QUESTION 10.6.2

Low-flashpoint-fuel bunkering ESD system

Oil, Chemical, LPGCargo Manifold

What is being checked

The inspector is checking whether ship and bunker-source ESD functions, communications and shutdown links stop transfer and isolate fuel safely when a hazardous condition occurs.

Ready onboard

0/6 complete

CAUSE AND EFFECTThe approved matrix identifies manual trips, gas detection, fire, high level, loss of power or communication and resulting valve or pump actions.SHIP-SHORE LINKThe compatible ESD link and backup communication are connected, tested and agreed before transfer.MANUAL POINTSEmergency-stop stations are labelled, accessible and protected from accidental operation.FUNCTION TESTPre-transfer testing proves signal exchange, pump stop, valve closure, alarms and reset under the agreed sequence.CLOSING TIMEValve closure and transfer shutdown avoid unacceptable pressure surge in the liquid line.RESET CONTROLRestart occurs only after cause identification, area verification and joint authorisation.

Practice questions

Answer aloud, then open the preparation point.

1What conditions automatically activate ESD?

Use the vessel cause-and-effect matrix and identify the actual gas, fire, level, power and link failures configured.

2What happens on the bunker vessel or terminal when you press ESD?

Explain the tested linked response, including remote pump stop, valve actions and communications.

3How is pressure surge controlled?

Coordinate valve closing time, pump trip and transfer-system design within the approved compatibility study.

4Can ESD be reset immediately after a false alarm?

No. Identify the initiating cause, confirm safe conditions and obtain ship-shore agreement before controlled reset and restart.

5What if the primary ESD link is incompatible?

Use only an approved alternative established by the compatibility and risk assessment; do not begin with an untested improvised link.

Where an observation may arise

LINK UNTESTED

Transfer starts without proving both sides of the ESD connection.

CAUSE UNKNOWN

Crew cannot explain automatic initiators and resulting actions.

MANUAL ACCESS

An ESD point is blocked, unlabelled or defective.

SURGE RISK

Closing sequence or time is incompatible with the transfer arrangement.

UNCONTROLLED RESET

The system is reset without determining the cause or joint approval.

Master's practical note

Require both sides to state what will move when ESD is activated. A successful lamp test is not proof that the remote pump and isolation valves will respond together.

Equipment boundary and references

Equipment boundary: This applies only where the scoped vessel uses LNG or another low-flashpoint fuel. ESD compatibility and closing-time criteria must follow the approved ship and supplier transfer design.

References

OCIMF SIRE 2.0 Question Library Part 2, Version 1.0, Question 10.6.2
IGF Code Part A-1 chapters 8 and 15
ISO 20519
SGMF LNG bunkering guidance
ISO 21593 where applicable

Last reviewed: 2026-09-10