Inventory of Hazardous Materials (IHM): An Overview

The shipping industry relies heavily on a range of materials to construct, maintain, and operate vessels efficiently. However, many of these materials are hazardous to human health and the marine environment. From asbestos in engine room insulation to lead and mercury in paints and batteries, hazardous substances are a necessary reality in shipbuilding. Comprehensive mechanisms for identifying and managing these substances are critical. The Inventory of Hazardous Materials (IHM) is a globally recognised list that supports the safe, responsible, and environmentally sound recycling of ships, while also ensuring safety throughout a vessel’s operational life.

What is IHM?

The Inventory of Hazardous Materials (IHM) is a ship-specific document that lists all hazardous materials onboard that are known to pose risks to human health or the marine environment. It includes details about the location, type, and quantity of hazardous materials contained in the ship structure, systems, and equipment.

The IHM has three parts:

• Part I: Lists dangerous materials that are part of the ship’s structure or equipment, like asbestos in walls, lead in paint, or harmful insulation.

• Part II: Lists waste made during the ship’s operation, like oil residues, chemical leftovers, and sludge from machinery.

• Part III: Lists items stored on board, like spare parts, batteries, cleaning products, and paints that could be hazardous.

Often referred to in earlier guidance as the Green Passport, the IHM is now central to global efforts under the Hong Kong International Convention and the EU Ship Recycling Regulation (EU SRR) to promote environmentally sound ship recycling.

History of IHM and Regulatory Evolution

The concept of the IHM originated in the early 2000s as part of voluntary environmental programmes. However, in May 2009, the International Maritime Organization (IMO) adopted the Hong Kong Convention to formalise this into international law. The Convention aims to protect workers and the environment during ship recycling and throughout the vessel’s lifecycle.

In addition to this, the EU SRR (Regulation No 1257/2013) came into effect in December 2013, establishing stricter requirements for all ships calling at EU ports, not just those flagged under the EU.

The Hong Kong Convention will enter into force on 26 June 2025, 24 months after the entry-into-force conditions were met in June 2023. The EU regulation had previously already set enforceable deadlines, particularly requiring existing ships to comply with IHM requirements by 31 December 2020.

Why is the IHM Important?

The IHM is a cornerstone of ship safety and sustainable operations for several reasons:

• Protecting human health: Ensures that dangerous substances like asbestos and heavy metals are tracked and handled safely.

• Supporting environmentally sound recycling: Guides ship recycling facilities on proper dismantling techniques.

• Compliance with international regulations: Satisfies requirements under the EU SRR and future Hong Kong Convention enforcement.

• Facilitating port entry and trade: Non-compliance can lead to detailed inspections or denial of access to EU ports.

Scope of the IHM

The IHM applies to all ships of 500 gross tonnage and above, flying the flag of an EU member state or calling at EU ports. It covers:

• New ships and existing ships, regardless of whether they are engaged in domestic or international trade.

• The entire operational life of the ship, from construction to decommissioning.

• All parts of the ships, including hull, machinery, electrical systems, insulation, and consumables.

The IHM must be maintained throughout a ship’s life and updated whenever significant changes, repairs, or retrofitting occur. This requires ship owners to integrate IHM updates into their routine ship management processes.

Types of Hazardous Materials Covered

Materials listed in the IHM include, but are not limited to:

• Asbestos: Often used for insulation due to its fire-resistant properties, but extremely hazardous when inhaled.

• Polychlorinated Biphenyls (PCBs): Found in older electrical equipment, paint, and insulation materials; highly toxic and persistent in the environment.

Heavy Metals:

• Lead (in paints, pipes, and batteries)

• Cadmium (in plating, coatings, and plastics)

• Mercury (in thermometers, lighting, switches)

• Chromium VI compounds (used in paints, coatings, and anti-corrosion treatments)

• Ozone-Depleting Substances (ODS): Including CFCS and halons used in refrigeration, air-conditioning, and fire suppression systems.

• Flame Retardants: Such as Hexabromocyclododecane (HBCDD) used in insulation foam, now restricted under EU SRR.

• Perfluorooctane Sulfonic Acid (PFOS): Found in fire-fighting foams, coatings, and cleaning agents; banned or restricted in many jurisdictions.

• Tributyltin (TBT) Compounds: Used in anti-fouling paints to prevent marine growth on hulls; highly toxic to aquatic life.

• Radioactive Substances: May be present in some older navigational equipment or instruments.

• Biocides and Pesticides: Sometimes used in coatings or cargo areas to prevent infestations.

• Oil and Fuel Residues: Including sludges or contaminated materials stored in tanks or machinery.

The substances categorised under IHM Part I (materials in the structure and equipment) must be identified through material declaration and the supplier’s declaration during procurement.

What Are the Benefits of an IHM?

The creation and upkeep of an IHM offer various benefits:

• Operational transparency: A verified IHM helps crew members identify and safely manage hazardous materials onboard.

• Improved lifecycle management: Facilitates smarter decisions regarding repair, maintenance, and procurement.

• Regulatory readiness: Ensures preparedness for onboard verification, audits, and inspections.

• Sustainability: Aligns with CSR initiatives for the environment, helping businesses contribute to global sustainability goals.

IHM for New Ships vs Existing Ships

New ships are required to undergo IHM preparation during the construction phase. This includes:

• Gathering MD and SDoC from Tier 1 suppliers

• Verifying these documents for each part of the vessel

• Compiling the data into a comprehensive IHM

For existing ships, the process is more complex:

• Reviewing manuals, repair logs, and historical procurement data

• Conducting a Visual Sampling Check Plan (VSCP)

• Performing IHM initial surveys with the help of certified professionals

The preparation of an IHM for existing ships can be time-consuming, making early action essential for IHM compliance.

Certifications and Verification

To formalise compliance, ships must obtain:

• International Certificate on Inventory of Hazardous Materials (for ships in operation)

• Recycling Certificate and Ready for Recycling Certificate (for ships headed for dismantling)

These certificates are issued following:

1. IHM preparation by certified professionals

2. Review and approval by Recognised Organisations (ROs)

3. Onboard verification of the IHM

Failure to maintain or present a valid IHM certificate may result in a detailed inspection under IMO guidelines.

What This Means for Seafarers and Shipowners

For seafarers, the IHM enhances safety awareness and handling protocols for potentially hazardous materials. Familiarity with hazardous materials IHM entries ensures proper use of protective gear and minimises risk during maintenance work.

For ship owners, maintaining an updated IHM is not only a regulatory requirement but a way to safeguard operations. The responsibility includes:

• Ensuring that all purchases involving hazardous materials are documented

• Updating records after each maintenance or repair job

• Preparing for IHM renewal surveys

Solutions such as BASSnet assist in maintaining a properly maintained IHM by integrating inventory tracking, document management, and reporting.

Conclusion

The Inventory of Hazardous Materials is more than a checklist—it is a strategic instrument for health, safety, compliance, and sustainability. As enforcement tightens through the EU SRR and eventual ratification of the Hong Kong Convention, early action and systematised IHM development can provide a significant operational advantage.

With hazardous materials unlikely to be entirely removed from shipbuilding in the near future, structured management and verified IHM practices will remain essential to the entire fleet.

Frequently Asked Questions (FAQS)

Q1: Is the IHM mandatory for all ships?
Yes, under the EU SRR, it is mandatory for all ships calling at EU ports, regardless of flag. Under the Hong Kong International Convention, it will apply to all ships once the Convention is in force.

Q2: How long is the IHM certificate valid?
The IHM certificate is valid for up to 5 years, subject to ongoing IHM maintenance and periodic verification.

Q3: What happens if my ship does not comply?
Non-compliance can result in fines, detention, or denial of entry at EU ports.

Q4: What is the role of the Recognised Organisation?
ROs are authorised to approve the IHM, verify data, and issue the international certificate.

Q5: Can domestic ships benefit from an IHM?
Yes. Even though domestic ships may not be legally required to maintain an IHM, doing so improves safety and operational readiness.