Marine Digest -Engine room fire safety– LAGGING’S

Incident 1

The duty engineer noticed smoke and fire coming from a main engine turbocharger lagging. The bridge was informed immediately, and the main engine control was transferred to emergency control room.  The vessel maneuvered to emergency anchorage safely. The vessel dropped anchor and engine room crew extinguished the fire.  There were no injuries.

Lessons learnt

• The damaged lagging was removed, and engine was tried out. No leakage was observed from the bellows and the manifolds.
• However, the lagging on the main engine exhaust trunking had been replaced in recent days. The cause was traced to inappropriate material and workmanship in the replacement lagging work.

Incident 2 – Non managed bulk carrier reported an engine room fire. The fire caused damage to machinery components, piping, cables and bulkhead and the engine room was partially flooded. The probable cause of the fire was spraying of leaking hydraulic oil onto an exhaust flange which was not properly insulated . The exposed flange must apparently have reached a temperature above 220°C.

Lesson Learnt

Primary sources of ignition in the engine room include hot exhaust manifolds of engines, boilers and indicator valves of the engines. When flammable liquids leak on, splash over, or are sprayed onto an exposed high temperature surface they can auto-ignite.

SOLAS

For all ships above 500 gross tonnes, SOLAS requires insulation of surfaces with temperature above 220°C, which may be impinged upon as a result of fuel system failure. For ships built after 1st July 1998 this also applies for system failure of lubricating oil, hydraulic oil and thermal oil.

Review by the onboard team

• Check awareness of the engine room staff regarding above SOLAS requirement and various insulation arrangements onboard.
• After maintenance and repairs, attention should be paid to satisfactory re-installation of the insulation, lagging’s.
• Insulation’s and Lagging’s degrade with time due to vibration, repeated heating and cooling down or disassembly and refitting during maintenance. The crew must make sure that high temperature surfaces are always adequately protected when there is a risk of flammable oils being sprayed over the surface.
• Oil soaked lagging’s, rags present a fire risk as they may be ignited by hot work in the vicinity or may self-heat and ignite spontaneously.
• The importance of engine room cleanliness and a general fire safety culture cannot be overemphasized.
• The use of soft or absorbent lagging can create further potential risk, since oil sprayed onto absorbent or soft lagging on a hot exhaust can eventually ignite.
• Oil resistant lagging’s are commercially available. Whilst these are not perfect, they do afford some protection from oil spray or leaks. These oil-resistant lagging types have a silver facing to protect against flammable liquids.
• Good quality and reliable material lagging’s to be used onboard. Substandard material to be returned and not to be used

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