Subscribe to our Mailing Lists (It's free!)
Friday, March 24, 2023
SAFETY4SEA
  • Home
  • Safety
    • All
    • Accidents
    • Alerts
    • Loss Prevention
    • Maritime Health
    • Regulation
    • Safety
    • Seafarers
    • Security
    lessons learned

    Lessons learned: Safety warning issued about the hazards of flexible hose installations

    amsa mlc

    HRAS urges the Australian Government to reinforce its national legislative on seafarer welfare

    Multiple boats on fire at Seattle Marina

    Multiple boats on fire at Seattle Marina

    ReCAAP ISCReCAAP ISC One incident

    ReCAAP ISC: One incident of armed robbery 14 – 20 Mar

  • SEAFiT
    • All
    • Intellectual
    • Mental
    • Physical
    • Social
    • Spiritual
    Why sleep and mental health go hand-in-hand

    Why sleep and mental health go hand-in-hand

    Life coaching tips: How to maintain a good work-life balance

    Life coaching tips: How to maintain a good work-life balance

    Wabi sabi

    Wabi Sabi: Imperfection makes perfection at work

    sexual abuse

    Sexual abuse at sea: Where we stand

  • Green
    • All
    • Arctic
    • Ballast
    • Emissions
    • Fuels
    • Green Shipping
    • Pollution
    • Ship Recycling
    • Technology
    K Line adds kite on vessel to lower emissions

    K Line adds kite on vessel to lower emissions

    training maritime decarbonization

    Six companies join forces to build methanol tanker

    ClassNK answers FAQs on the EU-ETS

    ClassNK answers FAQs on the EU-ETS

    EU green shipping

    EU agrees to 2% mandate for green shipping fuels by 2025

  • Smart
    • All
    • Connectivity
    • Cyber Security
    • E-navigation
    • Energy Efficiency
    • Maritime Software
    • Smart
    NAPA: Simulation software aids in predicting CII

    NAPA: Simulation software aids in predicting CII

    Canada, UK join forces for R&D digital project on decarbonization

    Canada, UK join forces for R&D digital project on decarbonization

    technology

    How a joined-up approach to technology drives people performance

    New smart project aims to improve maritime logistics

    New smart project aims to improve maritime logistics

  • Risk
    • All
    • CIC
    • Detentions
    • Fines
    • PSC Case Studies
    • PSC Focus
    • Vetting
    australia sea mines

    AMSA imposes 90-day ban on Dutch vessel

    Singapore

    Eco Spark arrested in Singapore

    Liberia

    Liberia: key guidance for machinery space deficiencies

    orange county oil spill fines

    Taiwan’s Wan Hai Lines to pay $950,000 in civil penalties

  • Others
    • All
    • Diversity in shipping
    • Maritime Knowledge
    • Offshore
    • Ports
    • Reports
    • Shipping
    • Sustainability
    • Videos
    IMO wishes for further extension of the Black Sea Grain Initiative

    IMO wishes for further extension of the Black Sea Grain Initiative

    Mexican seize cargo port managed by US company

    Mexican seize cargo port managed by US company

    RMI registry flag receives 19th QUALSHIP 21 roster

    RMI registry flag receives 19th QUALSHIP 21 roster

    offshore wind supply chain

    More Norwegian companies invest in offshore wind

  • Columns
    WSC: Minimising accidents is at the top of liner shipping’s agenda

    WSC: Minimising accidents is at the top of liner shipping’s agenda

    technology

    How a joined-up approach to technology drives people performance

    SCMA: Maritime arbitration is expected to rise in prominence

    SCMA: Maritime arbitration is expected to rise in prominence

    Trending Tags

    • Career Paths
    • Industry Voices
    • Maripedia
    • Maritime History
    • Resilience
    • Seafarers Stories
    • SeaSense
  • Events
  • Plus
No Result
View All Result
  • Home
  • Safety
    • All
    • Accidents
    • Alerts
    • Loss Prevention
    • Maritime Health
    • Regulation
    • Safety
    • Seafarers
    • Security
    lessons learned

    Lessons learned: Safety warning issued about the hazards of flexible hose installations

    amsa mlc

    HRAS urges the Australian Government to reinforce its national legislative on seafarer welfare

    Multiple boats on fire at Seattle Marina

    Multiple boats on fire at Seattle Marina

    ReCAAP ISCReCAAP ISC One incident

    ReCAAP ISC: One incident of armed robbery 14 – 20 Mar

  • SEAFiT
    • All
    • Intellectual
    • Mental
    • Physical
    • Social
    • Spiritual
    Why sleep and mental health go hand-in-hand

    Why sleep and mental health go hand-in-hand

    Life coaching tips: How to maintain a good work-life balance

    Life coaching tips: How to maintain a good work-life balance

    Wabi sabi

    Wabi Sabi: Imperfection makes perfection at work

    sexual abuse

    Sexual abuse at sea: Where we stand

  • Green
    • All
    • Arctic
    • Ballast
    • Emissions
    • Fuels
    • Green Shipping
    • Pollution
    • Ship Recycling
    • Technology
    K Line adds kite on vessel to lower emissions

    K Line adds kite on vessel to lower emissions

    training maritime decarbonization

    Six companies join forces to build methanol tanker

    ClassNK answers FAQs on the EU-ETS

    ClassNK answers FAQs on the EU-ETS

    EU green shipping

    EU agrees to 2% mandate for green shipping fuels by 2025

  • Smart
    • All
    • Connectivity
    • Cyber Security
    • E-navigation
    • Energy Efficiency
    • Maritime Software
    • Smart
    NAPA: Simulation software aids in predicting CII

    NAPA: Simulation software aids in predicting CII

    Canada, UK join forces for R&D digital project on decarbonization

    Canada, UK join forces for R&D digital project on decarbonization

    technology

    How a joined-up approach to technology drives people performance

    New smart project aims to improve maritime logistics

    New smart project aims to improve maritime logistics

  • Risk
    • All
    • CIC
    • Detentions
    • Fines
    • PSC Case Studies
    • PSC Focus
    • Vetting
    australia sea mines

    AMSA imposes 90-day ban on Dutch vessel

    Singapore

    Eco Spark arrested in Singapore

    Liberia

    Liberia: key guidance for machinery space deficiencies

    orange county oil spill fines

    Taiwan’s Wan Hai Lines to pay $950,000 in civil penalties

  • Others
    • All
    • Diversity in shipping
    • Maritime Knowledge
    • Offshore
    • Ports
    • Reports
    • Shipping
    • Sustainability
    • Videos
    IMO wishes for further extension of the Black Sea Grain Initiative

    IMO wishes for further extension of the Black Sea Grain Initiative

    Mexican seize cargo port managed by US company

    Mexican seize cargo port managed by US company

    RMI registry flag receives 19th QUALSHIP 21 roster

    RMI registry flag receives 19th QUALSHIP 21 roster

    offshore wind supply chain

    More Norwegian companies invest in offshore wind

  • Columns
    WSC: Minimising accidents is at the top of liner shipping’s agenda

    WSC: Minimising accidents is at the top of liner shipping’s agenda

    technology

    How a joined-up approach to technology drives people performance

    SCMA: Maritime arbitration is expected to rise in prominence

    SCMA: Maritime arbitration is expected to rise in prominence

    Trending Tags

    • Career Paths
    • Industry Voices
    • Maripedia
    • Maritime History
    • Resilience
    • Seafarers Stories
    • SeaSense
  • Events
  • Plus
No Result
View All Result
SAFETY4SEA

Case study: Mooring line failure onboard

by The Editorial Team
December 3, 2019
in Loss Prevention, Maritime Knowledge
captain

Above image is used for illustration purposes only / Credit: Shutterstock

FacebookTwitterEmailLinkedin

A large LNG carrier was docked in an LNG terminal in UK. The 345.30m LOA carrier was moored with a total number of 20 lines (high modulus polyethylene ropes) following the ‘3-2-3-2 fore and aft’ rule. The vessel had 22 lines on board (as per manufacturer’s requirements) to be used during mooring operations of 44mm diameter Steelite Superline Xtra high modulus polyethylene (HMPE) with a specified minimum breaking load (MBL) of 137t.

 

Credit: UK MAIB Report 13/2017

While vessel was moored, a line parted and injured 3rd Officer who suffered severe injuries.  When the line parted the wind was westerly at about 32kts and the tidal stream was ebbing to the west at 0.6kt (the tidal range was 4m). The air temperature was about 6°C, it was raining and it was dark. These conditions were similar to those predicted in the local inshore weather forecasts. The prevailing wind was reaching max strength with extended gusts.  One of the fore spring lines parted due to tensile overload even though the load being applied to the line at the time was less than a quarter of its specified minimum breaking load.

But how did an inspected mooring rope part despite the monitoring and inspections of same as per Company’s requirements? All mooring lines had been subjected to regular visual inspections by the ship’s crew and the rope manufacturer’s representatives, and their condition had always been assessed to be good. The PMS required 4-monthly inspections of each rope. To do this, the ropes were removed from the winch drums and visually inspected over their entire length. The PMS provided information on types of damage to look for and guidance on rope rejection or discard criteria.

RelatedNews

Lessons learned: Safety warning issued about the hazards of flexible hose installations

NTSB Investigation: Breakaway of moored mobile offshore drilling unit and subsequent collision

In order to prolong the life of the mooring ropes, the PMS recommended that:

  • Ropes normally used as ‘Springs’ should be rotated with other ropes every 2 years; and,
  • All ropes should be end-for-ended every 4 years.

The maintenance undertaken and observations made during the rope inspections were recorded in the vessel’s electronic PMS database. In addition, records were maintained of the air temperatures and wind speeds at the terminals while the vessel was moored.

Jacked rope construction

Accordingly, the main issue with such rope inspection is that jacketed design prevented the identification of key discard criteria such as broken yarns and fused fibres. In addition, other high modulus synthetic fibre rope condition degradation phenomena, such as creep, cannot readily be assessed without physically dissecting the rope.

GET THE SAFETY4SEA IN YOUR INBOX!

So were these ropes adequate for use on board such vessel in respect of size and operational envelop? As the official investigation concluded, the arrangement of mooring decks on board contributed significantly to the rope’s loss of strength and the officer being injured; the mooring lines used on board vessel (and similar vessels in the same fleet) were not suitable for the application; and the primary influences on rope degradation and failure modes were not fully understood by the user.

Close visual examination of the break site identified that the yarn fibres had suffered localised fusing and hardening, and that the failure had been caused by tensile overload. Away from the break site, the rope appeared to be in generally good condition.

Key feedback

A technical Company authorized to provide failure analysis based on broken line samples. The outcome of this analysis after investigation and laboratory measurements was that the inner part of jacked rope (3-strands) reveled yarn kinks which were effective to failure.

Credit: UK MAIB Report 13/2017

Based on the results of break load tests, and taking the number of failed yarns discovered in damaged rope into account, the authorized Company estimated that the residual strength of the rope samples tested could have been as low as 61.6t. This was about 45% of its specified MBL (137t).

Additionally, the painting of snap back areas had also contributed to the accident. As per previous Best Practice Guidance, areas near mooring points should be marked for the Snap-Back hazard.

Credit: UK Club / Back hazard area at the time of accident – No longer valid best Practice marking of snap

However, this practice created a false sense of safety in case the seafarer was not on or next to yellow marked area. Considering that the reaction of a broken line under tension practically is unknown and difficult to be predicted, such marking of “danger areas” is not actually a safety practice.

Lessons learned

Consequently, this incident and several other similar led to the revision of some of the mooring practices:

  1. The OCIMF Guidance for Mooring was revised to MEG-4 in order to address similar issues; new definitions were introduced and new guidance was provided in respect of purchasing, using, inspecting and retiring mooring lines.
  2. The practice regarding snap back zones was also revised; the markings on the deck were removed and replaced with the generic warning that all mooring decks are subject to snap-back hazard (Image 4)
  3. Effective procedures are now required to be inforce on board vessels in order to minimize incidents during mooring operations. A comprehensive and detailed risk assessment should be undertaken prior conducting such operations.
  4. An effective tool box meeting is to be conducted also in order to provide guidance on the established mooring plan taking into consideration: Vessel’s arrangements and equipment; Terminal or port arrangements and ; Prevailing and predicted environmental conditions
  5. Lastly, all mooring stations should be under the control and monitoring of a competent officer who should use a Stop work procedure or authorization in order to protect fellow seafarers and vessel’s equipment from unpleasant situations during mooring.
New developed approach to mark snap back danger areas / Credit: UK Club

 

MOORING PROCEDURES: Read in this series

safe mooring

6 tips for safe mooring operations

December 13, 2019
captain

Case study: Mooring line failure onboard

December 3, 2019
Brazil

Mooring Equipment Guidelines: Updates and new terms

December 3, 2019
mooring injury

Mooring Incidents: Assessing common pitfalls and key challenges

December 2, 2019
hong kong lessons learned

Do’s and don’ts when dragging anchor

November 19, 2019
captain

Safe Mooring: Key challenges

October 9, 2019
killed mooring line

INTERTANKO publishes guide on Mooring System Management Plans and Line Management Plans

March 15, 2019
captain

OCIMF MEG 4 Review: Mooring lines issues in the spotlight

November 26, 2018
mooring

Procedures: Mooring line handling tips

August 23, 2018
killed mooring line

OCIMF Mooring Equipment Guidelines (MEG4) – An Update

August 6, 2018
Tags: lessons learnedmooringMooring Procedures cmsm

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Recommended

lessons learned

Lessons learned: Safety warning issued about the hazards of flexible hose installations

March 23, 2023
IMO wishes for further extension of the Black Sea Grain Initiative

IMO wishes for further extension of the Black Sea Grain Initiative

March 23, 2023

SEAFiT Poll

What is the biggest obstacle for the social life onboard?

Stay tuned for the results!

MARITIME EVENTS

Explore

  • Safety
  • Green
  • Smart
  • Risk
  • Others
  • Events
  • Plus

Useful Links

  • About
  • Disclaimer
  • Editorial Policies
  • Advertising
  • Contact

RISK4SEA Facts

Did you know that Manager Base matters for 2020? Hong Kong-based managers with General Cargo had approximately 52% more on Detention Rate than the global average.

Learn more risk4sea.com

© 2021 SAFETY4SEA

No Result
View All Result
  • Safety
    • Alerts
    • Accidents
    • Loss Prevention
    • Maritime Health
    • Regulation
    • Safety
    • Seafarers
    • Security
  • Green
    • Arctic
    • Ballast
    • Emissions
    • Fuels
    • Green Shipping
    • Pollution
    • Ship Recycling
    • Technology
  • Smart
    • Connectivity
    • Cyber Security
    • E-navigation
    • Energy Efficiency
    • Maritime Software
    • Smart
  • Risk
    • CIC
    • Detentions
    • Fines
    • PSC Focus
    • Vetting
  • Others
    • Diversity in shipping
    • Maritime Knowledge
    • Offshore
    • Ports
    • Reports
    • Shipping
    • Sustainability
    • Videos
  • Columns
    • Opinions
    • Career Paths
    • Industry Voices
    • Maripedia
    • Maritime History
    • Seafarers Stories
    • SeaSense
  • Events
  • Plus

© 2021 SAFETY4SEA

This website uses cookies. By continuing to use this website you are giving consent to cookies being used. Visit our Disclaimer.