With reference to a recent ILO notice on the health hazards from asbestos:

Asbestos was widely used in ship construction and machinery before its ban. It may still be found in:

• Insulation of hot surfaces: lagging around exhaust pipes, steam pipes, boiler casings, exhaust gas boilers, and cylinder jackets.
• Fire-resisting and acoustic insulation in bulkheads, decks and accommodation bulkheads (fire stops, fire doors linings).
• Old fire blankets and some firefighting/thermal protective material.
• Gaskets and packing in old valves, pumps, flanges and gland packing (behind pipe joints on tankers/steam ships).
• Brake linings of winches, windlasses and clutches; clutch linings.
• Ceiling tiles, floor tiles and mastic in accommodation.
• Electrical cable fire-resisting insulation (older vessels), and cable sleaving.
• Boiler and funnel lagging, and in the internal cladding of older incinerators.
• Packing/glands on older cargo and machinery, pipe insulation, and sometimes in the earlier fire-fighting suites (fire suits).

New ships since roughly the 1980s (and under SOLAS and the new-build IHM/Hong Kong Convention provisions) are prohibited from using asbestos; existing installations may remain in older tonnage, so the danger remains during repair, alteration and demolition.

• Inhalation of asbestos fibres (especially amphibole types such as crocidolite/blue asbestos and amosite/brown, and chrysotile/white) can cause:
• Asbestosis: progressive, irreversible fibrosis (scarring) of the lungs causing breathlessness and reduced lung function.
• Lung cancer: asbestos is a confirmed human carcinogen.
• Mesothelioma: a rare and aggressive cancer of the pleura (lining of the lungs) or peritoneum, almost exclusively caused by asbestos, with a long latent period (20-50 years) after exposure.
• Other asbestos-related disease: thickening/plaques of the pleura, laryngeal and ovarian cancers.
• There is no safe threshold; the risk increases with cumulative dose, and smoking multiplies the lung-cancer risk.
• Because fibres become airborne when material is disturbed (cutting, drilling, grinding, breaking lagging), the danger is acute during repair and demolition operations.
• Symptoms may not appear for many years after exposure.

• Identify the material before work: consult the ship's asbestos register / IHM (Part I) and survey results to locate asbestos-containing material (ACM); treat any unidentifiable old insulation as presumed ACM.
• Do not disturb ACM unless absolutely necessary; if an asbestos-containing pipe insulation is damaged, wet it down and limit access to the area; isolate the work area and warn all personnel.
• Use a competent, trained team: perform emergency repairs by adopting minimum-disturbance techniques; only trained persons with the required respiratory protective equipment (RPE, e.g. FFP3 masks or air-supplied respirators) and protective clothing should handle ACM.
• Wet methods: damp the material to suppress dust; do not use power tools that generate dust; use manual tools where feasible; clean up with damp cloths/wipes and a HEPA vacuum, not dry sweeping.
• Ventilation and segregation: seal off the repair area with plastic sheeting, keep hatches/doors closed, maintain negative pressure/adequate ventilation, and post warning signs.
• Decontamination: personnel remove contaminated clothing before leaving the area; use designated decontamination; dispose of ACM waste in sealed, labelled bags/containers as hazardous waste for proper shore disposal.
• Monitoring and records: if fibres could be released, arrange air monitoring; record the work in the ship's asbestos/IHM records and inform the shipowner/flag so a proper asbestos remediation company can complete permanent removal later.
• Medical and reporting: report any exposure to the shipowner and to medical personnel; take appropriate medical surveillance (such as respiratory checks) as advised under national OSH law.