Glossary
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Assessment Codes
Definition(s)
Assessment Codes
Codes used in this document to describe the type and extent of assessment during risk based Verification.
Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsMPQT
Definition(s)
MPQT
Manufacturing Procedure Qualification Test. Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsOSS
Definition(s)
OSS
DNV Offshore Service Specification. Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsNB
Definition(s)
NB
Notified Body Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsILO
Definition(s)
ILO
International Labour Organisation Source: Verification of Lifting Appliances for the Oil and Gas Industry, DNV-OSS-308, October 2010, Det Norske Veritas AS, Global StandardsZone 2
Definition(s)
Zone 2
Place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas or vapour is not likely to occur in normal operation but, if it does occur, will persist for a short period only. Source: IEC 60079-14:2013, Explosive atmospheres – Part 14: Electrical installations design, selection and erection, Edition 5.0, November 2013. Global StandardsZone 2 (hazardous area)
An area in which an explosive gas-air mixture is unlikely to occur, and if it does occur, it will only persist for short period. 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 StandardsZone 1
Definition(s)
Zone 1 (hazardous area)
An area in which an explosive gas-air mixture is likely to occur under normal operating conditions. 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 StandardsZone 1
Place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas or vapour is likely to occur in normal operation occasionally. Source: IEC 60079-14:2013, Explosive atmospheres – Part 14: Electrical installations design, selection and erection, Edition 5.0, November 2013. Global StandardsZone 0 (hazardous area)
Definition(s)
Zone 0 (hazardous area)
An area in which an explosive gas-air mixture is continuously present or present for long periods. 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 StandardsZone 0
Place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas or vapour is present continuously or for long periods or frequently. Source: IEC 60079-14:2013, Explosive atmospheres – Part 14: Electrical installations design, selection and erection, Edition 5.0, November 2013. Global StandardsStorage Spaces
Definition(s)
Storage Spaces
Storage spaces are spaces used for bulk storage and trunks to such spaces, e.g., crude oil storage tanks on oil storage units. 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 StandardsSteel or Other Equivalent Material
Definition(s)
Steel or Other Equivalent Material
Steel or other equivalent material means any non-combustible material which, by itself, or due to insulation provided, has structural and integrity properties equivalent to steel at the end of the applicable exposure to the standard fire test (e.g., aluminium alloy with appropriate insulation). 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 StandardsSemi-enclosed Space
Definition(s)
Semi-enclosed Space
A semi-enclosed space is considered to be a space which is adjoining an open area, where the natural ventilation conditions within the space are restricted by structures such as decks, bulkheads or windbreaks in such a manner that they are significantly different from those appertaining to the open deck, and where dispersion of gas may be impeded. 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 StandardsProcess Plant
Definition(s)
Process Plant
Drilling, process plant and industrial machinery and components are the machinery and components which are used in connection with the operation of drilling, production and process systems. 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 StandardsOpen-air Area
Definition(s)
Open-air Area
An open-air area is one without stagnant regions where vapours are rapidly dispersed by wind and natural convection. Typically, air velocities will rarely be less than 0,5 metres per second and will frequently be above 2 metres per second. 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 StandardsLighter Than Air
Definition(s)
Lighter Than Air
Gases and vapours are considered lighter than air when their density, on release to atmosphere, is less than approximately 0,75 relative to the ambient air. 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 StandardsJet-fire Test
Definition(s)
Jet-fire Test
A jet-fire test is used to determine how effective the passive fire protection materials are in withstanding an actual jet fire. The test is not intended to replace the hydrocarbon fire test. Some Administrations require fire protection materials to be assessed by this method and, where requested, LR can advise on the detailed requirements. 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 Standards‘H’ Class Divisions (fire divisions)
Definition(s)
‘H’ Class Divisions (fire divisions)
‘H’ Class divisions are those divisions formed by fire walls and decks which comply with the construction and integrity requirements for ‘A’ Class divisions, 2.6.1(a) and (b) and with the following: (a) They are to be so constructed as to be capable of preventing the passage of smoke and flame up to the end of the one hour hydrocarbon fire test. (Note that some administrations may require the ‘H’ Class division integrity to be maintained for 120 minutes). (b) They are to be insulated with approved non-combustible materials such that the average temperature, on the unexposed side, when exposed to a hydrocarbon fire test, will not rise more than 140°C above the original temperature, nor will the temperature at any one point, including any joint, rise more than 180°C above the original temperature within the time listed below: Class ‘H-120’ - 120 minutes Class ‘H-60’ - 60 minutes Class ‘H-0’ - 0 minutes. (c) A test of a prototype fire wall or deck may be required to ensure that it meets the above requirements for integrity and temperature rise. 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 StandardsFire and Explosion Evaluation (FEE)
Definition(s)
Fire and Explosion Evaluation (FEE)
The FEE is an assessment of the potential fire loadings and blast pressures, based on the specific hazards associated with the general layout of the unit, production and process activities and operational constraints. 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 StandardsFEE
Definition(s)
FEE
Fire and Explosion Evaluation 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 StandardsDrilling Plant
Definition(s)
Drilling Plant
Drilling, process plant and industrial machinery and components are the machinery and components which are used in connection with the operation of drilling, production and process systems. 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 StandardsInternal Zones
Definition(s)
Internal Zones
Ballast tanks, liquid storage tanks, and other compartments Source: Rules and Regulations for the Classification of Mobile Offshore Units, Part 8, Corrosion Controls, June 2013, Lloyd’s Register, Global StandardsBoot Topping Zone
Definition(s)
Boot Topping Zone
That part of the external structure between the maximum design operating draught and the light design operating draught. For column-stabilised units, see Table 1.1.1. Source: Rules and Regulations for the Classification of Mobile Offshore Units, Part 5, Main and Auxiliary Machinery, June 2013, Lloyd’s Register, Global StandardsEssential Services
Definition(s)
Essential Services
Essential services are those necessary for the propulsion and safety of the unit, such as the following:- Electric propulsion equipment.
- Thruster systems for dynamic positioning.
- Thruster systems for positional mooring.
- Abandonment systems dependent on electric power.
- Ventilation systems for hazardous areas and those maintained at an overpressure to exclude the ingress of dangerous gases.
- Wellhead control and disconnection systems dependent on electric power.
- Electric starting systems for oil engines.