Extended Operational and Trade Vocabulary

Saturation Diving and Offshore Diving Operations glossary (page 2)

The commercial-diving vocabulary: abandonment lines and severed umbilicals, absolute pressure and diver acclimatization, saturation-system and diving-bell operation, gas-mixture and partial-pressure management, decompression schedules, and the surface-supplied and life-support terms. Grounds each term in the diving physiology, the decompression theory, or the saturation-diving operation it belongs to.

367 defined terms.

Showing 117 on this page (page 2 of 2).

N

NDT: Non-destructive testing of welds in monopiles, transition pieces, and jackets.
Newtsuit: Atmospheric diving suit by Hard Suits Inc.
Nitrox: Oxygen-enriched diving gas mix.
No-Stop Limit: Maximum bottom time at a depth that permits a direct ascent.
NOAA: National Oceanic and Atmospheric Administration of the United States.
NORSOK U-100: Norwegian standard for manned underwater operations.
NORSOK U-101: Norwegian standard for diving respiratory equipment.
NORSOK U-103: Norwegian standard for diving system underwater equipment.
North Ocean 102: McDermott DSV.
North Ocean 105: McDermott New Orleans-based DSV.
Nozzle: Restriction in chamber piping controlling fill rate.

O

OCC: Offshore Construction Contractor.
Open Bell: Wet bell without pressurized envelope, used as a stage for surface-supplied divers.
Open Circuit: Breathing system venting exhaled gas to ambient water.
Operations Manual: Statutory ISM-mandated documentation onboard.
Oronasal Mask: Inner mask within a helmet reducing CO2 dead space.
OSHA: US Occupational Safety and Health Administration.
OSHA 29 CFR 1910.401: US federal commercial diving operations standard.
Overpressure Relief: Safety valve protecting chambers from over-pressurization.
Oxygen Analyzer: Instrument measuring oxygen partial pressure or percentage.
Oxygen Cleaning: Special cleaning of components handling high-purity oxygen.
Oxygen Compatible Lubricant: Lubricant qualified for oxygen service such as Krytox.
Oxygen Partial Pressure: ppO2, the fraction of total pressure attributable to oxygen.
Oxygen Toxicity: Pulmonary or CNS injury from prolonged or high-pressure oxygen exposure.
Oxygen Window: Difference between inspired and venous oxygen partial pressures aiding off-gassing.

P

Paramagnetic O2 Analyzer: Servomex-style sensor exploiting oxygen's magnetic susceptibility.
Partial Pressure: Pressure exerted by one component of a gas mixture.
Pascal: SI unit of pressure, 1 N/m squared.
Penetrator: Sealed feed-through carrying signals or fluids through a chamber wall.
Personal Transfer Capsule: PTC, alternative term for a closed diving bell.
Pipelay Vessel: Specialist S-lay, J-lay or reel-lay construction vessel.
Pneumofathometer: Open tube measuring diver depth from surface gas back-pressure.
ppO2: Oxygen partial pressure, typically held at 0.4 to 0.5 bar in saturation.
Pressure Hull: Primary structural envelope of a hyperbaric chamber.
Pressure Vessel for Human Occupancy: PVHO, ASME-coded chamber category.
PVHO-1: ASME Safety Standard for Pressure Vessels for Human Occupancy.

Q

Q4000: Helix multi-service vessel used at Macondo.
Q5000: Helix Energy Solutions deepwater intervention vessel.
Q7000: Helix Energy Solutions semi-submersible intervention vessel.
Quick Connector: Push-fit connection on diver gas and hot water umbilicals.

R

RBI: Risk-Based Inspection scheme applied to subsea assets.
Reach rod: Mechanical linkage extending valve operation to remote position.
Rebreather: Closed or semi-closed circuit breathing apparatus.
Reclaim Helmet: Diver helmet routing exhaled gas back to the surface for reclaim.
Recompression: Re-pressurization of a casualty to treat decompression sickness.
Recompression chamber: Pressurized vessel used for decompression illness; rare onboard but standard on dive-support vessels.
Recreation Lock: Lock through which food, laundry, and entertainment items pass into the system.
Rever Offshore: Owner of former Bibby Offshore assets prior to Mermaid acquisition.
Reverse Profile: Repetitive dive in which a deeper dive follows a shallower one.
ROV: Remotely Operated Vehicle used for survey, hot tap support, and deep salvage work.
ROV Support: Use of an ROV to assist or supervise diver work.

S

SAA: Sub-aqua Association, UK recreational diver training agency.
Sanitary Lock: Lock for the disposal of waste from the living chamber.
SapuraOMV: Malaysian/Austrian operator partnering with Sapura Energy on offshore work.
Saturation: Equilibrium state in which tissue gas tension equals ambient inert gas pressure.
Saturation Control: Console and operator overseeing chamber and bell status.
Saturation Decompression: Slow ascent at typically 1 to 2 feet per hour from storage depth.
Saturation Diver: Diver living and working at storage pressure for the duration of a bell run series.
Saturation Diving: Long-duration deep diving with divers held at depth pressure.
Saturation System: Complete chamber, bell, gas, and life support assembly.
SCBA: Self-contained breathing apparatus.
Scrubber: Exhaust gas cleaning system used as an equivalent under MARPOL Annex VI Regulation 4.
SDC: Submersible Decompression Chamber, the formal term for a closed diving bell.
Self-Contained Diving: Diving with all gas carried by the diver, as in SCUBA.
Servomex: UK manufacturer of paramagnetic oxygen analyzers.
Seven Atlantic: Subsea 7 250 m saturation DSV with a 24-man dive system, delivered 2010.
Seven Falcon: Subsea 7 IRM vessel.
Seven Kestrel: Subsea 7 250 m saturation DSV delivered 2007.
Seven Pelican: Subsea 7 DSV.
Skandi Achiever: DOF-built diving support vessel.
Skandi Arctic: TechnipFMC chartered DSV.
Skandi Vinland: TechnipFMC chartered DSV.
Soda Lime: Calcium hydroxide-based CO2 absorbent used in scrubbers.
Splash zone: vertical area subject to spray, requiring protective coatings.
Stand-by Diver: Suited diver ready to enter the water on instruction of the supervisor.
Standard Diving Dress: Historic copper helmet and canvas suit equipment.
Star Canopus: Vessel involved in a 1978 Australian diving fatality.
Storage Depth: Pressure at which the saturation living chamber is maintained.
Submersible Decompression Chamber: SDC, formal name for the diving bell.
Subsea 7: Norwegian-British subsea construction company operating reel-lay and S-lay vessels including Seven Oceans and Seven Borealis.
Sur-D O2: Surface decompression on oxygen, a planned in-water plus chamber decompression method.
Surface Decompression: Procedure interrupting in-water decompression and completing it in a chamber.
Surface Demand: Breathing system regulated at the helmet with gas supplied from the surface.
Surface Supplied Air Diving: Diving on air with surface supply, the typical 0 to 50 m mode.
Surface Supplied Mixed Gas Diving: Heliox or trimix surface-supplied diving, 50 to 100 m.
Suspended Bell: Bell deployed but not yet bottomed at the worksite.

T

Tender: Small boat ferrying guests between ship and shore at anchor ports.
Tertiary Heating: Backup hot water supply for divers in event of primary loss.
Therapeutic Recompression: Treatment recompression of a DCS casualty.
Therapy Table: Recompression table such as US Navy Table 6 used for DCS treatment.
Thermal Conductivity Analyzer: Sensor measuring helium fraction by gas thermal conductivity.
Thomas Reuter: Common manufacturer reference for diving bell umbilicals.
Through-Water Communications: Acoustic comms with untethered divers.
Trimix: Breathing mix of nitrogen, helium, and oxygen used at shallower mixed-gas depths.
Trunk: Pressurized passage between chambers and the bell.
TUP: Transfer Under Pressure, movement of divers between chambers and bell at depth.
TUP Comex: Comex transfer-under-pressure system used in the Hydra trials.

U

Umbilical: Composite hose/cable bundle (electric, hydraulic, chemical, fiber).
Umbilical Length: Operational excursion radius of a working diver from the bell.
Umbilical Tender: Crew member feeding and recovering diver umbilical.
Underwater Welding: Wet or dry hyperbaric welding used for hull repairs during salvage.
US Navy Diving Manual: Reference document containing standard dive procedures and tables.
US Navy Table 4: Recompression table for severe DCS, now largely superseded by Table 6A.
US Navy Table 5: Recompression table for Type 1 DCS relieved within 10 minutes at 60 fsw.
US Navy Table 6: Primary recompression table for serious DCS on oxygen at 60 fsw.
US Navy Table 6A: Recompression table for arterial gas embolism with descent to 165 fsw.
US Navy Table 7: Saturation recompression table for life-threatening symptoms.
US Navy Table 9: Recompression table for residual symptoms after primary treatment.

V

Venous Gas Emboli: Inert gas bubbles in venous return detected post-dive by Doppler.
Vent Valve: Chamber valve discharging gas during decompression.
Visual Display Unit: Monitor in the dive control room showing bell and diver helmet video.

W

Water Lock: Lock containing water transfer between chamber and external.
Wet Bell: Open bell used as a stage for surface-supplied divers.
Wet Pot: Hyperbaric water-filled training chamber for diver simulation.
Wildrake: 1979 Norwegian sector diving fatality.
Workman M-Values: Maximum allowable supersaturation ratios from Robert Workman's tables.
Wreck Diving: Underwater inspection or salvage on sunken structures.