Marine & Offshore

Marine and offshore engineering faces high humidity, salt-spray corrosion and tight space — so insulation must resist moisture, corrosion and be lightweight. Fire divisions must hold under rolling and pitching, and pipe systems must stay serviceable in a corrosive atmosphere. Asbestos-free calcium silicate and ceramic fiber dominate the safety-critical zones.

Marine & Offshore Application Scenarios

• Ship deck fire barriers — rock wool layers prevent fire spread across decks.
• Cabin wall insulation — rock wool and glass wool keep living quarters comfortable.
• Cable-trench fire barriers — rock wool stops cable fires from propagating.
• Ventilation duct lining — glass wool reduces heat loss and noise in ship HVAC.
• Exhaust-pipe heat shields — ceramic fiber jackets rated to 1430 °C cut radiation near personnel.
• Marine boiler & engine piping — ceramic fiber on high-temperature lines withstands long service.
• Fire bulkheads — 100% asbestos-free calcium silicate, salt-spray resistant with high fire rating.
• LPG tank fire layers & power-system insulation — calcium silicate on storage and propulsion systems.

Related Articles

• Rock Wool Marine & Offshore Applications
• Industrial Pipe Insulation Materials

Marine & Offshore Insulation Standards

Marine and offshore insulation is governed as much by certification as by physical performance. A material that passes a factory test means little without the documentary evidence a classification society requires. The framework that governs most new-build and retrofit work is the International Maritime Organization (IMO) regime, reinforced by regional fire classifications.

• SOLAS and the IMO FTP Code — the International Convention for the Safety of Life at Sea sets structural fire-protection requirements, while the IMO Fire Test Procedures Code defines how materials are tested for non-combustibility, smoke and toxicity, and surface flammability.
• A-60 and H-60 fire divisions — A-class divisions are tested on the cellulosic fire curve; H-class divisions use the faster hydrocarbon curve required for oil, gas and offshore areas. A material that passes A-60 is not automatically accepted for H-60.
• EN 13501-1, Class A1 — mineral wool that meets non-combustibility (EN ISO 1182) and gross heat of combustion (EN ISO 1716) is classed A1 non-combustible, the same concept used onshore and accepted for marine fire divisions.
• ASTM E84 and ASTM E119 — widely referenced surface-burning and fire-resistance tests for materials entering North American and dual-certification projects.

We document every marine-duty specification against these tests and recommend confirming class-society type-approval for the specific division and vessel before a bill of materials is finalized.

How to Select Marine Insulation

1. Fix the fire division first. A-60, A-30, H-60 or H-120 is set by the vessel’s fire plan and is a hard constraint, not a preference.
2. Match the service temperature. Rock wool serves reliably to about 650 °C; ceramic fiber carries exhaust and boiler lines up to 1430 °C; calcium silicate and glass wool cover mid-range and accommodation zones.
3. Weigh the environment. Salt spray, condensation and vibration decide whether a hydrophobic blanket, a rigid board or a faced system is the right call.
4. Confirm approvals. Ask for IMO FTP Code evidence and, where required, class-society type-approval or equivalent test reports.
5. Plan the facing and sealing. A non-combustible core still fails if water reaches the cold face; specify metal jacketing and sealed penetrations.

See our rock wool blanket, ceramic fiber blanket and calcium silicate board for the forms most specified into marine and offshore projects.

Offshore and marine systems combine fire safety, cryogenic duty, and corrosion challenges. See how our insulation performs across related sectors:

• Cryogenic insulation for LNG carriers and low-temperature marine lines
• Fire protection for vessels and offshore platform safety
• Pipe insulation for shipboard process and utility piping networks
• Nuclear-grade insulation for marine reactor and defense applications

A-Class Fire Divisions in Practice

Specifiers routinely misread A-class divisions as pure temperature ratings. The suffix (A-0, A-15, A-30, A-60) states how long the insulated side holds the average temperature rise of the unexposed face below the limit while the division is exposed to the standard IMO cellulosic fire curve, which reaches 945 °C after 60 minutes. Every A-class division, regardless of suffix, must also prevent passage of smoke and flame for the full 60-minute test.

The pass criteria behind the suffix are fixed: average temperature rise of the unexposed face ≤139 °C, and no single point, including at a joint or penetration, above 180 °C. That single-point rule is why joints, cable transits and anchor fixings — not just blanket coverage — decide whether an installation passes. See our A-60, A-30 and A-0 marine fire division guide for the full breakdown, and our A-60 thickness walkthrough for how composite thickness translates into test performance.

Compartment-by-Compartment Selection Matrix

The table below condenses common new-build practice into starting points. Final thickness always follows the class-approved division drawing and the fire-test certificate of the exact product, not the generic values here.

For the material standards behind these build-ups, our marine fire insulation materials and standards article cross-references the FTP Code test each product family must pass.