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RightShip Guide

THE DEEPDRAFT · RIGHTSHIP PREPARATION

Sewage-treatment plant and crew familiarity

RISQ 5.27Section 5 · Pollution Prevention and Control

Applicability: Apply the vessel, equipment and operational conditions stated in this entry.

What is being checked

The fitted sewage plant is maintained and its operation understood.

Ready on board

0 / 7 checked

Check the vessel’s actual procedures, equipment and records against these points from RISQ 3.2.

Have engineering officers explain plant operation/maintenance under maker instructions.Inspect the plant, piping, discharge pumps and air blowers for good condition.For the described aerated plant, verify aeration/blower effectiveness using the fine bubbles in the sludge return line identified by the source.Where tablet chlorination is fitted, use sufficient maker-recommended tablets of the proper dimensions, inserted without breaking.Where chemical-injection chlorination is fitted, verify the controlled sodium-hypochlorite dosing arrangement and pump operation.Have crew explain the source-described sewage discharge routes: an approved operating treatment plant, comminuted/disinfected sewage beyond three nautical miles, or untreated holding-tank sewage beyond twelve nautical miles at the prescribed rate; check the actual applicable conditions before any discharge.Check the sewage shore-discharge connection arrangements against the vessel’s approved installation.

Practice questions

Preparation prompts derived from this entry, not an official inspector interview script.

1Do the distance figures alone authorise sewage discharge?

No. The PDF is a summary and also distinguishes treatment and prescribed-rate conditions. Follow the vessel’s approved arrangements and applicable discharge controls.

2Must every plant use chlorine tablets?

No. Apply the installed plant’s approved design and maker instructions. The source discusses both tablet and chemical-pump chlorinators.

Where a finding may arise

Missing evidence, defects or operation inconsistent with the arrangements described above may prevent a satisfactory answer. These are preparation concerns derived from the question, not reported past observations.

Past observations for practice

Anonymised reports, manually reviewed before publication. These are reported experiences, not additional inspection requirements.

No reviewed observations have been added for this entry.

Share an observation for private review

Remove vessel, company and inspector names, report numbers, exact dates and confidential information. Do not paste a complete inspection report.

Source clarification

The PDF’s discharge paragraph is a summary, not a complete operational permission or account of local restrictions. Its aeration/chlorinator description should be applied to the fitted design, not treated as a requirement to retrofit a different approved plant.

References and source status

RightShip Inspection Ship Questionnaire, November 2025, version 3.2. Section 5, page 81, reference 5.27.

The explanation, checklist and practice answer derive from the supplied questionnaire. Reported observations are separately contributed and manually reviewed; they are not official RISQ guidance.

Independent DeepDraft preparation guide, based on the supplied RISQ 3.2 questionnaire. Not an official RightShip product or inspection report.