IHM Maintenance

Inventory of Hazardous Materials maintenance

An Inventory of Hazardous Materials (IHM) is a living vessel record, not a one-time newbuilding report. Part I must be maintained as equipment, coatings, insulation, machinery, cables, gaskets, and other components are installed, removed, or replaced. Effective maintenance links purchasing evidence and supplier declarations to vessel locations, quantities, thresholds, and revision history so the inventory remains credible at renewal survey and recycling.

Regulatory context

The Hong Kong International Convention for the Safe and Environmentally Sound Recycling of Ships entered into force on 26 June 2025. The EU Ship Recycling Regulation also imposes IHM requirements on ships within its scope. Application depends on flag, ship type, tonnage, trading pattern, and exclusions. Class societies and authorised hazardous-material experts may be involved in survey and certification. The owner should confirm the governing regime and certificate route for the vessel.

Typical maintenance scope

• Review the approved IHM, maintenance procedure, change log, purchasing workflow, and outstanding evidence
• Screen material declarations and supplier declarations of conformity for equipment and spares
• Map additions, removals, and replacements to the vessel’s structure and equipment
• Conduct onboard visual or sampling checks under a documented sampling and safety plan where evidence is unavailable
• Update Part I, location plans, quantities, evidence register, revision history, and survey-support package

Start with the vessel’s change history

Provide the vessel and IMO number, flag and class, current IHM and certificate, last survey report, maintenance procedure, dry-dock and modification lists, purchasing records, material declarations, drawings, and target survey date. Identify suspect materials and areas with restricted access. Sampling may involve hazardous substances and should use trained personnel, suitable PPE, laboratory chain of custody, and controls that avoid releasing fibres or contaminants. Final certification remains with the authorised survey body.