Compliance and software for LNG and LPG carriers

What LNG and LPG carrier operators have to comply with

The IGC Code: the ship as built

The International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) has been mandatory under SOLAS chapter VII since 1 July 1986. The revised Code applies to gas carriers whose keels were laid on or after 1 July 2016. Class and flag survey the ship against it. What the Code cannot show is how well the ship is run today, and that is what vetting tests.

SIRE 2.0: the ship as operated

SIRE 2.0 covers oil, chemical and gas tankers, and became the standard OCIMF inspection on 2 September 2024. The inspector observes tasks and questions the crew, comparing what people do and say with what your procedures require. For a gas carrier that means cargo and boil-off management, emergency shutdown testing, gas detection, enclosed space entry and mooring are all judged on demonstrated practice, not on a tidy record. Mooring sits in Section 9 of the question set.

TMSA 3: the office behind the ship

Oil and gas majors use OCIMF's Tanker Management and Self Assessment (TMSA 3) to judge the operator, not just the vessel. Each stage you claim needs objective evidence and KPIs. Mooring has its own element, 6A, covering vessel design, people and the mooring system. Repeated SIRE 2.0 observations on your gas ships will be read against your TMSA submission.

SIGTTO guidance: the ship-shore interface

The Society of International Gas Tanker and Terminal Operators (SIGTTO) publishes the industry's reference guidance for gas carriers and terminals, including the LNG Shipping Suggested Competency Standards (third edition, 2021), Recommendations for Liquefied Gas Carrier Manifolds and Guidance on Gas Carrier and Terminal Gangway Interface. Terminals and charterers often expect operators to show how their training, procedures and ship-shore arrangements reflect SIGTTO recommendations.

CDI for LPG carriers in chemical trades

The Chemical Distribution Institute (CDI) runs an inspection scheme for chemical and LPG tankers, used by chemical companies to vet the ships they charter. Unlike SIRE, a CDI inspection is requested by the ship owner. If your LPG carriers load for chemical shippers, expect to manage CDI and SIRE 2.0 side by side.

Mooring: SOLAS II-1/3-8 and MEG4

Since 1 January 2024, amended SOLAS regulation II-1/3-8 requires every ship to inspect and maintain its mooring equipment, including lines, following IMO's guidelines in MSC.1/Circ.1620. OCIMF's Mooring Equipment Guidelines (MEG4) make Ship Design MBL the reference value for lines, tails, winch brakes and fittings.

Gas carriers carry a hard lesson here. In March 2015 a mooring line on the LNG carrier Zarga parted during berthing at an LNG terminal in the UK and seriously injured an officer. The MAIB investigation (report 13/2017) found the lines were not fit for purpose: the residual strength of the parted line was below its working load limit, and the officer was standing in a snap-back zone that had been considered safe.

Hours of rest through long cargo operations

Gas carrier crews often work through loading, discharge, cool-down and gassing-up in quick succession. MLC 2006 and STCW set the rest limits, and SIRE 2.0 treats hours of rest as a core question, so records that look too perfect attract as much attention as records that show breaches.

Ship-to-ship transfer

When gas cargo moves between ships, the Ship to Ship Transfer Guide for Petroleum, Chemicals and Liquefied Gases applies. CDI, ICS, OCIMF and SIGTTO released its second edition in October 2025, so STS procedures written against the first edition are due for review.

Typical gaps on gas carriers

Published findings on gas carriers keep pointing to the same few areas. They are where a pre-vetting inspection on a gas carrier should look first:

• Fixed gas detection. In US Coast Guard Marine Safety Alert 02-20, Port State Control officers found sensors on LNG carriers reading outside the maker's tolerances, catalytic sensors tested with the wrong span gas, and crews not following their own SMS calibration procedures.
• Emergency shutdown, relief valve settings and water spray. The US Coast Guard's Liquefied Gas Carrier National Center of Expertise has named gas detection, emergency shutdown, maximum allowable relief valve settings (MARVS), deck water spray and electrical issues as the most common deficiencies it finds on gas carriers.
• Mooring lines and snap-back zones. The MAIB's Zarga report found mooring lines that were no longer fit for purpose and a snap-back zone that had wrongly been considered safe.

How Synergetic helps gas carrier operators

Services

• Sailing audits and pre-vetting inspections: a Master Mariner sails with your gas carrier and audits navigation, mooring and cargo practice as it happens, then inspects against SIRE 2.0 before the real inspector does.
• Remote VDR and S-VDR analysis: see how your bridge teams handle pilotage and terminal approaches, without putting an auditor on board.
• TMSA 3 gap assessment: every element tested against objective evidence, then a mock office audit before the oil major's review.
• MEG4 mooring gap analysis and engineering assessment: SDMBL, line design break force, tails, winch brakes and fitting SWL verified, residual strength testing, line parting investigations, mooring plans and TMSA Element 6A reviews.
• SMS revamp: cargo, technical and navigation manuals rewritten as plain, task-based procedures, with each SIRE 2.0 and TMSA 3 requirement traced to the procedure that meets it.
• Incident investigation and shore and onboard training built on your own fleet's evidence.

Marine X7 modules that fit gas carriers

• DigiMoor X7: mooring line management software with ClassNK type approval against SOLAS II-1/3-8, MSC.1/Circ.1620, MEG4, SIRE 2.0 Section 9 and TMSA 3 Element 6A. Its shared ports database shows mooring compatibility before the ship is fixed or arrives, which matters at terminals with their own mooring rules.
• Work-Ship: work and rest hours software approved by ClassNK and IRClass, which alerts ship and shore to non-compliances as they happen during long cargo operations.
• PMS X7: ClassNK approved planned maintenance with critical equipment flagged, so cargo machinery, gas detection and safety systems have a record an inspector can trust.
• PTW X7: permits built for the ship type, the space and the task, which suits gas-dangerous zones and enclosed spaces.
• DMS X7 and HSEQ X7: your SMS mapped to SIRE 2.0 and TMSA 3, and every finding turned into fleet focus areas.

Each module runs on its own, so you can start with the one that fixes today's problem. See the full Marine X7 suite and our approvals and certifications.

Why gas operators work with us

• Master Mariner-led: the people who audit your ship have commanded ships.
• 550+ onboard sailing audits and pre-vetting inspections, and 2,200+ remote VDR analyses.
• 28 SIRE 2.0 and RightShip gap analyses, and 16 TMSA 3 and DryBMS office preparations.
• 70+ ship owners and managers, with 100% client retention.

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