board, Canada, December 2000. RegulationsWorkplace
“Workplace” means any working area, or place, including an installation or marine vessel, where an employee is or is likely to be engaged in any occupation and includes any vehicle or mobile equipment used or likely to be used by an employee in an occupation. Source: Nova Scotia Offshore Petroleum Occupational Health & Safety Requirements, Canada-Nova Scotia Offshore Petroleum Board, Canada, December 2000. RegulationsWorkplace
Workplace shall mean the whole area intended to house workstations, relating to the immediate and ancillary activities and installations of the mineral-extracting industries through drilling, including accommodation, where provided, to which workers have access in the context of their work. Source: Concerning the minimum requirements for improving the safety and health protection of workers in the mineral-extracting industries through drilling (eleventh individual Directive within the meaning of Article 16 (1) of Directive 89/391/EEC), Council Directive 92/91/EEC of 3 November 1992. LegislationWorkplace
Any working area, or place, including an installation or marine vessel, where an employee is or is likely to be engaged in any occupation and includes any vehicle or mobile equipment used or likely to be used by an employee in an occupation. Note: OSH (NL) 1.1; C-NLOPB Other Requirements Respecting Occupational Health & Safety; OSH (NS) Element 1, Part 1, Section 1.1. 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 GuidanceWorkplace
The whole area of an installation, including accommodation, to which workers have access in the context of their work, (i.e., all areas on the MODU). 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 GuidelinesWorkplace
In this regulation “workplace” has the same meaning as in regulation 2(1) of the Workplace (Health, Safety and Welfare) Regulations 1992. Note: S.I. 1992/3004. Source: The Borehole Sites and Operations Regulations 1995, UK S.I. 1995/2038, 1995. RegulationsWork Place
space within a work area, allocated to one or more persons to complete work tasks related to production, inspection or maintenance work system combination of people and work equipment, acting together in the work process, at the work place, in the work environment, and under the conditions imposed by the work task working environment totality of all physical, chemical, biological and physiological factors at work that may affect the employees’ health and well-being through acute trauma or lasting exposure working environment analysis systematic work process including the following: - definition, limitation and breakdown of the installation, work systems and work areas with respect to one or more parameters to reduce the risk of human error and improve task performance, e.g. area activities during operation, type of equipment, chemical substance. 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 StandardsWorkspace
Definition(s)
Workspace
Volume allocated to one or more persons in the work system (2.2) to complete the work task (2.17). Source: ISO 6385:2016, Ergonomics principles in the design of work systems, Third Edition, September 2016. Global StandardsWorkstation
Definition(s)
Workstation
Combination and spatial arrangement of work equipment (2.6), surrounded by the work environment (2.8) under the conditions imposed by the work tasks (2.17). Source: ISO 6385:2016, Ergonomics principles in the design of work systems, Third Edition, September 2016. Global StandardsWorm
Definition(s)
Worm
A self-replicating, self-propagating, self-contained program that uses networking mechanisms to spread itself. From: CNSSI 4009. Source: NICCS™ Portal Cybersecurity Lexicon, National Initiative for Cybersecurity Careers and Studies (https://niccs.us-cert.gov/glossary) as of 11 November 2015, Global StandardsWorm
Computer program that can run independently, can propagate a complete working version of itself onto other hosts on a network, and may consume computer resources destructively [11]. Source: ANSI/ISA–99.00.01–2007, Security for Industrial Automation and Control Systems, Part 1: Terminology, Concepts, and Models, 29 October 2007. National StandardWorst-Case Failure (WCF)
Definition(s)
Worst Case Failure
Design intent refer to the minimum remaining capacity after any relevant single failure or common cause (for a given operational mode). Source: Offshore Gangways, DNVGL-ST-0358, DNV GL, September 2017. Global StandardsWorst-Case Failure (WCF)
The identified single fault in the DP system resulting in maximum detrimental effect on DP capability as determined through the FMEA.
Source: IMO MSC.1/Circ.1580, GUIDELINES FOR VESSELS AND UNITS WITH DYNAMIC POSITIONING (DP) SYSTEMS, 16 June 2017, International Maritime Organization. Regulatory GuidanceWorst-Case Failure (WCF)
Worst-Case Failure (WCF) means the identified single fault in the DP system resulting in maximum detrimental effect on DP capability as determined through the FMEA. Source: IMO MSC.1/Circ.1580, GUIDELINES FOR VESSELS AND UNITS WITH DYNAMIC POSITIONING (DP) SYSTEMS, 16 June 2017, International Maritime Organization. Regulatory GuidanceWoven Roving
Definition(s)
Woven Roving
Cloth reinforcement structure in which fibre bundle tows are woven together in a single plane to provide reinforcement which is usually orientated to provide strength in the orthogonal 0° and 90° directions. Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global StandardsWPA
Definition(s)
WPA
Wi-Fi protected access. Source: DNVGL-RP-G108, Cyber security in the oil and gas industry based on IEC 62443, DNV GL, September 2017. Global StandardsWPQ
Definition(s)
WPQ
Welder performance qualification. Source: API SPEC 5DP, Specification for Drill Pipe, First Edition, August 2009. Global Standards Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global StandardsWPQR
Definition(s)
WPQR
Welding Procedure Qualification Record Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsWPS
Definition(s)
WPS
Welding procedure specification. Source: API 570, Piping Inspection Code: In-service Inspection, Rating, Repair, and Alteration of Piping Systems, Fourth Edition, February 2016, with Addendum May 2017. Global Standards Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global Standards Source: API SPEC 5DP, Specification for Drill Pipe, First Edition, August 2009. Global Standards Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global Standards Source: API SPEC 16A, Specification for Drill-through Equipment, Third Edition, June 2004 (Errata/Supplement November 2004). Global StandardsWPS
Weld procedure specification. Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards Source: API STD 53, Blowout Prevention Equipment Systems for Drilling Wells, Upstream Segment, Fourth Edition, November 2012. Global StandardsWPS
Written welding procedure that is qualified to provide direction for welding in accordance with requirements of this standard and describing the specific essential, nonessential, and supplementary essential variables required for each welding process.- NOTE: These variables and their meanings are defined in ASME BPVC Section IX, Article II and Article IV.
WPS
Document providing the required welding variables for a specific application to assure repeatability by properly trained welders and welding operators.- NOTE: These variables and their meanings are defined, respectively, in Article II of the ASME Boiler & Pressure Vessel Code, Section IX—Welding and Brazing Qualifications.
WPS
Welding Procedure Specifications. Source: API SPEC 16C, Specification for Choke and Kill Systems, First Edition, January 1993 (Reaffirmed 2001). Global Standards Source: API SPEC 16D, Specification for Control Systems for Drilling Well Control Equipment and Control Systems for Diverter Equipment, Upstream Segment, Second Edition, July 2004. Global Standards Source: API SPEC 16RCD, Specification for Drill Through Equipment—Rotating Control Devices, Upstream Segment, First Edition, February 2005. Global Standards Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsWR
Definition(s)
WR
Woven Roving. Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global StandardsWR
Cloth reinforcement structure in which fibre bundle tows are woven together in a single plane to provide reinforcement which is usually orientated to provide strength in the orthogonal 0° and 90° directions. Source: ISO 14692-1:2017, Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping — Part 1: Vocabulary, symbols, applications and materials, Second Edition, August 2017. Global StandardsWrench Tight
Definition(s)
Wrench Tight
When thread protector is tightened by hand using strap wrench, pipe wrench or thread protector wrench. Source: API RP 5A5, Field Inspection of New Casing, Tubing, and Plain-end Drill Pipe, Reaffirmed August 2010. Global StandardsWrought Product
Definition(s)
Wrought Product
Structure that contains no cast dendritic elements.
Source: API Specification 20E, Alloy and Carbon Steel Bolting for Use in the Petroleum and Natural Gas Industries, Second Edition, February 2017. Global Standards