The Transportation Safety Board of Canada (TSB) has issued a safety concern regarding insufficient crew knowledge on how to properly use carbon dioxide (CO2) fixed fire suppression systems following the investigation into the sinking of the fishing vessel Atlantic Destiny.
With 31 crew on board, the 39.2-metre Atlantic Destiny, operated by Ocean Choice International, left Riverport, Nova Scotia on Feb. 17, 2021 for a 21-day scallop-fishing trip to the fishing grounds near Georges Bank.
It was day 13 (March 2) of the fishing trip when the incident at sea began to unfold. The Atlantic Destiny was about 120 nautical miles south of Yarmouth. Fishing operations were suspended due to the weather and most of the crew were off duty. The vessel was proceeding at reduced speed, with the controllable-pitch propeller set to approximately 40 per cent.
Then, a catastrophic engine failure occurred. The shaft generators and associated machinery exploded, causing a fire and damage that led to flooding in the engine room. Everyone was evacuated by search and rescue authorities and the following day, the Atlantic Destiny sank.
The investigation found that the automatic and manual activation of the engine safety system failed to prevent the engine speed from increasing beyond the design limits of the engine, causing a catastrophic failure and subsequent fire.
The crew used the engine room’s fixed fire suppression system, which releases a heavy blanket of CO2 that displaces air and reduces the oxygen level to a point where combustion cannot occur when the space is properly sealed. However, they re-entered the sealed space on several occasions to investigate the sound of water coming from the engine room and to access the auxiliary generator. These actions re-introduced oxygen into the space, reducing the effectiveness of the suppression system and as a consequence the fire re-ignited.
Although crew members followed documented procedures for use of the CO2 fixed fire suppression system, they were unaware of the need to wait for the space to cool before re-entering.
“Proper sealing of the space is essential to extinguish the fire effectively. Because CO2 is less efficient at cooling than water, ventilation of the engine room should not be started until it has been established both that the fire has been extinguished completely and that conditions are no longer sufficient for the fire to restart, a process that takes hours. However, the crew heard water in the engine room and re-entered the space after about 30 to 40 minutes to investigate its source. Later, they entered the auxiliary engine room, another part of the sealed space, to access the auxiliary generator. Both actions re-introduced oxygen into the space. Crew members followed documented procedures for use of the CO2 fixed fire suppression system. However, they were unaware of the need to wait for the space to cool before re-entering,” said the TSB.
A lack of understanding of the requirements for using CO2 fixed fire suppression systems has been a factor in several other occurrences in Canada and worldwide, says the TSB, citing several examples.
In the engine room fire on the bulk carrier Tecumseh, crew members re-entered the engine room in consultation with vessel and shore-based management, approximately two hours after the CO2 release and some boundary cooling and the fire reignited.
In an engine room fire on the fishing vessel Frederike, the engine room was not sealed before the CO2 was released and the fire was not suppressed.
In Canada, the use of fixed fire suppression systems is covered in Marine Emergency Duties (MED) Advanced Firefighting training, which Transport Canada requires for certain certificates of competency. Although the Atlantic Destiny was equipped with a CO2 system, the MED Advanced Firefighting training was not required for the senior deck officers. This meant that they had never been formally trained in the use of CO2 fixed fire suppression systems.
“Given several occurrences during which the effectiveness of CO2 was compromised during the fire response, the Board is concerned that there is insufficient crew knowledge of the necessary pre- and post-release stages in the use of CO2 fixed fire suppression systems,” said the report.
“If training, familiarization, drills and procedures do not cover all areas needed for an emergency response, such as the use of CO2 fixed fire suppression systems, there is a risk the crew will be unable to respond effectively to a shipboard emergency.”
Another contributing factor to the Atlantic Destiny’s sinking was the fact the crew were unable to access the sea bay valves and onboard bilge pumps were unavailable. As a result, the flooding of the engine room could not be controlled, leading to the sinking of the vessel.
“In this occurrence, overspeed protection did not automatically work. Then, when the second engineer attempted to shut down the engine by pushing the emergency stop button, it is likely that either the solenoid did not extend to trip the mechanical linkage and disconnect the fuel rack from the actuator, or the mechanical linkage was not functioning correctly,” said the TSB.
“The explosion of the shaft generators and associated machinery projected multiple hot metal fragments and hydraulic fluid throughout the engine room and started a fire. The metal fragments also damaged the seawater cooling system piping, resulting in an uncontrolled ingress of water.”
While three search and rescue (SAR) pumps were dropped to the Atlantic Destiny, they were ineffective because the hose lengths were insufficient and because the strainers became blocked repeatedly; therefore, it was not possible to keep up with the rate of water ingress.
“Pump kits provided by air SAR resources may not be effective for all sizes of vessels and operating conditions. If the conditions on a vessel in distress are outside the design parameters of a pump kit, there is a risk that the pump kit will not control water ingress at the expected rate, reducing the time available for the rescue operation,” said the TSB report.
Between 2011 and March 2021, the TSB was informed of 177 fires on board commercial fishing vessels in Canadian waters; 174 of the vessels were Canadian. In at least 57 cases, a fire in the engine room was reported. In 14 cases, the crews abandoned their vessels.
Commercial fishing safety is a TSB Watchlist issue.
“The TSB has long sought to improve commercial fishing safety. The TSB has been monitoring commercial fishing safety since 1999 and this issue has been on the TSB Watchlist since 2010. Every year, the same safety deficiencies on board fishing vessels continue to put at risk the lives of thousands of Canadian fish harvesters and the livelihoods of their families and communities,” said the TSB.
The TSB is an independent agency that investigates air, marine, pipeline and rail transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.
