An Inventory of Hazardous Materials, or IHM, helps identify and locate specified hazardous materials on a ship. Its value extends beyond the final recycling decision. A reliable inventory supports informed maintenance, purchasing and planning throughout the vessel’s service life, provided it is kept aligned with changes on board.

The Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships entered into force on 26 June 2025. Applicability, survey arrangements and transitional provisions must be checked for the vessel, flag and relevant jurisdiction. This article explains a practical preparation process and the evidence owners should organise when discussing green ship recycling consultancy and supervision.

1. Confirm the applicable requirements first

Begin with the ship’s flag, size, use and operating pattern. Confirm whether the Convention applies and whether separate regional or port requirements are relevant. Do not assume that a document prepared for one framework will automatically satisfy every other obligation. Obtain current guidance from the administration or its recognised organisation.

Agree the required survey and certification route, the accepted inventory format and the competence expected of the people preparing it. Establish the programme early enough to coordinate document collection, ship access, sampling and review. A date in a recycling plan is not sufficient if the supporting survey work has not been arranged.

2. Understand the inventory’s different parts

Part I concerns materials contained in the ship’s structure and equipment. It is the central inventory maintained during the operational life of the ship. Before recycling, Parts II and III address operationally generated wastes and stores respectively, in accordance with the applicable requirements and guidance.

Keep the purpose of each record clear

An IHM is not a general list of every chemical ever carried on board, nor is it a replacement for safe maintenance procedures. It identifies the specified materials within its regulatory scope. Personnel working on equipment still need task-specific assessments, product information and the controls required for their work.

3. Build a useful document pack

Collect ship particulars, general arrangement plans, machinery and equipment lists, construction information and records of significant modifications. Add previous inventories, survey findings, relevant drawings and supplier declarations where available. Trace documents to the equipment or area they actually describe; a supplier brochure without a clear product connection offers limited evidence.

Give the preparer access to purchasing and maintenance records as well as the ship. Replacement insulation, coatings, gaskets or electrical components may not match the original build information. Record missing documents openly. Uncertainty should feed into the assessment and survey plan rather than being concealed by an apparently complete spreadsheet.

4. Plan the onboard assessment carefully

For an existing ship, the assessment normally combines document review with an appropriate visual and sampling check plan developed by competent specialists. Identify locations, access requirements, operational restrictions and safety precautions. Coordinate with the master so the work does not create uncontrolled interference with cargo or machinery operations.

Sampling can itself disturb hazardous material. It must be planned and conducted by competent personnel using suitable controls and analytical arrangements. Crew should not improvise sampling to save time. Where access is impossible or evidence remains uncertain, document the limitation and its treatment under the applicable guidance.

5. Make the final inventory traceable

Review whether each entry can be understood by somebody who did not prepare it. Locations should be specific enough to find on board, quantities should have a stated basis and references should connect the entry to supporting evidence. Use consistent equipment names and units throughout the inventory and associated drawings.

Check that laboratory results, observations and supplier information have been interpreted consistently. Separate confirmed findings from assumptions or potential presence as required by the applicable method. A polished document is not necessarily a reliable one; traceability and a clear account of limitations matter more than presentation alone.

6. Establish an onboard maintenance process

Nominate responsibility for maintaining Part I and define how changes are captured. Connect the process to procurement, repair, replacement and modification. Relevant supplier material declarations and declarations of conformity should be requested and retained in line with the applicable inventory guidance and purchasing arrangements.

Consider a routine replacement job: the requisition identifies the item, purchasing requests the necessary evidence, the ship confirms installation and the responsible person reviews the IHM entry. If any link is missing, the inventory can drift away from the physical vessel. Make that workflow manageable rather than dependent on occasional large clean-up exercises.

7. Prepare early for the recycling stage

When recycling becomes a realistic option, coordinate the inventory with the ship-specific recycling planning and the requirements of the selected facility and relevant authorities. Review operationally generated wastes and stores for Parts II and III, and plan how those quantities will be assessed close to delivery.

The IHM informs the ship recycling plan, but the two documents serve different purposes. Review facility authorisation, capability, safety arrangements and environmental controls through an appropriate due diligence process. Commercial negotiations should leave sufficient time for surveys, final documentation and a controlled handover rather than forcing technical decisions at the last moment.

8. Keep evidence available through ownership changes

Retain the inventory, certificates, survey records and supporting documentation in an organised form. Agree access for the ship, shore team and authorised reviewers. During sale or management change, explicitly include the current IHM and the process for continuing its maintenance in the handover package.

After a significant modification, check whether updates or further verification are required. A current issue date alone does not prove that every alteration has been assessed. Ask what changed physically and how the inventory reflects it. That question keeps the focus on the ship rather than the document’s cover page.

Questions to ask before commissioning the work

Discuss these points with competent advisers and the relevant administration. Lilly Maritime’s green ship recycling service overview provides a starting point for defining the consultancy and supervision scope your project requires.