Glossary
Browse the IADC Lexicon alphabetically or by category. Get comprehensive definitions of drilling industry terms.
Transit Conditions
Definition(s)
Transit Conditions
Transit conditions means conditions wherein a unit is moving from one geographical location to another. Source: IMO resolution MSC.267(85), International Code on Intact Stability, 2008 (2008 IS Code), 4 December 2008, International Maritime Organization. Regulatory Guidance Source: IMO Resolution MSC.267(85), adoption of the International Code on Intact Stability, 2008 (2008 IS Code), 4 December 2008, International Maritime Organization. Regulatory GuidanceTransit Conditions
All unit movements from one geographical location to another. Source: Offshore Standard DNV-OS-C101, Design of Offshore Steel Structures, General (LRFD Method, Det Norske Veritas, April 2011. Global Standards Source: Rules and Regulations for the Classification of Mobile Offshore Units, Part 1, Regulations, June 2013, Lloyd’s Register, Global StandardsTransit Conditions
All wet vessel movements from one geographical location to another. Source: Rules for Classification – Offshore units, DNVGL-OU-0101, Offshore drilling and support units, DNV GL, July 2015. Global StandardsTransmission and Resolution Error
Definition(s)
Transmission and Resolution Error
Transmission and resolution error: error which is caused by the method used to transmit the original information to a receiving device. Such method may have a limited capability to code any possible value of the information e.g. step output with 1/6º resolution. This error is caused by the method used inside the THD and at its output to code the information. Source: IMO Resolution MSC.116(73), Recommendation on Performance Standards for Marine Transmitting Heading Devices (THDs), 1 December 2000, International Maritime Organization. Regulatory GuidanceTransmitting Part
Definition(s)
Transmitting Part
Transmitting part: device which receives a heading information from the sensing part and convert to the required accurate signal. Source: IMO Resolution MSC.116(73), Recommendation on Performance Standards for Marine Transmitting Heading Devices (THDs), 1 December 2000, International Maritime Organization. Regulatory GuidanceTransport
Definition(s)
To transport
Handling of materials and transport routes, access and evacuation routes: The terms transport, access and evacuation routes also include stairs, doors, hatches, etc. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceTo transport
“To transport” means to undertake any operation in order to move the petroleum produced by the concessionaire from production fields to storage places, points of sale or disposal, points of purchase, and points of export, and also includes to move such petroleum between the said points and places. Source: Law of Information Energy, Petroleum Act B.E. 2514 (1971), Thailand, as of June 2013. LegislationTravel Time
Definition(s)
Travel Time
“Travel time" as mentioned in the fourth subsection, will also include waiting for transport. Such travel time will not be counted as working hours. Source: Guidelines Regarding the Framework Regulations, Norway, updated December 2012. Regulatory GuidanceTread
Definition(s)
Tread
Tread means the step of an inclined ladder or step for the vertical access opening. Source: IMO Resolution MSC.158(78), amendments to the Technical provisions for means of access for inspections (Resolution MSC.133(76)), 20 May 2004, International Maritime Organization. Regulatory GuidanceTreatment
Definition(s)
Treatment
Treatment―as applied to Type A Facilities (defined herein), excluding Transfer Stations, treatment shall be defined as any method, technique, or process capable of hanging the physical and/or chemical characterization or composition of E and P Waste so as to reclaim salvageable hydrocarbons, process reusable material, reduce waste volume (volume reduction), neutralize waste, reduce §549 criteria concentration(s) or otherwise render the waste more suitable for handling, storage, transportation, and/or disposal. Source: Natural Resources, Office of Conservation – General Operations, Louisiana Administrative Code, Title 43, Part XIX, March 2013. RegulationsTreatment
Any method, technique, or process, including neutralization, designed to change the physical, chemical, or biological character or composition of any hazardous waste so as to neutralize such waste, to recover energy or material resources from the waste, or to render such waste non-hazardous or less hazardous, safer to transport, store, or dispose of, amenable for recovery or storage, or reduced in volume. The term does not include any activity that might otherwise be considered treatment that is exempt from regulation under this section (such as neutralization of caustic or acidic fluids in an elementary neutralization unit). Source: Oil and Gas Division, Texas Administrative Code, Title 16, Chapter 3, February 2013. RegulationsTreatment
Treatment means a process which may use a mechanical, physical, chemical or biological method to remove or render sterile, invasive or potentially invasive aquatic species fouling a ship. Source: Resolution MEPC.207(62), 2011 Guidelines for the control and management of ships' biofouling to minimize the transfer of invasive aquatic species, 15 July 2011, International Maritime Organization. Regulatory GuidanceTreatment Rated Capacity (TRC)
Definition(s)
Treatment Rated Capacity (TRC)
Treatment Rated Capacity (TRC) is the maximum continuous capacity expressed in cubic metres per hour for which the BWMS is type approved. It states the amount of ballast water that can be treated per unit time by the BWMS to meet the standard in regulation D-2 of the Convention. Source: Resolution MEPC.174(58), revised Guidelines for approval of ballast water management systems (G8), 10 October 2008, International Maritime Organization. Regulatory GuidanceTrue Heading
Definition(s)
True Heading
True heading: horizontal angle between the vertical plane passing through the true meridian and the vertical plane passing a through the craft’s fore and aft datum line. It is measured from true north (000º) clockwise through 360º. Source: IMO Resolution MSC.116(73), Recommendation on Performance Standards for Marine Transmitting Heading Devices (THDs), 1 December 2000, International Maritime Organization. Regulatory GuidanceTSA
Definition(s)
TSA
Transportation Security Agency.
Source: API RP 781 Security Plan Methodology for the Oil and Natural Gas Industries.1st Ed. September 2016. Global StandardsTSA
Training Services Agency. Source: Commercial Diving Projects Offshore, Diving at Work Regulations 1997, Approved Code of Practice (UK HSE L103), First Edition, 1998. Regulatory GuidanceTurnaround/Revision Stop
Definition(s)
Turnaround/Revision Stop
A turnaround/revision stop is a pre-planned period in which the operations on the facility have been shut down in order to carry out an accumulated portfolio of extensive and necessary maintenance, modifications, improvements, inspections etc. Source: Guidelines Regarding the Activities Regulations, Norway, updated December 2012. Regulatory GuidanceTurnbuckles and Lashing Rods
Definition(s)
Turnbuckles and Lashing Rods
Turnbuckles and lashing rods include similar cargo securing devices. (Refer to standard ISO 3874, Annex D Lashing rod systems and tensioning devices.). Source: IMO MSC.1/Circ.1352, amendments to the Code of Safe Practice for Cargo Stowage and Securing (CSS Code), 30 June 2010, International Maritime Organization. Regulatory GuidanceType
Definition(s)
Type
Components of common function.- Note: 1 to entry: Pipes, prime connections, flanges, reducers, tees and elbows are examples of different component types.
Type
A product with unique characteristics or functionality, which differentiates it from other equipment.
Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global StandardsType
SSSV equipment with unique characteristics which differentiate it from other functionally similar SSSV equipment.- EXAMPLES: SCSSV, velocity-type SSCSV and low-tubing-pressure-type SSCSV are types of SSSV.
Type
Type, in relation to the design of a lifeboat release and retrieval system, means an identical lifeboat release and retrieval system of given safe working load, make and model (thus any change to the materials of construction, design arrangement or dimensions constitutes a change of type). Source: IMO MSC.1/Circ.1392, Guidelines for evaluation and replacement of lifeboat release and retrieval systems, 27 May 2011, International Maritime Organization. Regulatory GuidanceType A Foam Concentrates
Definition(s)
Type A Foam Concentrates
Type A foam concentrates are alcohol-resistant or multi-purpose foam concentrates. Source: IMO MSC.1/Circ.1312, Revised Guidelines for the performance and testing criteria, and surveys of foam concentrates for fixed fire-extinguishing systems, 10 June 2009, International Maritime Organization. Regulatory GuidanceType B Foam Concentrates
Definition(s)
Type B Foam Concentrates
Type B foam concentrates are all regular type foam concentrates that are not alcohol-resistant, including fluoroprotein and aqueous film-forming (AFF) foam concentrates. Source: IMO MSC.1/Circ.1312, Revised Guidelines for the performance and testing criteria, and surveys of foam concentrates for fixed fire-extinguishing systems, 10 June 2009, International Maritime Organization. Regulatory GuidanceUKCS
Definition(s)
UKCS
United Kingdom continental shelf. Source: A Guide to the Offshore Installations and Pipelines Works (Management and Administration) Regulations 1995, Guidance on Regulations (UK HSE L70), Second Edition, 2002. Regulatory GuidanceUKOOA
Definition(s)
UKOOA
United Kingdom Offshore Operators Association. Source: API RP 17L2, Recommended Practice for Flexible Pipe Ancillary Equipment, First Edition, March 2013. Global Standards Source: Prevention of Fire and Explosion, and Emergency Response on Offshore Installations, Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995, Approved Code of Practice and guidance (UK HSE L65), Second Edition, 1997. Regulatory Guidance Source: A Guide to the Offshore Installations and Pipelines Works (Management and Administration) Regulations 1995, Guidance on Regulations (UK HSE L70), Second Edition, 2002. Regulatory Guidance 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 StandardsUnacceptable Risk
Definition(s)
Unacceptable Risk
Level of risk at which, given costs and benefits associated with further risk reduction measures, action is deemed to be warranted at a given point in time.
Source:API STANDARD 780, Security Risk Assessment Methodology for the Petroleum and Petrochemical Industries, First Edition, May 2013. Global StandardsUnacceptable Risk
Definition: level of risk at which, given costs and benefits associated with further risk reduction measures, action is deemed to be warranted at a given point in time. Sample Usage: The presence of contaminants in excess of a certain level represents an unacceptable risk to public health. Source: DHS Risk Lexicon, U.S. Department of Homeland Security, 2010 Edition. September 2010 Regulatory GuidanceUnambiguous Command Structure
Definition(s)
Unambiguous Command Structure
An unambiguous command structure means that the flow of signals and command hierarchy is clearly stated. Source: Guidance Notes on Petroleum and Natural Gas (Safety in Offshore Operations) Rules, 2008, Oil Industry Safety Directorate (India), 2012. Regulatory GuidanceUnambiguous Command Structure
An unambiguous command structure as mentioned in the second subsection, means that the flow of signals and command hierarchy are clearly stated. Source: Guidelines Regarding the Facilities Regulations, Norway, updated December 2012. Regulatory Guidance Source: Guidelines Regarding the Technical and Operational Regulations, Norway, updated December 2012. Regulatory GuidanceUnauthorized Discharge
Definition(s)
Unauthorized Discharge
An unauthorized discharge occurs when: • A substance or mixture is discharged from a production or drilling installation in an amount or at a concentration in excess of the limits described in the Operator’s Environmental Protection Plan, or the substance or the manner of discharge is not described in that plan Note: In respect of the definition of pollution as per DPR 1(1); C NLOPB/CNSOPB/NEB Environmental Protection Plan Guidelines, March 2011. • A toxic fluid is discharged from a diving installation or an accommodations installation. Note: INST 70(1). • A discharge occurs from a geophysical vessel that constitutes a threat to the environment Note: GPR 27. 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 GuidanceUncertainty
Definition(s)
Uncertainty
Degree to which a calculated, estimated, or observed value may deviate from the true value.
Source:API STANDARD 780, Security Risk Assessment Methodology for the Petroleum and Petrochemical Industries, First Edition, May 2013. Global StandardsUncertainty
Degree to which a calculated, estimated, or observed value may deviate from the true value. Sample Usage: The uncertainty in the estimate was due to a lack of information for the particular environment and situation. Annotation:- Uncertainty may stem from many causes, including the lack of information.
- The concept of uncertainty is useful in understanding that likelihoods and consequences can oftentimes not be predicted with a high degree of precision or accuracy.
UNCLOS
Definition(s)
UNCLOS
UNCLOS means the United Nations Convention on the Law of the Sea, 1982. Source: IMO MSC.1/Circ.1251, Guidelines on the control of ships in an emergency, 19 October 2007, International Maritime Organization. Regulatory GuidanceUnified Requirements
Definition(s)
Unified Requirements
Unified Requirements means IACS Unified Requirements for Polar Class Ships (UR-I). Source: IMO resolution A.1021(26), Guidelines for ships operating in polar waters, 18 January 2010, International Maritime Organization. Regulatory GuidanceUnmitigated Risk
Definition(s)
Unmitigated Risk
Risk that remains after risk management measures have been implemented. Sample Usage: While increased patrols lessened the likelihood of trespassers, residual risk remained due to the unlocked exterior doors. Source: DHS Risk Lexicon, U.S. Department of Homeland Security, 2010 Edition. September 2010 Regulatory GuidanceUnmitigated Risk (residual risk)
Definition(s)
Unmitigated Risk (residual risk)
Risk that remains after risk management measures have been implemented. Residual risk is ―risk that remains after risk management measures have been implemented‖). Sample Usage: A risk to the facility that was not considered in the risk assessment was a potential unmitigated risk. Source: DHS Risk Lexicon, U.S. Department of Homeland Security, 2010 Edition. September 2010 Regulatory GuidanceUnprotected Exposure
Definition(s)
Unprotected exposure
A worker’s exposure to noise, measured at the worker’s ear position, which does not take into account any protection afforded by person hearing protectors (NOHSC 1007). The correct notation for unprotected exposure is LAeq,8h. Note: Measurement at the worker’s “ear position” means a measurement taken at a horizontal distance of approximately 10cm to no more than 20cm from the entrance of the external canal of the ear receiving the higher noise level. Source: NOPSEMA Guidance Note: Noise Management—Principles of Assessment and Control, N-09000-GN0401, Australia, Revision 3, December 2011. Regulatory GuidanceUntreated Sewage
Definition(s)
Untreated Sewage
Untreated Sewage means sewage that has not been treated by a type approved sewage treatment plant, or that has not been comminuted and disinfected. Source: Resolution MEPC.173(58), Guidelines for ballast water sampling (G2), 10 October 2008, International Maritime Organization. Regulatory GuidanceUsability
Definition(s)
Usability
The extent to which systems can be used by users to achieve specified goals with effectiveness, efficiency and satisfaction, in a specified context of use. Source: IMO MSC.1/Circ.1512, Guideline on Software Quality Assurance and Human-Centred Design for e-navigation, 8 June 2015, International Maritime Organization. Regulatory GuidanceUsability
Extent to which a system, product or service can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use.- Note 1 to entry: Systems, products or services are part of work systems (2.2) and used by workers (2.4) within those systems.
- Note 2 to entry: In this International Standard, the context of use is within a work system.