QUESTION 8.3.11

Non-inert tank cleaning

Oil, ChemicalInterview - Deck Rating, Cargo Control Room, Main Deck

What is being checked

The inspector is checking whether the vessel's arrangements for tank cleaning on an oil or chemical tank that is not inerted are planned, understood and executed using vessel-specific limits, verified line-up, effective communication and traceable records.

Ready onboard

0/6 complete

PROCEDUREThe vessel procedure defines responsibility, sequence, stop criteria and flammability assessment, ventilation, gas testing, static precautions, washing-machine control, temperature, water quality and suspension criteria.PLANThe current plan uses actual cargo, tank, terminal and equipment information and addresses flammability assessment, ventilation, gas testing, static precautions, washing-machine control, temperature, water quality and suspension criteria.LINE-UPTwo competent persons independently verify the critical liquid, vapour, inert-gas and venting path before transfer or system operation.TEAMThe responsible officers and ratings understand their station, communication method, monitoring duty and authority to stop.EVIDENCERecords reconcile the plan with tank-cleaning plan, atmosphere log, equipment checks, deck log and responsible-officer rounds.ABNORMAL RESPONSEThe procedure gives immediate actions for entry into the flammable range, static discharge, steam injection, ungrounded machine, poor ventilation or unmonitored atmosphere.

Practice questions

Answer aloud, then open the preparation point.

1What are the critical controls for tank cleaning on an oil or chemical tank that is not inerted?

Explain the vessel-specific sequence, limits and safeguards for flammability assessment, ventilation, gas testing, static precautions, washing-machine control, temperature, water quality and suspension criteria.

2How was the line-up independently verified?

Identify both verifiers, the physical route checked, valve-position confirmation and the record completed before starting.

3What conditions require the operation to stop?

Stop for loss of communication, unexpected pressure or level, leakage, alarm, incorrect line-up or any of these specific failures: entry into the flammable range, static discharge, steam injection, ungrounded machine, poor ventilation or unmonitored atmosphere.

4Show the most recent complete operation.

Trace the plan through tank-cleaning plan, atmosphere log, equipment checks, deck log and responsible-officer rounds, including any deviation and its authorisation.

5What is the first response to an abnormal condition?

Stop or stabilise the operation, raise the alarm, isolate the source where safe, verify tank and system condition and coordinate with the terminal and Master.

Where an observation may arise

PROCEDURE GAP

The vessel procedure did not adequately address flammability assessment, ventilation, gas testing, static precautions, washing-machine control, temperature, water quality and suspension criteria.

GENERIC PLAN

The plan was copied or did not reflect the actual cargo, tank condition, terminal limits or equipment status.

LINE-UP ERROR

A critical valve or connection was not independently checked, or the recorded position conflicted with the physical system.

KNOWLEDGE GAP

Responsible personnel could not explain their limits, monitoring duty, communications or stop-work authority.

RECORD CONFLICT

The plan, log or checklist could not be reconciled with tank-cleaning plan, atmosphere log, equipment checks, deck log and responsible-officer rounds.

ABNORMALITY UNCONTROLLED

The response did not adequately control entry into the flammable range, static discharge, steam injection, ungrounded machine, poor ventilation or unmonitored atmosphere.

Master's practical note

Use the latest real operation, not a model checklist. Follow one critical parameter from the agreed plan to the CCR display, deck condition and final record.

Equipment boundary and references

Equipment boundary: Apply the vessel's approved cargo manuals, cargo-specific data, terminal agreement and company limits. Do not operate cargo equipment solely to demonstrate it during an inspection.

References

OCIMF SIRE 2.0 Question Library Part 2, Version 1.0, Question 8.3.11
OCIMF ISGOTT, Sixth Edition
ICS Tanker Safety Guide (Chemicals)

Last reviewed: 2026-09-14