Isolated Fire Detection Section on a Ro-Ro Cargo Ship
A 2010-built 25,000 GT ro-ro cargo ship has an accommodation fire-detection system with 24 sections. During a port State control inspection, the fire control panel shows section 12 isolated. The label says 'false alarm - steam leak'. Section 12 covers 14 crew cabins and a store room converted from a cabin. The officer on watch explains that the section was isolated three days ago because a detector kept alarming; no fire patrol has been arranged and the bridge has not been informed in writing. In the store room, a steel shelving unit stands 150 mm below the ceiling and partly screens the detector. The detector's indicator lamp cannot be seen from the doorway. The fixed CO2 system for the machinery space has a pre-discharge alarm, but the inspection finds that the alarm is not audible in the engine room workshop when the engine room door is closed. The ship is loading trailers and is scheduled to sail in eight hours.
1. Assess the isolated fire-detection section: what does SOLAS II-2 require, and what should the inspector do?
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A fire-detection section may be isolated for maintenance, but only for the shortest practicable time, with the isolation clearly indicated at the control panel, recorded, and compensated for by other measures. Three days of isolation in a section covering 14 crew cabins, with no fire patrol and no written notification to the bridge, is not acceptable. The accommodation is occupied and the risk is highest at night, when sleeping crew may not smell smoke.
The inspector should require the section to be restored before departure or, if the faulty detector cannot be repaired immediately, require documented compensatory measures. Those measures would normally include a fire patrol at defined intervals through the affected cabins and store room, a temporary means of detection where practicable, a clear instruction to the bridge watch, and a record of when the isolation began and when it will end. The inspector should also check whether the same section has been isolated repeatedly, because that would point to an unresolved maintenance problem rather than a one-off fault.
2. Evaluate the store-room detector installation and the CO2 pre-discharge alarm audibility.
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The store-room detector is not effectively installed. A shelving unit 150 mm below the ceiling can delay smoke reaching the detector, and the obscured indicator lamp makes local confirmation difficult. The shelving should be relocated or the detector repositioned so that it is clear of obstructions, and the indicator should be visible from the access or repeated remotely. This is a detection-performance issue, not a housekeeping detail.
The CO2 pre-discharge alarm must be audible throughout the protected machinery space before the gas is released. If it cannot be heard in the workshop with the engine room door closed, a person working there may receive no warning. The ship should fit an additional sounder or correct the existing alarm so that the warning is effective in all parts of the space. The alarm should also be distinct from other alarms and be tested with the ventilation and shutdown arrangements as part of the fixed-system checks.
3. What records and follow-up should the master establish after these findings?
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The master should establish a fire-detection isolation log showing the section, reason, time and date, compensatory measures, and restoration. The faulty detector should have a defect record and a planned repair date. The CO2 alarm should have a test record showing audibility in the machinery space, including the workshop, and any additional sounder should be added to the maintenance schedule.
Follow-up should include a review of why the section remained isolated for three days without bridge notification, and whether the safety management system requires a formal risk assessment for taking detection out of service. The port State control corrective-action report should be supported by the actual test results, not just a statement that the defects have been rectified.