Rapport d’enquête sur la sécurité du transport maritime M19C0403

Le présent rapport conclut l’enquête du Bureau de la sécurité des transports du Canada sur cet événement. Le Bureau a autorisé la publication de ce rapport le 28 septembre 2022. Le rapport a été officiellement publié le 15 novembre 2022.

Annexe A – Lieu de l’événement

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Source : Carte 14848 de la National Oceanic and Atmospheric Administration, avec annotations du BST; image en médaillon : Google Earth, avec annotations du BST

Annexe B – Texte de la feuille d’instructions plastifiée au poste de libération du CO₂ à distance du Tecumseh, sur le pont C (en anglais seulement)

Source : Lower Lakes Towing Ltd.

Annexe C – Rôle d’appel du Tecumseh (rôle d’appel d’urgence)

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Source: Lower Lakes Towing Ltd.

The investigation determined that the fire on board the Tecumseh originated on the port main engine after a flexible fuel hose assembly supplying fuel to the main engine failed. The analysis will examine  engine room maintenance, the effectiveness of the vessel’s structural fire protection and emergency equipment, and the decision to re-enter the engine room after the fire had been initially suppressed by the carbon dioxide (CO₂) fixed fire suppression system. The analysis will also look at Lower Lakes Towing Ltd.’s (LLT) safety management system (SMS), the fire response by external resources, and the value of voyage data recorders.

2.1 Engine room maintenance

Considering the critical function of propulsion machinery to the safety of a vessel and its crew, it is essential that engine room equipment and systems be well maintained and that engine room practices minimize risk. The failure of the engines or other machinery or components in the engine room may pose significant safety hazards and, in some cases, create fire risks if these failures occur near ignition sources or flammable materials.

The investigation identified a number of issues related to the condition of the main engines on the Tecumseh. In 2019, prior to the occurrence, both main engines had ongoing issues with leaks in and failures of the fuel oil supply and return hoses, with turbocharger efficiency, and with failures of the hard piping for the fuel oil system, among other things. Three cylinder units and a fuel oil supply rail had also failed. The back pressure regulating valve on the fuel supply system was no longer operating automatically, which was causing pressure pulses in the fuel system. Post-occurrence, the datum positions for the fuel rack indexes on both the port and starboard main engines were found to be adjusted beyond the manufacturer-recommended settings in order to minimize the impact of differences in peak cylinder pressures and exhaust gas temperatures. Finally, it was noted that engines of the same model as that fitted on the Tecumseh had a history of problems with vibration, which could cause short gear train life, engine leaks, and component fatigue. 

The fuel hose assembly that failed in this occurrence was of unknown origin. As a result, there was no way to know

• who had manufactured the fuel hose assembly and whether this was a qualified individual or company,
• when the fuel hose assembly had originally been manufactured and what its working lifespan was,
• whether the materials being used to manufacture the fuel hose assembly were new or used, and
• whether the fuel hose assembly met the standards required for this fuel system.

Without this information, it was not possible to validate whether the fuel hose assembly was of adequate integrity for the safety-critical job it was doing.

A robust SMS, inspections, and audits are potential defences to mitigate the risk of substandard components being used for safety-critical applications. An SMS may have documentation requirements relating to the origin of a component, testing requirements to ensure that the component is adequate for the application in which it is being used, and inspection and maintenance schedules to ensure the integrity of the component while in use.

The investigation found that the SMS had no guidance with respect to documentation, testing, or inspection and maintenance schedules to ensure that the fuel hose assemblies on the main engines were of adequate integrity and remained in working condition. The investigation also found that although Lloyd’s Register had conducted a classification survey on the vessel 24 days before the occurrence, the survey had not identified any issues with the fuel hose assemblies despite a class rule requiring that these assemblies be prototype-tested.

Although the Tecumseh had a computerized planned-maintenance system to keep track of maintenance schedules and to monitor equipment performance, records of periodic performance monitoring of the main engines were incomplete. The engine room crew had recorded various technical issues related to the engine in shipboard documentation and, with the limited resources that they had available, had made attempts to address them. In some cases, they had requested assistance with repairs; in other cases, they had developed workarounds. Some of the requests for shore-based maintenance support had not been answered, and so those maintenance issues had gone unresolved.

2.2 Effectiveness of structural fire protection and emergency equipment

Given that shipboard fires can threaten life and cause severe damage to the vessel and the environment, it is important that structural fire protection and emergency equipment on board be kept in good working order. In this occurrence, the investigation identified issues associated with the vessel’s structural fire protection (engine control room [ECR] boundaries, ventilation fire dampers, and engine room access points) and its emergency equipment (emergency fire pump and emergency generator).

2.2.1 Structural fire protection

Fire pattern analysis indicated that the fire originated in the port-forward area of the lower platform around the engine. The separated fuel oil supply line sprayed fuel onto the engine and hot exhaust components, igniting the fuel. Fuel sprayed onto the engine for approximately 5 minutes, until the engine was shut down from the bridge. The fire spread aft along the electrical cable trays, through unsealed penetrations in bulkheads, finally entering the ECR. Only traces of sealant were present at the time of the occurrence, and it is likely that the sealant had been removed and not replaced in 2005 when the auxiliary generators and associated cables were replaced by a previous owner.

As well, although the maintenance opening for the emergency fire pump compartment needed to be sealed shut to maintain structural fire integrity, it was not properly bolted in place using the fitted arrangement. This opening was the fastest way for the crew to access the emergency fire pump compartment for regular inspections and maintenance. Because the maintenance opening was unsealed, smoke entered the emergency fire pump compartment from the engine room and prevented the crew from entering the compartment to troubleshoot the issue with the emergency fire pump. As a result, boundary cooling after the release of the CO₂ into the engine room was delayed by 2 hours because the emergency fire pump was not supplying water to the fire main line.

Defective seals around all 4 of the fire doors between the machinery casing and the accommodations allowed the propagation of smoke into the accommodations. Also, defective seals and securing arrangements on the engine room ventilation flaps and fire dampers may have allowed fresh air to enter the engine room following the release of the CO₂.

These problems with the integrity of the structural fire protection worsened the fire and impaired the crew’s efficiency during the fire response.

2.2.2 Emergency equipment

A vessel’s emergency equipment, including the emergency fire pump and emergency generator, is critical during an engine room fire. The emergency fire pump is the only pump available outside the engine room to supply water to the fire main line and to allow the crew to suppress the fire and carry out boundary cooling. The emergency generator is essential during shipboard emergencies because it supplies power for the emergency fire pump and for lighting so that the crew can respond adequately. Transport Canada has recognized the importance of keeping sufficient reserves in the fuel oil tank for an emergency generator and has regulated a minimum run time to ensure that power from the emergency switchboard is available for the duration of the emergency.

2.2.2.1 Emergency generator

On the Tecumseh, the space above the top of the emergency generator tank was not large enough to accommodate the length of the sounding rod, making the rod hard to remove. Therefore, the crew opted to keep the tank unsealed. This adaptation was made in response to the cumbersome design of the sounding rod. It also led to another adaptation, which was to routinely keep the fuel oil in the emergency generator tank just at over half full to avoid it spilling out the open sounding pipe.

During the fire response, after the emergency generator had been running for about 6 hours, the crew became concerned about the level of fuel oil in the tank. The normal arrangement to transfer fuel oil from the engine room’s diesel oil storage tank could not be used due to the location of the fire, so the crew began manually transferring fuel oil from the forecastle using pails. The crew encountered difficulties refilling the tank with the pails; however, the emergency generator kept running until the vessel was secured at the Morterm Ltd. terminal.

2.2.2.2 Emergency fire pump

In this occurrence, the investigation could not determine why the emergency fire pump on the Tecumseh did not supply water to the fire main line after its remote starting button had been depressed. No indicator or instrument was available to the crew to determine whether the pump’s motor was running, and the pump was neither self-priming nor fitted with a self-priming device. Without a method for self-priming, the pump may have become air-locked when it was started, as air trapped in a centrifugal pump’s casing may prevent water from entering from the suction side even when the pump is installed below the vessel’s waterline. It is also possible that the contactor for the pump’s electrical starter did not engage, which was a problem that the crew had encountered in the past.

Without status indicators and position feedback on the deck C control panel, there was no way for the crew to know the valve positions and the running status of the pump unless they enterered the compartment, and this was not possible due to the accumulation of smoke.

2.3 Decision to re-enter the engine room

CO₂ displaces air and smothers the fire but has limited cooling properties, so Marine Emergency Duties (MED) training^{Footnote 61} teaches participants to wait for the temperature to drop below the auto-ignition point (often 12 to 24 hours) before re-entering an engine room that has been flooded with CO₂.

In this occurrence, after the CO₂ had been released, there was concern that the fire would spread because of the condition of the bilges and possible leaks from the fuel oil piping. After discussion between the chief engineer, master, and shore management, re-entry was approved despite the consequences of introducing fresh air into the compartment while re-entering the engine room and potentially re-igniting the fire.

The third engineer and an engineering assistant were tasked by the chief engineer to enter the engine room. Based on their MED training and their concerns about compromising the effectiveness of the CO₂, they opposed the re-entry. Although informed of these concerns, the chief engineer remained focused on the need to enter the engine room. The memory of an earlier engine room fire, in which re-entering the engine room only 2 hours after CO₂ release had no adverse consequences, was a factor in the chief engineer’s decision making.

The steering gear access hatch and a door were opened during the 20-minute attempt to enter the engine room and get to the bilges.

Because of the vessel’s certification (Near Coastal Voyage Class 1, limited to inland waters Class 1 [LIM IW1]), crew members were exempted from MED refresher requirements. However, the risk of encountering hazards that the MED training covers does not diminish based on the class of voyage alone. In this occurrence, the shore and vessel management personnel relied on MED training that was taken many years before. Their memory of training had likely faded over time and was modifed by later experiences, whereas crew who had undergone recent MED training were able to recognize the hazard of re-ignition.

2.4 Safety management systems

Safety management requires all organizations to be cognizant of the risks involved in their operations and to competently manage those risks. An effective SMS can help to ensure that members at all levels of an organization have the knowledge and the tools to manage risk effectively, as well as the necessary information to make sound decisions in any operating condition, including both routine and emergency operations.

2.4.1 Fire emergency procedures and training

When a fire breaks out on a vessel, a prompt and coordinated firefighting response carried out by trained personnel with appropriate equipment is key to ensuring that the fire is brought under control and extinguished. Fire emergency procedures and related vessel-specific SMS documents, such as emergency checklists, help the crew develop a shared understanding of the emergency response, facilitating the coordination of efforts. Without the support of procedures, masters and senior officers are left to react to all aspects of a fire response while the emergency is occurring.

Whereas procedures support decision making during an emergency, drills help ensure that crucial actions become automatic. They provide an opportunity to practise a variety of emergency responses and ensure that crew members are familiar with available emergency equipment, such as the portable firefighting appliances and their location. Training and practice are particularly important because, during a fire, there is little time to learn how to use rescue and firefighting equipment and the stressful nature of the emergency makes it more difficult to remember the procedures and techniques. The more often drills and training are performed, the more the crucial actions needed in an emergency become automatic and the less interpretation and decision making are required, potentially saving critical seconds.

Realistic-scenario fire drills are an example of the type of practice that can facilitate information retrieval. In emergency situations, crew members rely on experience to make rapid decisions; this is known as “recognition-primed decision making.” Frequent practice, especially when it encompasses a wide range of scenarios, provides a pool of experience to draw on when responding to an emergency. Additionally, when practice sessions include a mixture of procedural knowledge (how to do it) and conceptual knowledge (why are we doing it), skills are better retained and transferred to other situations.^{Footnote 62}

In this occurrence, the investigation identified the following shortcomings of the SMS with regard to fire response:

• The fire training manual on board was not specific to the vessel, and so vessel-specific information was not available for use in training on actual equipment on board, such as the CO₂ system.
• There was no emergency preparedness plan on board to guide the crew in the fire response actions, such as when to close the ventilation flaps and fire dampers.
• The fire control plan had not been updated to show the current state of the vessel. For example, it showed 4 firefighter outfits instead of 2, it did not indicate the location of the foam applicator, and it incorrectly showed the maintenance opening to the emergency fire pump compartment in the engine room as a door.
• The fire emergency procedures did not include provisions for recovery or rescue to back up the firefighting team, nor was equipment provided to do so.
• Although drills were conducted monthly as required, the drill scenarios in 2019 did not simulate a major engine room fire similar to the one encountered in this occurrence.
• The muster list did not include a description of the specific duties assigned to each crew member during an emergency, nor did it include alternate muster stations or substitutes for key positions.
• Some of the crew were not sufficiently familiar with the shipboard firefighting equipment.

Despite these shortcomings in the SMS, the crew on the Tecumseh took a number of the steps required for a successful fire response. There were, however, a few aspects of the fire response that were problematic. While some were directly attributable to the above-mentioned shortcomings in the SMS, others likely related to some combination of shortcomings in training, instructions, and emergency drills for fire response:

• The CO₂ was released before the quick-closing oil and fuel valves were closed and before the engine room was sealed shut, which posed a risk that the one-time system might not work as intended.
• When the crew re-entered the engine room, it was to check if the fire was spreading to the bilge and if so, apply firefighting foam in the bilges using large-capacity foam fire extinguishers in the engine room. However, these extinguishers contained CO₂, not foam, and were unsuitable for use in the bilges.
• The decision to re-enter the engine room was driven by the memory of previous experience instead of recent MED training and drills.
• Some of the ventilation fire dampers and other openings were not closed promptly, and there was a short delay in crew members donning the firefighting outfits because it was not clear which crew members were responsible for these duties.

2.4.2 Hazardous occurrence reporting

When hazardous occurrences and near misses are reported, crew members, shore-side management, and contractors can identify and analyze trends, assess potential hazards and risks, predict maintenance, and continuously improve safety in order to prevent future accidents or incidents. Follow-up of hazardous occurrence reports is required under the International Safety Management (ISM) Code.

Although LLT’s SMS had a hazardous situation reporting process, the repeated hose assembly failures were not recorded in the company’s near-miss/hazard reporting documentation (known as Due Diligence Log statements). Efforts to address the hose assembly failures were focused on mechanical deficiencies rather than the underlying nature of the problem, and limited documentation, resulting from the absence of systematic record-keeping, impeded the company’s ability to analyze maintenance trends and perform effective preventive maintenance. As well, without these failures being reported, it was not possible for internal and external audits to assess the associated risks or carry out a safety-focused investigation to identify the root cause of the failures.

2.5 Fire response by external resources

The fixed CO₂ fire suppression system on board the Tecumseh was a single-use system. Once it had been used, external support was required to contain the fire.

2.5.1 Support from the Port of Windsor

The crews of large commercial vessels consist of a dozen or more professional seafarers duly trained in marine firefighting, and the vessels are equipped with portable firefighting appliances and fixed firefighting systems. However, in some circumstances, they may need to rely on shore-based support to fight shipboard fires. Vessel fires in port can also present a serious hazard to the port and the surrounding area.

Most of Canada’s ports and harbour authorities rely on municipal fire brigades for firefighting support. However, as demonstrated in this occurrence and previous occurrences investigated by the TSB, municipal fire brigades do not always have the proper training or resources to fight shipboard fires. Therefore, the management of these brigades forbids its staff to board a vessel on the basis of occupational health and safety requirements.

The Windsor Port Authority relied on the City of Windsor’s Fire and Rescue Services for firefighting services. However, these services did not receive training for shipboard firefighting. As a consequence, shore-based firefighters did not board the moored vessel but instead provided fire teams from T&T Marine Salvage Inc. (the salvage contractor required by U.S. regulations) with shore-based assistance and support. Such support included boundary cooling from shore, water supplies for the on-board firefighters, and use of a breathing air compressor to refill bottles for the self-contained breathing apparatus.

An international shore connection allows the shipboard fire main line to connect to other water supplies, as standards often vary between vessels and port facilities around the world. Municipal fire brigades serving ports do not always carry an international shore connection to support shipboard firefighting. Neither the Windsor Port Authority nor the City of Windsor’s Fire and Rescue Services carried an international shore connection.

2.5.2 Other support

In this occurrence, because the Detroit fire department’s firefighting vessel was out of service for the winter, the U.S. Coast Guard and the Joint Rescue Coordination Centre sent other small vessels that could provide tug services and support but not firefighting capabilities. Other firefighting support came from T&T Marine Salvage Inc. The first salvage party boarded the vessel approximately 4.5 hours after the fire had been re-ignited, and the second salvage party arrived from Texas more than 3 hours after the vessel had been towed to the Port of Windsor.

2.6 Voyage data recorder

Objective voyage data recorder (VDR) data are invaluable to investigators when they attempt to understand a sequence of events and identify operational problems and human factors.

In this occurrence, the Tecumseh did not have a VDR on board, nor was one required by regulation. Consequently, investigators could not confirm engine orders and the timing of emergency response actions, or gain a complete picture of internal and external communications.

This report concludes the Transportation Safety Board of Canada’s investigation into this occurrence. The Board authorized the release of this report on 28 September 2022. It was officially released on 15 November 2022.

Appendix A – Area of the occurrence

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Source: National Oceanic and Atmospheric Administration chart 14848 with TSB annotations; inset Google Earth with TSB annotation.

Appendix B – Text of laminated instructions at the Tecumseh’s CO₂ remote release station on deck C

Source: Lower Lakes Towing Ltd.

Appendix C – Tecumseh’s muster list (station bill)

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Source: Lower Lakes Towing Ltd.