Equipment
Diver Umbilical
Lines supplying divers with gas, communication or other services.
Documents
- 202628 Apr
Diver entanglement – umbilical caught around an anode
A diver’s umbilical snagged on a conductor-shaft anode at 18 msw after tidal current pushed it towards the structure. Slack allowed in-water decompression to continue while a stand-by diver freed the line. Planned diving time was not exceeded. The flash highlights attention to local environmental conditions and situational awareness.
- 20256 Mar
Diver lifted off seabed
A diver’s umbilical snagged on another bell’s clump weight, lifting the diver approximately 4–5 m above the seabed during adjustment. Services remained intact. The flash describes stopping the operation and clearing the umbilical, and recommends second-diver or ROV monitoring when divers pass close to objects being lifted.
- 20243 Jun
Diver’s umbilical trapped during a pipeline flooding operation
A saturation diver’s umbilical became trapped between pipelines when a newly laid line shifted during flooding, interrupting breathing gas. Another diver supplied pneumo gas and helped free the umbilical. The flash examines pipeline configuration, tidal current and umbilical routing, emphasising assessment of existing conditions and management of changing variables.
- 20249 Jan
Divers lifted off seabed by Clump Weight
During subsea diving, taut wire recovery pulled two divers from the seabed to 18 m above their maximum excursion depth, risking pressure-induced injuries. Both reported well after transfer and tests. The flash identifies communication failures and missing lift planning, and describes revised diver-clearance requirements, repeat-back instructions and stop-work measures.
- 202324 Jul
Restricted air supply to diver
A diver recovery drill was aborted after uneven basket recovery strained and kinked a standby diver’s umbilical, restricting his main air supply and prompting bailout. Both divers reached the surface safely. The flash identifies communication, planning and supervision shortcomings, and emphasises umbilical management and incorporating incident learning into procedures.
- 202311 Jan
Umbilical management – near miss
A diver’s umbilical became trapped when a pipeline rolled during crane-assisted removal of sleeper supports beneath a repair spool. The diver freed it and was unharmed. The flash identifies missing removal procedures, unrecognised umbilical hazards and absent change management, recommending a removal procedure and crew review.
- 202221 Apr
Diver experienced an air flow restriction
A surface-supplied diver experienced restricted air flow at 23msw and the dive was aborted without injury. Investigation identified a needle valve that failed to open properly, with possible overtightening linked to premature equipment fatigue. Actions included valve replacement, revised pre-dive checks and operating procedures, and a team emergency debrief.
- 202228 Jan
Near miss: Diver's umbilical drawn beneath a load
A diver’s umbilical was drawn beneath a GRP cover by suction during rigging hook-up. Vessel heave unexpectedly lifted the cover while crane active heave compensation was in use. The soft seabed prevented damage, with no service interruption or injuries. The risk assessment had not identified this umbilical movement hazard.
- 202128 Oct
Unexpected movement of conductor during diver dredging operations
During diver dredging before conductor cutting, a conductor toppled at a severance point, leaving an umbilical spanning between conductors. Crane restraint and vessel manoeuvring enabled release without injury or damage. The flash identifies incomplete task information and recommends conductor restraint, data verification, revised risk assessment and improved change management.
- 202130 Mar
Incorrect measurement and markings on divers umbilical
A diving operation was stopped after umbilical distance markings were found to use incorrect colours and a wrong measurement datum. Nobody was harmed, but checking and remarking caused lost time. The flash addresses unclear checking responsibilities, refresher training, mobilisation checks and audit comparison using a 50 m tape.
- 201917 Dec
Diver trapped by anchor chain
A diver searching for a pipeline end manifold became trapped by a moving anchor chain after his umbilical caught beneath it. Another diver cut the umbilical and assisted his recovery. The flash identifies inadequate hazard identification, procedures not followed, late information and inappropriate vessel movements, and reinforces dive supervision.
- 201923 Aug
Near miss: Diver’s umbilical trapped
During near-shore diving, an untended umbilical drifted against a seawater intake screen and became trapped when the automated bar started. Emergency stopping and manual reversal freed it; neither diver was injured. The flash identifies absent isolation and inadequate supervision, and records reviews of risk assessment, dive planning and permit requirements.
- 201913 May
Diver fatality during subsea lifting operations – update
This fatal diving incident update examines secondary life support activation after a trapped umbilical interrupted primary breathing gas during subsea spool relocation. Delayed completion of two-stage activation accelerated gas depletion. It reports equipment testing, refresher training and drills, and a decision to replace two-stage systems with single-stage activation.
- 20189 Nov
Finger injury: diver caught finger in bell door
A diver sustained a deep finger cut between a bell door and its retaining latch while repositioning an umbilical obstructing closure. The flash identifies incorrect stowage, limited risk awareness and missing hazard markings, and describes pinch-point checks, task risk assessments, toolbox talks and changes to equipment stowage.
- 20183 Sep
Diver fatality during subsea lifting operations
A diver died during spool relocation using lift bags at 172 metres seawater depth. Rigging caught the umbilical during uncontrolled spool ascent; subsequent trapping interrupted primary breathing gas. Secondary life support apparently functioned but did not prevent death. Pending investigation, interim recommendations address planning, supervision, documented instructions and stopping work when controls are inadequate.
- 20182 Aug
Near-miss: Divers’ umbilical rupture during routine maintenance
A diver’s umbilical breathing hose ruptured at about 14 bar during scheduled pressure testing, before final test pressure was reached. Mechanical damage may have contributed. The flash highlights visual inspection before testing, designated test areas, personnel notification, appropriate PPE and careful umbilical handling.
- 201814 Jun
Unapproved repair of diver gas supply umbilical
An undocumented gas-hose repair was discovered during demobilisation of a diver umbilical, which was subsequently scrapped. The heat-shrink-covered join could trap seawater and accelerate fitting corrosion, potentially interrupting breathing-gas supply. The member allowed such repairs only temporarily, pending a permanent fix, risk assessment and full management approval.
- 201811 Apr
Near miss: diver’s umbilical snagged by work basket during recovery to surface
A diver’s umbilical snagged on a tool basket being recovered by hydraulic crane, pulling him towards the diving basket roof before an effective all-stop intervention. The flash examines inadequate separation, umbilical slack and protruding pins, and describes improvements to communications, crane instructions and umbilical management.
- 20179 Jun
Near-misses during diving operations
Two diving near misses involved a bell approaching subsea lifting gear during vessel relocation and a stud bolt falling from a vessel towards a seabed worksite. A diver stopped the move, and dive control warned the exposed divers. Neither event caused injury or damage; subsequent arrangements included a dedicated tool basket.
- 201713 Feb
Near miss: Unidentified differential pressure led to diver’s umbilical getting trapped
An inshore diving near miss involved an umbilical drawn into a gravity-fed seawater intake and trapped by automated cleaning equipment. A second diver cut the line, enabling both divers to surface uninjured. Findings address undisclosed automation, inadequate isolation and risk review, with corrective actions covering lockout verification and dive-tender repositioning.
- 201622 Nov
Correct installation methods for diving umbilicals and hoses
Following a complaint about odour in a diver’s breathing hose, this flash describes fittings installed contrary to manufacturer recommendations. It explains potential pressure loss, water ingress and fitting failure associated with reusable fittings, and recommends standard swaged or crimped fittings while retaining hose bend restrictors.
- 201627 Jun
Vessel loss of position while diving in close proximity to a hydrocarbon facility
A diving vessel drifted over 40 metres after inadvertent deselection of its surge control disabled automatic positioning. A diver noticed his umbilical becoming taut. The alert examines vulnerable console layout, absent confirmation and ineffective excursion feedback, highlighting interface design and safeguards against unintended deactivation.
- 201624 Feb
Near-miss: Fouled diver umbilical
During a shallow-water saturation dive, slack from an extended umbilical was carried into aerated discharge and lifted around a caisson. Platform shutdown allowed its release, and both divers returned safely. The flash highlights overlooked discharge-flow hazards and recommends assessing umbilical length, routing and access during pre-job engineering and risk assessment.
- 20167 Jan
High potential near-miss: Failure of both divers’ breathing air supply and dive stage recovery winch
A diving near miss involved entanglement with a submerged winch exhaust hose weight, restricting the diver’s breathing supply and stalling the recovery winch. Emergency gas and use of the clump weight winch enabled safe recovery. Corrective actions addressed hose positioning, weight attachment, umbilical testing and deck risk assessment.
- 201329 Nov
Serious DP diving incident
A diving support vessel lost DP control following RBUS communication failure and drifted 240 m. A diver’s snagged umbilical severed, interrupting gas, hot water and communications. The flash describes recovery and medical monitoring, investigation findings without a definitive jamming cause, a firmware remedy and an improvement project for diving and marine operations.
- 201224 Jul
Near-miss: Bell umbilical damage incident
During diving bell recovery, insufficient umbilical tension allowed trapping between the cursor and bell, damaging the sheath and causing a small gas leak. Divers remained unharmed. The flash examines supervisor distraction and a visual-only differential alarm, recording umbilical re-termination, installation of an audible alarm and revised recovery risk assessments.
- 201225 Jun
Near-miss: Saturation diver lost gas supply
A saturation diver conducting pipeline free-span measurements at 100 m lost gas supplies when his umbilical became trapped at the bell interface. He returned unassisted on emergency gas and was unharmed. The flash examines bell movement, restricted access, emergency response, revised procedures and case-by-case assessment of bell positioning for rescue.
- 201125 Nov
Fatal diving incident
This safety flash outlines a fatal diving incident reported by the Danish Maritime Authority Investigation Board. A diver working underwater at approximately 41 metres lost his air supply following unintended squeezing of his umbilical. The flash directs readers to the board’s reports for further information.
- 201010 Nov
Precautions against jellyfish sting during diving operations
This safety flash addresses jellyfish stings and airborne irritants from contaminated diving suits. It describes tentacle particles remaining after inadequate cleaning and becoming airborne within diving systems. Precautions include task risk assessment, freshwater pressure washing, residue checks, umbilical cleaning, gloves, consideration of over-suits and medical personnel’s awareness of first aid procedures.
- 20109 Feb
Diver fouled on descending load
An air diver disconnecting an FPSO riser was dragged down to -70fsw after a lateral pull caused the riser to drop and part its webbing slings. His umbilical fouled on the crane wire. The flash addresses umbilical slack management, underwater sling selection, load calculations and separation of divers from planned load movements.
- 200923 Oct
Trapped diver umbilical incident resulting in diver fatality
A surface-supplied diver died after his umbilical became fouled on the seabed, with barge movement thought to have interrupted his gas supply. Wet-bell recovery dragged him out twice before the umbilical was freed. Company actions addressed barge movements, in-water tending, emergency briefings, debris surveys and pre-dive communication checks.
- 20095 Mar
Dive bell gas loss during internal bell checks
A diver’s umbilical accidentally opened a flooding valve during internal pre-dive checks aboard a dive support vessel, releasing gas and reducing bell pressure. The flash describes emergency re-pressurisation, cramped access and ergonomic problems, dual closed valves and securing mechanisms. It stresses correct checklists and recommends more structured, vessel-specific familiarisation.
- 20089 Oct
Near-miss incident involving a diver’s umbilical
A diver undertaking salvage work in UK territorial waters struggled with pulling on his umbilical despite additional slack. The supervisor believed tidal flow was responsible and proposed postponing the dive; communications were then lost. The flash describes permit and isolation checks and points readers to vessel-selection guidance.
- 20089 Oct
Uncontrolled ascent of spool and diver during a lifting bag operation
A diver became entangled in an air lift bag inverter line as a pipe spool ascended uncontrollably. Umbilical damage restricted gas flow and severed communications. He used emergency gas and cut himself free; no injuries were sustained. The investigation identified missing hold-back rigging and unclear sequencing in the dive plan.
- 200623 Aug
Lifting wire strop failure during air bag lift
A wire strop parted during inflation of an air lift bag used to align subsea flanges. The inverter line also failed, allowing the bag to surface. The diver remained clear of its ascent path. Reported corrective measures included rigging inspection, certification checks, pre-use checks and toolbox discussions.
- 20051 Mar
Near-miss: Diver’s umbilical severed by propeller
A diver working on an offshore platform riser surfaced unharmed after a lift boat’s slowly turning propeller drew in and severed the umbilical. The driveshaft securing procedure failed for unknown reasons. Recommendations require a padlocked purpose-built clamp, elevation to expose the propeller and rudder, and joint vessel–dive crew job hazard analysis.
- 20041 Dec
Loss of position of DP DSV
A DP diving support vessel moved some 107 metres off its worksite, leaving a diver unable to return unaided to the bell. He suffered carbon dioxide toxicity from overbreathing. The investigation attributed the movement to a soliton; recommendations address seasonal scheduling, vessel heading, radar watch, quick-release arrangements and diver communication.
- 20031 May
Diving fatality
A surface-supplied diver died after losing his helmet underwater. The flash examines an unsecured helmet fastening, a snagged umbilical, delayed recovery and limited video monitoring. It discusses manufacturer cautions about helmet modifications, emergency breathing provision in dive baskets, response exercises and individual monitors for working divers.
- Undated
Entanglement of diving umbilical cord with propeller of self-propelled crane Norma
A diver replacing a wreck marker in the Dover Strait had his umbilical entangled in Norma’s rotating propeller. He switched to bottled air, cut himself free after the propeller stopped and escaped uninjured. The investigation identified shortcomings in propulsion familiarisation, diving procedures, shipboard communication and safety management audits.
- Undated
Marathon/Technip - Alvheim/Skandi Arctic - Investigation into diving incident
The PSA investigates uncontrolled diving-bell lowering aboard Skandi Arctic during saturation diving at Kneler. Umbilical separation caused pressure loss before the bell reached the water; divers closed leaking valves and restored pressure using stored gas. The report examines handling-system operation, management deficiencies, competence and emergency arrangements, with no known health consequences.