“D” Circle

“D” Circle

Definition(s)

"D" Circle

A circle, usually imaginary unless the helideck itself is circular, the diameter of which is the “D” value of the largest helicopter the helideck is intended to serve. Source: NOGEPA Guideline 14, Helideck Operations and Procedures Manual, Netherlands, Version 2, December 2011. Global Standards
25% (50%) Drainage time

25% (50%) Drainage time

Definition(s)

25% (50%) Drainage Time

25% (50%) drainage time is the time for 25% (50%) of the liquid content of a foam to drain out. 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 Guidance 
D

D

Definition(s)

D

Maximum spudcan diameter below mudline.

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

Δ

Denotes a change in the variable. Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global Standards
D or D-value

D or D-value

Definition(s)

D or D-value

D or D-value means the largest dimension of the helicopter when rotor(s) are turning measured from the most forward position of the main rotor tip path plane to the most rearward position of the tail rotor path plane or helicopter structure. Source: IMO Resolution A.1023(26), Code for the Construction and Equipment of Mobile Offshore Drilling Units (2009 MODU Code), 2009. Global Standards
D&W

D&W

Definition(s)

D&W

Drilling & Well. Source: Norwegian Oil and Gas Association, Guideline No. 135, Recommended Guidelines for Classification and categorization of well control incidents and well integrity incidents, Rev. 4, 27 June 2017, National or Regional Standards
D-J Basin Fox Hills Protection Area

D-J Basin Fox Hills Protection Area

Definition(s)

D-J Basin Fox Hills Protection Area

D–J BASIN FOX HILLS PROTECTION AREA shall mean that area of the State consisting of Townships 5 South through Townships 5 North, Ranges 58 West through 70 West, and Township 6 South, Ranges 65 West through 70 West. Source: Oil and Gas Conservation Commission, Practice and Procedure, Code of Colorado Regulations, 2 CCR 404-1, February 2013. Regulations  
D-value

D-value

Definition(s)

D-value

D-value means the largest dimension of the helicopter used for assessment of the helideck when its rotors are turning. It establishes the required area of foam application. Source: IMO MSC.1/Circ.1431, Guidelines for the approval of helicopter facility foam fire-fighting appliances, 31 May 2012, International Maritime Organization. Regulatory Guidance
D100 Separation

D100 Separation

Definition(s)

D100 Separation

Particle size, expressed in micrometres, determined by plotting the percentage of aluminium oxide (aluminum oxide) sample separated by the test screen on the plot of cumulative mass fraction (as percent) retained versus U.S. Sieve Opening (expressed in micrometres) for the sieve analysis of the aluminium oxide test sample. NOTE 100 % of the particles larger than the D100 separation are retained by the test screen. Source: API RP 13C, Recommended Practice on Drilling Fluids Processing Systems Evaluation, Upstream Segment, Fourth Edition, December 2010. Global Standards  
DA

DA

Definition(s)

DA

Dynamic application. Source: API RP 17B, Recommended Practice for Flexible Pipe, Fourth Edition, July 2008. Global Standards  
da/dN

da/dN

Definition(s)

da/dN

Increment of crack growth for a given cycle. Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global Standards
DAC

DAC

Definition(s)

DAC

Defined limits placed on characteristics of materials, products, or services established by the organization, customer, and/or applicable specifications to achieve conformity to the product design. Source: API SPEC Q1, Specification for Quality Management System Requirements for Manufacturing Organizations for the Petroleum and Natural Gas Industry, Ninth Edition, June 2013 (Errata 2, March 2014). Global Standards

DAC

Design acceptance criteria. Source: API SPEC Q1, Specification for Quality Management System Requirements for Manufacturing Organizations for the Petroleum and Natural Gas Industry, Ninth Edition, June 2013 (Errata 2, March 2014). Global Standards  

DAC

Distance amplitude curve. Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards Source: API STANDARD 16AR, Standard for Repair and Remanufacture of Drill-through Equipment, First Edition, April 2017. Global Standards Source: API SPEC 6A, Specification for Wellhead and Christmas Tree Equipment, Twentieth Edition, October 2010 (Addendum November 2012). Global Standards
DAF

DAF

Definition(s)

DAF

Ratio of a dynamic action effect to the corresponding static action effect. NOTE 1 For a jack-up, the dynamic action effect is best simulated by means of a concentrated or distributed inertial loadset. It is usually not appropriate to factor the static actions to simulate the effects of dynamic actions. NOTE 2 The DAF excluding the mean values, KDAF,SDOF, can typically be obtained from a single degree-of-freedom (SDOF) calculation. In this case, it is defined as the ratio of the amplitude of a dynamic action effect to the amplitude of the corresponding static action effect for periodic excitation of a linear one degree-of-freedom model approximation of jack-up behaviour. NOTE 3 The DAF including the mean values, KDAF,RANDOM, can typically be obtained from a random wave calculation. In this case, it is defined as the ratio of the absolute value of a dynamic action effect to the absolute value of the corresponding static action effect, each including their mean value. NOTE 4 Adapted from ISO 19902:2007, definition 3.16. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global Standards  

DAF

Dynamic amplification factor. Source: ISO 19905-1:202, Petroleum and natural gas industries – Site-specific assessment of mobile offshore units – Part 1: Jack-ups. Global Standards  
Daily Drilling Report

Daily Drilling Report

Definition(s)

Daily drilling report

Daily drilling report means a report that includes:
  1. the name of the well; and
  2. the location of the well by latitude and longitude; and
  3. the water depth at the well; and
  4. the drilled depth; and
  5. the work carried out; and
  6. the lithology of formations penetrated; and
  7. details of any indication of hydrocarbons; and
  8. a summary of the material used; and
  9. drilling fluid losses; and
  10. a leak off test summary; and
  11. the geometry of the well bore; and
  12. the results of surveys made in the well bore; and
  13. the estimated daily and cumulative well costs.
Source: Offshore Petroleum and Greenhouse Gas Storage (Resource Management and Administration) Regulations 2011 (Select Legislative Instrument 2011 No. 54 as amended), Australia, prepared on 1 January 2012. Regulations
Damage

Damage

Definition(s)

Damage

Damage: damage to the interests referred to in Articles 49.2 and 49.3 of the Mijnbouwwet. Source: Mining Decree of the Netherlands, Netherlands, 2003 (as amended in 2007).  Legislation
Damage Mechanism

Damage Mechanism

Definition(s)

Damage Mechanism

Any type of deterioration encountered in the refining and chemical process industry that can result in flaws/defects that can affect the integrity of vessels (e.g. corrosion, cracking, erosion, dents, and other mechanical, physical, or chemical impacts). See API 571 for a comprehensive list and description of damage mechanisms.

Source: API 510, Pressure Vessel Inspection Code: In-service Inspection, Rating, Repair, and Alteration, Tenth Edition, May 2014, with Addendum May 2017. Global Standards  

Damage Mechanism

Any type of deterioration encountered in the refining and chemical process industry that can result in metal loss/flaws/ defects that can affect the integrity of piping systems (e.g. corrosion; cracking; erosion; dents; and other mechanical, physical, or chemical impacts). See API 571 for a comprehensive list and description of damage mechanisms that may affect process piping systems in the refining, petrochemical and chemical process industries.

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
Damage Rate

Damage Rate

Definition(s)

Damage Rate

The rate of deterioration other than corrosion, i.e. rate of cracking, rate of HTHA, creep rate, etc.

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
Damage Tolerance

Damage Tolerance

Definition(s)

Damage Tolerance

The quantity of deterioration or damage that a structure can withstand without failing. Source: API RP 2SIM, Structural Integrity Management of Fixed Offshore Structures, First Edition, November 2014. Global Standards
Damaged Condition

Damaged Condition

Definition(s)

Damaged Condition

“Damaged condition” means, with respect to a floating platform, the condition of the platform after it has suffered damage to the extent described in the Code referred to in subsection 57(9) (condition avariée). Source: Canada Oil and Gas Installations Regulations, SOR/96-111, Canada, current to May 1, 2014. Regulations Source: Canada Oil and Gas Installations Regulations, SOR/96-118, February 2013.Regulations Source: Nova Scotia Offshore Petroleum Installations Regulations, SOR/95-191, Canada, current to May 31, 2012. Regulations
Danger

Danger

Definition(s)

Danger

“Danger” means any existing or potential practice or condition or any current or future set of circumstances that poses an unacceptably high risk with respect to causing injury or illness to a person, whether or not the injury or illness occurs immediately or results in delayed effects that are deleterious to health or safety. Source:  Nova Scotia Offshore Petroleum Occupational Health & Safety Requirements, Canada-Nova Scotia Offshore Petroleum Board, Canada, December 2000. Regulations
Dangerous Atmosphere

Dangerous Atmosphere

Definition(s)

Dangerous Atmosphere

"Dangerous atmosphere" means an atmosphere that may expose workers to the risk of death, incapacitation, impairment of ability to self-rescue (i.e. to escape unaided from a space), injury or acute illness. Source: Resolution MEPC.210(63), 2012 Guidelines for safe and environmentally sound ship recycling, 2 March 2012, International Maritime Organization. Regulatory Guidance
Dangerous Chemicals

Dangerous Chemicals

Definition(s)

Dangerous Chemicals

Dangerous chemicals means any liquid chemicals designated as presenting a safety hazard, based on the safety criteria for assigning products to chapter 17. Source: Resolution MEPC.119(52), 2004 amendments to the International Code for the Construction and Equipment of Ships Carrying Dangerous Chemicals in Bulk (IBC Code), 15 October 2004. Regulatory guidance, International Maritime Organization
Dangerous Failure

Dangerous Failure

Definition(s)

Dangerous Failure

unsafe failure failure of a safety system which tends to impede a given safety action Note 1 to entry: This is a systemic failure in relationship with a given safety action performed by the safety system. Therefore this concept is irrelevant for an individual item on the shelves. Note 2 to entry: See Figure B.1.   fb1 Source: ISO/TR 12489:2013(E) Reliability modelling and calculation of safety systems. Global Standards
Dangerous Failures (or Unsafe Failures)

Dangerous Failures (or Unsafe Failures)

Definition(s)

Dangerous Failures (or Unsafe Failures)

Dangerous failures (or unsafe failures) are failures that have the potential to prevent the safety system from achieving its safety function when there is a true demand. A single dangerous failure is generally not sufficient to prevent a redundant safety system from performing its safety function (e.g. two dangerous failures are needed for a 2-out-of-3 voting system). Source: API STD 689, Collection and Exchange of Reliability and Maintenance Data for Equipment, First Edition, July 2007. Global Standards
Dangerous Goods

Dangerous Goods

Definition(s)

Dangerous Goods

Dangerous goods are those goods referred to in regulation VII/2. <Chapter II-2, part A, regulation 3>. Source: IMO Resolution MSC.99(73), amendments to the International Convention for the Safety of Life at Sea, 1974, as amended, 5 December 2000, International Maritime Organization. Legislation  

Dangerous Goods

Dangerous goods mean the substances, materials and articles covered by the IMDG Code. <Chapter VII, part A, regulation 1>. Source: IMO Resolution MSC.123(75), amendments to the International Convention for the Safety of Life at Sea, 1974, as amended, 24 May 2002, International Maritime Organization. Legislation  

Dangerous Goods

Definition of dangerous goods Dangerous goods comprise of all articles or substances which are capable of posing a significant risk to health, safety or property when transported, and which are classified according to I.C.A.O. Annex 18, Technical instructions for the safe transport of dangerous goods by air and IATA. For the purpose of transportation dangerous goods have been divided into three (3) categories. They are: 1. Forbidden: Those, which are forbidden for transportation by air 2. Acceptable: Those items, which are acceptable for air transport, provided all the special provisions concerning packaging; quantity and compatibility are complied with. 3. Excepted: Known items in general use such as, after shave lotions, perfumes etc. this being directed at passengers and their baggage. Source: NOGEPA Guideline 14, Helideck Operations and Procedures Manual, Netherlands, Version 2, December 2011. Global Standards
Dangerous Goods in Sold Form in Bulk

Dangerous Goods in Sold Form in Bulk

Definition(s)

Dangerous Goods in Solid Form in Bulk

Dangerous goods in solid form in bulk means any material, other than liquid or gas, consisting of a combination of particles, granules or any larger pieces of material, generally uniform in composition, which is covered by the IMDG Code and is loaded directly into the cargo spaces of a ship without any intermediate form of containment, and includes such materials loaded in a barge on a barge-carrying ship. <Chapter VII, part A-1, regulation 1>. Source: IMO Resolution MSC.123(75), amendments to the International Convention for the Safety of Life at Sea, 1974, as amended, 24 May 2002, International Maritime Organization. Legislation
Dangerous Occurrence

Dangerous Occurrence

Definition(s)

Dangerous occurrence

Dangerous occurrence has the meaning given by subregulation 2.41 (2). Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. Regulations  

Dangerous occurence

For the definition of dangerous occurrence in clause 3 of Schedule 3 to the Act, an occurrence, at a facility, that is specified in the following table is a dangerous occurrence.
  1. An occurrence that did not cause, but could reasonably have caused:
    1. the death of, or serious personal injury to, a person; or
    2. a member of the workforce to be incapacitated from performing work for the period mentioned in subregulation (1)
  2. A fire or explosion
  3. A collision of a marine vessel with the facility
  4. An uncontrolled release of hydrocarbon vapour exceeding 1 kilogram
  5. An uncontrolled release of petroleum liquids exceeding 80 litres
  6. A well kick exceeding 8 cubic metres (or 50 barrels)
  7. An unplanned event that required the emergency response plan to be implemented
  8. Damage to safety-critical equipment
  9. An occurrence to which items 1 to 8 do not apply that:
    1. results in significant damage to a pipeline (for example, reducing the capacity of the pipeline to contain petroleum or greenhouse gas substance flowing through it); or
    2. is likely to have a result of a kind mentioned in paragraph (a); or
    3. is of a kind that a reasonable pipeline licensee would consider to require immediate investigation
  10. Any other occurrence of a kind that a reasonable operator would consider to require an immediate investigation.
Note: The meaning of facility is explained in subregulation 1.5 (1). Source: Offshore Petroleum and Greenhouse Gas Storage (Safety) Regulations 2009 (Select Legislative Instrument 2009 No. 382 as amended), Australia, prepared on 1 January 2012. Regulations  

Dangerous occurence

Dangerous occurrence means an occurrence declared by the regulations to be a dangerous occurrence for the purposes of this definition. Source: Offshore Petroleum and Greenhouse Gas Storage Act 2006, Australia, amended 2012. Legislation  

Dangerous occurence

In this regulation, dangerous occurrence means any of the following events that arose out of or in connection with petroleum operations:
(a) an event that did not cause, but might reasonably have caused, a major accident:
(b) a well kick that either—
(i) exceeded 8 cubic metres (or 50 barrels); or
(ii) required the well to be shut-in:
(c) an uncontrolled release of hydrocarbon vapour exceeding 1 kilogram:
(d) an uncontrolled release of petroleum liquids exceeding 80 litres:
(e) the failure of any part of a well whose failure would cause or contribute to, or whose purpose is to prevent or limit the effect of, the unintentional release of fluids from a well or a reservoir being drawn on by a well:
(f) damage to, or failure of, a safety-critical element that required intervention to ensure it will operate as designed:
(g) a fire or explosion at an installation:
(h) the uncontrolled or unintentional release or escape of any substance (other than petroleum) on or from an installation, where that release or escape had the potential to cause death or serious harm to any person:
(i) an unintended collapse of—
(i) an installation; or
(ii) any part of an installation; or
(iii) any plant on an installation, where that collapse jeopardised, or could have jeopardised, the integrity of the installation:
(j) subsidence or local collapse of the seabed or ground that could have affected the foundations, or the integrity, of an installation:
(k) an unplanned event (other than a false alarm) that required the emergency response plan to be implemented:
(l) damage to an installation, caused by adverse weather conditions, earthquakes, or other natural events, that had the potential to cause death or serious harm of any person: (m) a collision between a vessel, aircraft, or vehicle and an installation that resulted in damage to the installation, the vessel, the aircraft, or the vehicle:
(n) a failure of equipment required to maintain a floating offshore installation on station:
(o) an incident involving loss of stability or buoyancy of a floating offshore installation. Source: Health and Safety in Employment (Petroleum Exploration and Extraction) Regulations 2013, SR 2013/208, New Zealand, as of May 2013. Regulations
Dangerous State

Dangerous State

Definition(s)

Dangerous State

state of the process when safety is not achieved Note 1 to entry: A dangerous state is the result of the occurrence of a critical dangerous failure (3.2.4, Figure B.1).   fb1 Source: ISO/TR 12489:2013(E). Global Standards
Dangerous Substance

Dangerous Substance

Definition(s)

Dangerous substance

A dangerous substance is a material possessing flammable or explosive properties as addressed in 1.3.1.1, Item a, or a toxic material as described in 1.3. l. 1, Item b. Source: API RP 750, Management of Process Hazards, First Edition, January 1990. Global Standards
Dangerous Substances or Devices

Dangerous Substances or Devices

Definition(s)

Dangerous Substances or Devices

Any material, substance, or item that reasonably has the potential to cause a security incident.

Source: API RP 781 Security Plan Methodology for the Oil and Natural Gas Industries.1st Ed. September 2016. Global Standards
Darcy

Darcy

Definition(s)

Darcy

Permeability of a porous medium, where one darcy is the flow of a single-phase fluid of 1 cP viscosity that completely fills the voids of the porous medium, flowing through the medium under conditions of viscous flow at a rate of 1 ml s-1 cm-2 cross-sectional area and under a pressure or equivalent hydraulic gradient of 1 atm cm -1. NOTE 1 cP 1= mPa s. Source: API RP 13B-1, Recommended Practice for Field Testing Water-based Drilling Fluids, Fourth Edition, March 2009. Global Standards