An interesting analysis of flammable vapor explosions in the shipping industry. The report provides some brief details of the incidents, with causes. Everything from hotwork to static is covered. I especially like using the one where the sample was being obtained from a hold using a metal bucket and fiber rope in my flammable liquids training courses. There are many great learnings from these incident for ALL INDUSTRIES.
10/06/1996 - HOTWORK
Wasted plating was being repaired by welding in way of No.4 foam monitor when an explosion and fire occurred in the vicinity of the port and starboard slop tanks and No.7 Centre tank. The supervising Chief Officer received first degree facial burns. One repairman suffered severe third degree burns to his entire body and later died. The other repairman also received third degree burns to his body and was evacuated by helicopter to hospital. Severe damage was caused to the above-mentioned tanks and pump-room.
Probably flammable vapours in either the port or starboard slop tanks being ignited by the hot work. The dangers of hot work, particularly on tankers, are not always taken into account by ships personnel even though, as in this case, they are aware of Company and Industry regulations or recommendations. The Master issued a hot work permit but did not follow either the Companys instructions or the Liberian Bureau Marine Notice, although both he and the Chief Officer were aware of them. Company, industry and flag State requirements are not always followed.
It is recommended that the FP Sub-Committee consider the issue of an MSC circular covering hot work on ships in general to try to reduce the continual loss of life. 20% of the current fire casualties result from this cause and this is probably close to the overall figure for loss of life in fires/explosions for crew members.
05/12/1999 - HOTWORK
This asphalt carrier was out of service, without valid certificates, undergoing repair, with holes cut in the ships bottom, in a floating dry dock. In brief, she was not subject to IMOs Conventions. On 05/12/99, hot work was being carried out in No.3 port cargo tank whilst that same tank was being
cleaned. One of the shore workers was trapped inside the tank and died when a fire broke out. The fire was extinguished by the ships crew in 15 min.
There was no adequate supervision, no watcher at the tank hatch, no arrangements for rendering immediate assistance and no permit-to-work posted.
The issue of IMOs involvement: In this analysts clear view, the vessel was not subject to IMOs Conventions at the time. The importance of ensuring that national legislation for the protection of shore workers when ships are under repair. The responsibilities of all parties should be clearly defined in a written agreement before repair work is started. The shore cleaner would have had no conception of the dangers of his position but this is an ILO rather than IMO matter. Observation: The summary has been prepared from a Casualty Report commissioned by Panama. No documentation from other parties
has been sighted or requested. There is a danger of IMO being drawn into litigation if its analyses express opinions on matters outside IMOs purview. However, the FSI Sub-Committee may wish to issue general advice to seafarers, as contained in the Casualty Analysis Group Report on the second and third points of the Issues Raised.
19/07/1997 - SPLASH FILLING / STATIC
At a wharf, on 16/07/97, this oil tanker was stripping tank washings (approx. 1/3 gasoline, 2/3 water) using a portable gasoline driven pump on deck with its suction hose in the tank being stripped and its ungrounded discharge hose passing through the tween deck escape hatch and extending to approx. 1 m below the main deck level. The washings fell freely through the tween deck space into a cofferdam below, which was common with the engine-room via an engine-room escape door. Soon after the suction hose had been lowered into No.5 C tank and the Chief Engineer entered the engine room, an explosion occurred. The owner was blown overboard and killed; the Chief Mate and a deck hand were burned; the Chief Engineer was severely burned and died in hospital. The subsequent fire destroyed the wharf and the tanker was a complete total loss. Several potential ignition sources were present. In the subsequent examination, a portable DC pump was found in the ER bilge. Its discharge hose led to the open ER escape door and the cofferdam. The tankers stripping system had fallen into disrepair and disuse. For over 10 years this same unsafe system had been operated by improperly trained personnel (only the Chief Mate and Chief Engineer held tankers endorsements issued on the basis of service for this unsafe system. The crew should have complied with the 01/01/96 STCW Standards for tankers personnel. Domestic tankers present the same (or greater) hazards as deep sea tankers and the FP and STW Sub-Committees should consider issuing reminders of the need for inspections and application of the STCW Convention to such vessels. There were serious problems due to the unqualified owners reliance on the long-serving Chief Mate and by passing the
Master (no tanker endorsement). It is, however, doubtful whether the HE WG could benefit from this case.
26/03/1999 - HOTWORK
The single hull oil product tanker was in ballast with no cargo on board lying at the anchorage of a West African port. An Able Seaman and an Ordinary Seaman were employed in cleaning No.1 Centre Tank; at the same time a Deck Fitter and another Ordinary Seaman were working on the catwalk to repair the rail on the catwalk. The site of this repair was directly above the Butterworth hatch in No.1 Centre Tank and they were equipped with a grinding machine. This work was ordered by the Chief Officer. An explosion occurred in No.1 Centre Tank at 1345 hours (local time). The two men working in No.1 Tank were injured and brought to the deck by 1350 by crew who assembled to assist in dealing with the incident. The two men who had been working on the catwalk were also injured and given assistance. All of the injured seamen were given first aid and then conveyed to hospital for medical treatment. Later, the two men who had been working in the tank died from their severe burn injuries. The vessel sustained extensive structural
damage.The explosion was most probably caused by the ignition of pockets of gas in No.1 Centre Tank by sparks from grinding work on the catwalk immediately above an open tank cleaning hatch. The grinding work on the catwalk while tank cleaning was in operation was in contravention of the procedures laid down in the Safety Manual of the vessel. The risk of carrying out hot work on tankers is recognized in the procedures in the Safety Manual which require that:
- Permits are required for all hot work;
- It is recognized that the explosion resulted from a simple failure to observe established and well documented safety procedures in relation to tank cleaning and hot work. The owners of the vessel are accordingly recommended to take appropriate measures to ensure that all established safety procedures, particularly in regard to tank cleaning and hot work, are strictly observed by crews on their vessels.
- Hot work is not to be carried out while tank cleaning is in progress;
- Procedure for hot work is reviewed by those concerned before beginning.
26/12/1997 - SPLASH FILLING / STATIC
This small product tanker was loading kerosene into No.2 port cargo tank on 26 December 1997. This tank had previously been loaded with gasoline and had been gas freed during the short return journey only by natural ventilation. At about 0955, an explosion occurred in No.2 port cargo tank due to static electricity which injured four crew members. Established safety procedures were not followed. The end of the inlet pipe was not submerged
and kerosene was projected upwards through its U bend and then fell. The crew had no relevant tanker safety training. Personnel should be fully trained and certificated in oil tanker procedures. Correct operating procedures should be followed including loading rates. The operators did not appear to realize the potential dangers inherent in handling dangerous cargoes. Their interest laid elsewhere in (e.g.) purchasing a phone card, ascertaining the condition of hawsers or in the bathroom.
17/01/2001 - STATIC generated during sampling tank
Vessel had completed loading a cargo of benzene into 12 cargo tanks. Near completion of loading the vessel was boarded by a cargo surveyor (CS). The pumpman observed the CS taking samples from the aftermost tanks and working forward. Approximately 25 min after the last tank was loaded an explosion occurred and fire developed near the forward part of the cargo area. A general alarm was sounded, the foam extinguishing system activated and the fire was extinguished in several minutes by the Master and another crew member using deck monitors. The No.1 port cargo tank lid was blown off and other superficial damage was noted on nearby structures and pipework. The cargo surveyor had been injured, was provided
with first aid, and was removed by ambulance.
A static charge had developed in the cargo tank prior to the explosion and had not dissipated in the 20 min which elapsed since topping off. The CS used a metallic can attached to a man made fibre rope to obtain samples which facilitated a discharge of static electricity within the tank and resultant explosion. The CS was not knowledgeable as to the risks associated with the equipment he was using and had not followed shipboard or other established procedures. Vessel crew members did not confer with the CS as to his methods and equipment used to sample tanks. There are no assurances that shore-based service providers like cargo surveyors may understand the risks associated with their activities, nor may their operation and
safety procedures be adequate for a particular vessel or cargo. A brief inquiry by a competent vessel deck officer into the surveyors methods and equipment used during sampling may have revealed inadequacies and prompted the use of safer methods and equipment. The general workload and responsibilities of the Chief Mate while completing the loading process may have contributed to his inability to note the surveyors methods and equipment. Had he done so, the casualty could have been prevented. The CS failed to recognize risks in the methods and equipment he chose to use.
12/06/2001 - VENTILATING for CS ENTRY
During tank cleaning operations while at sea, the crew was ventilating a tank using two steam-driven fans connected to duct hoses leading to the bottom of the tank. A third fan which was driven by compressed air was in place and rigged with the ducts but was not being used. In the early morning after several hours of ventilating, flames were seen shooting out of the tank followed by a series of explosions. The fire was extinguished by the crew in
approximately 3 hours; however the vessel suffered serious damage. That evening, the crew realized the vessel was breaking in two and abandoned ship using the two lifeboats. Two crew members were inadvertently left on board. In response to the distress, two vessels picked up the crew from the lifeboats. Two crew members lost their lives while boarding the ladder during recovery operation in rough sea condition. Several ships searched the area but the four missing seamen were not found. The crew had completed washing another tank without incident and had used the inert gas system as
prescribed in procedures. During this tanking cleaning operation, the IG system was not used and it could not be determined why because the officer in
charge was missing.
The source of ignition could not be determined. The crew did not take time to prepare for potentially having to abandon ship. The lifeboats were not
lowered to the embarkation deck and to verify all was in proper running order. At the time of abandoning ship, a crew member was left on the embarkation
ladder because the lifeboat engine was inoperative and they were unable to row back alongside. In the report, there was nothing to indicate the safety procedures or fitted equipment was inadequate or that the officer in charge was not aware of or did not normally follow them. However, the circumstances leading up to the explosion showed that they were not properly applied or used in this instance indicating that some procedural checks assigned to different crew members could be employed to ensure certain key steps in safety procedures are followed. The need to use lifeboats is never planned and
this accident confirms the requirement to continually verify that they are in proper working order. In any operation, the crew must continually assess the risk of an accident. As in the case of the explosion, procedural checks would reduce the probability of the development of a hazardous situation. With respect to the lifeboat, projecting potential consequences of a hazardous situation would have concluded with the need to potentially abandon the ship and to be prepared, especially given the fact that such preparations would not negatively have impacted upon the safe operation of the ship.
15/01/2001 - STATIC from CLOTHING the ENTRANTS wore
After discharging gasoline in one port, the tanker was making an 11-hour transit to the next port where the next cargo was to be loaded. Following the instructions of the charter, the crew started tank cleaning operations by fitting a water-driven fan to ventilate the tank with ducting extending to
the lower portion of the tank. Due to the freezing weather, the water in the pipes was freezing making the operation of the fans difficult and necessitated starting the operation from the after tanks. After completing the ventilation of the tank just forward of the slop tanks and considering it to be gas free, two crew members entered the tank to remove residual oil. There was an explosion which tore away bulkheads to adjoining tanks. One such tank contained A-1 Jet Fuel and Kerosene slops which ignited. The hull was breached in way of the tanks and the engine room and the ship flooded rapidly, developed a starboard list and sank. The crew escaped by jumping into the sea and seven were recovered by passing ships. Of a crew of 16, 7 survived, 3 bodies were recovered and 6 were missing. The source of ignition was not identified; however, it was indicated that it was highly probable either due to a discharge of static electricity from winter clothing or from the ventilation ducting; or to an ordinary metal paint can that was used to carry tools into the tanks coming in contact with metal and causing a spark. Whereas it is normal procedure not to enter tanks until gas concentration are below danger levels, it could not be determined if the officer in charge of the operation followed these procedures properly. The crew was under pressure to complete the tank cleaning operation due to the short duration of the transit to the next port in that given the equipment available and the weather conditions, there was insufficient time to ventilate and clean all the tanks as was requested. Given the type of cargo to be loaded in the next port, the report disputes the need to clean tanks in this case. The investigation report indicates the need for stricter standards including the fitting of inert gas systems; cleaning tanks only when necessary; using fitted piping for loading and discharging as a means to blow air into tanks; and situating slop tanks close to the bow. There is a need to ensure having sufficient time to conduct tank cleaning operations to minimize the possibility of missing steps in or not paying adequate attention to the operation. All the crew had taken training in tanker operations; however, there is a need to continually reinforce this training on board and to ensure the lessons are properly applied.
02/06/2001 - USING NON-INSTRINSICALLY SAFE PUMP
The vessel was alongside undergoing repairs following a period of time that it had been laid up. During the process of replacing an expansion joint in one of the tanks, it was realized there was a quantity of Premium Motor Spirit in the tank. An electrical submersible pump was to be used to pump the oily water mixture. The pump was lowered in the tanks and soon after it was started, an explosion occurred severely rupturing the cargo tanks. As a result of the explosion, 6 shore workers and one of the ships officers died. As well, one shore worker and another of the ships officers were admitted to hospital. There was an explosive meter on board and tanks had been tested some time before; however, there is nothing to indicate that the atmosphere in the tank had been tested on the day of the explosion. The ships eduction pump was not used and the electrical submersible pump that was used was faulty or not intrinsically safe to be used in such conditions. The Masters experience was, for the most part, on general cargo and container vessels and not on tankers. When working with oily water mixtures in tanks, ships crew members should not assume that the tank is gas free and should only use equipment designed for such purposes.
13/06/2003 - STATIC from PRESSURE WASHING (WATER)
On 12 June 2003, the tanker Chassiron called at Bayonne, France, to discharge its cargo of petroleum products. At 0500 on 13 June, the tanker departed Bayonne for Donges, France, to load other cargo. Two crew members began to clean the cargo holds. A few minutes after the cleaning had begun on no.6 port and no.6 starboard holds, in which 98 unleaded gasoline had previously been loaded, a loud whistling noise was heard just before three instantaneous explosions and a fire. An initial explosion occurred in no.6 starboard cargo hold, followed by an explosion in no.6 port and then in no.5 port. The crew member who was in the vicinity of the no.6 cargo holds was killed. The other crew member at the loading/unloading manifold, located midship and forward of the no.6 cargo holds, was unharmed. No.5 port and no.5 starboard cargo holds were also damaged as a result of the explosion. The deck between the superstructure and the manifold was completely destroyed. The fire was brought under control within an hour.
The tanker was permitted to return to Bayonne for repairs. The levels of hydrocarbons and oxygen within no.6 port and starboard cargo holds were within the explosive limits. While it is possible that the source of ignition may have been of a mechanical origin (such as a malfunction of a cargo pump causing an increase in temperature), it is likely that it was the result of an electrostatic origin caused by the cargo pump or washing nozzle.
- Reducing the risk of the formation of explosive gas in the petroleum cargo holds.
- Reducing the possibility of ignition sources.
- Requiring the fitting of inert gas systems for tankers of less than 20,000 tonnes carrying petroleum products having a flash point not exceeding 60ºC.
There do not appear to be any significant human factor-related issues that have directly contributed to the accident.
28/02/2004 - UNKNOWN SOURCE, Sources that could not be ruled out include electrostatic discharge; mechanical sparks caused by metal-to-metal contact; faulty electrical equipment; hot soot or particles from the funnel; sparks from changing the batteries of portable electrical equipment in a
At 1805hrs on 28 February 2004, the chemical tanker Bow Mariner caught fire and exploded while the crew was engaged in cleaning residual MTBE from cargo tank No.8 Stbd. The ship sank by the bow at 1937 about 45 nautical miles east of Virginia, United States. Of the 27 crew members aboard, six abandoned ship and were able to make it to an inflatable raft and were rescued by USCG. An unknown number of other crew members abandoned ship to the water. USCG and other vessels recovered three of these crewmen from the water, one deceased. The other two died before reaching hospital. 18 crew remain missing and are presumed dead. The cause of this casualty was the ignition of a fuel/air mixture, either on deck or in the cargo tanks. The ignition source could not be precisely determined.
1. The cause was the ignition of a fuel/air mixture that was within its flammable limits, leading to a fire on deck.
2. The ignition source could not be determined. Sources that could not be ruled out include electrostatic discharge; mechanical sparks caused by metal-to-metal contact; faulty electrical equipment; hot soot or particles from the funnel; sparks from changing the batteries of portable electrical equipment in a
3. Opening the 22 cargo tanks that previously held MTBE permitted flammable vapours that were heavier than air to accumulate on deck and diluted the fuel-rich atmosphere in the cargo tanks with oxygen, bringing them into the flammable range.
4. The fire was followed by two significant explosions that occurred less than two minutes apart. Each of these explosions was actually a series
of rapid explosions as each of the empty tanks exploded within seconds of one another.
5. The explosions caused catastrophic damage leading to immediate flooding of nearly the entire cargo block. The ship sank within 1 h 32 min of the first explosion.
6. Contributing to this casualty was the failure of the operator and the senior officers to properly implement the company and vessel Safety, Quality and Environmental Management System (SQEMS).
7. The cargo tanks were not inerted during the previous discharge of MTBE, as required by the SQEMS. The tanks were not required to be inerted by U.S. law or International conventions because the vessel was constructed before 1 July 1986. If the tanks had remained closed the explosions would not have occurred.
8. Opening the tanks exposed the crew to toxic fumes, permitted flammable vapours that were heavier than air to accumulate on deck and diluted the
rich atmosphere in the cargo tanks, bringing them into the flammable range.
9. The entry of the boatswain into the cargo tanks wearing an SCBA was dangerous and ill-advised, but did not violate the Managers Confined Space Entry Policy in effect on the date of the casualty. That policy has since been revised to prohibit entry under the same circumstances.
10. The failure of the Master to properly organize a response to the explosions contributed to the high loss of life. He abandoned ship without sending a distress signal, without attempting to contact a nearby ship, without conducting a proper muster or search for injured crewmen, and without attempting to launch primary life-saving appliances.
11. The Master and Chief Engineer abandoned ship within 10 min of the first explosion, leaving behind crew members they knew to be alive. Their premature action exposed the crewmen who entered the water with them to the cold water far earlier than necessary, and contributed to the high loss of life.
12. The actions of the Third Officer, making his first trip as a licensed officer, were commendable and helped save the lives of himself and five others.
13. The lack of immersion suits contributed to the high loss of life.
14. The failure of the Master to conduct regular and effective fire and boat drills contributed to the high loss of life.
15. There is evidence that the Operators and senior officers failed to follow proper relief and indoctrination/ familiarization training for critical crew members.
16. There is evidence of lack of cohesiveness between the three senior officers, who shared the same nationality and the other officers and crew, who shared a different nationality, but it could not be determined if this contributed to the casualty.
1. That vessels Operators review their internal policies and procedures concerning workforce interaction and cooperation, including but not limited to delegation of appropriate duties to qualified officers.
2. That legislation on Inert Gas Systems be revised to require the inerting of all cargo tanks carrying flammable cargoes aboard vessels equipped with Inert Gas Systems, regardless of the vessels date of build (NOTE − this recommendation of the Investigating Officer was not supported at a higher level due to the complexities of the carriage of chemicals, some of which might be contaminated by the inert gas. It is included in this analysis to offer the
opportunity for further discussion if deemed appropriate.)
3. That IMO, ICS and INTERTANKO be approached to form a study group to examine the causes of all tank vessel explosions in the last five years involving tank cleaning to search for common factors.
4. To make the report available to the maritime industry in an effort to promote safe practices aboard ships.
S1. That the vessels Operators develop ship specific oil and chemical Cargo and Ballast Operations Manuals with separate procedures for oil and chemical tanker operations.
S2. That the vessels Operators review the statement emphasizing the Masters authority, to align it with the ISM objectives.
S3. That the Operators have a special audit of the SQEMS by the classification society. To make the audit more focused, the classification society should be given in advance the deficiencies found during the investigation of the Bow Mariner incident.
S4. That the Operators take measures to improve the shipboard social culture to ensure social cohesiveness.
S5. That the Operators debrief the signed off crew to obtain feedback on shipboard safety culture, social cohesiveness, and operations.
S6. That the Operators emphasize the importance of crew cohesiveness to senior officers in the fleet through proper training programmes, e.g., team building.
S7. That the Operators develop procedures for entry into contaminated tanks as required in section 3.5 of the Tanker Safety Guide Chemicals.
S8. That the Operators monitor work/rest periods of Chief Officers so as to ensure they are not affected by fatigue and remain fit for duty.
S9. That the Operators ensure crew familiarization and compliance with overlap time requirements during crew changes in accordance with the ISM procedures.
It was determined during the inquiry that several requirements of the Companys SQEMS were not followed. While several of these omissions may not have contributed directly to the casualty they are nevertheless safety related.
1. The cargo tanks were not inerted as required by the Cargo & Ballast Operations Manual (CBOM).
2. The procedures for tank cleaning given in CBOM and Dr Verweys Tank Cleaning Guide (incorporated by reference in the SQEMS) were not followed.
3. Procedures for confined space entry of the Fleet Operating Procedures Manual (FOPM) and the CBOM were not followed.
4. Failure of one of two IGS blowers were not reported as a non-conformance as required by the SQEMS.
5. Monthly fire drills were not conducted as required by SOLAS regulation 19 and of the FOPM.
6. Training was scheduled and recorded in the Minutes of Safety Committee Meetings but, according to survivors was not always conducted.
7. Overlap voyages of key personnel were required by the FOPM but in the case of the second assistant engineer making his first voyage on the vessel he and the departing engineer crossed on the gangway.
8. None of the survivors went through indoctrination or familiarization as described in the SQEMS.
9. Officers below the grade of chief officer and chief engineer had not read applicable portions of the SQEMS.
30/04/2005 - PUMP SHAFT RUBBING AGAINST CASING
On 30 April 2005, at 0110 local time, the chemical tanker Metanol docked at the oil terminal at Lavera, France, to discharge a cargo of methanol. About 15 to 20 minutes into the unloading of the cargo, an explosion occurred in way of cargo tank no.12. The fire was extinguished by the crew. There were no injuries. There was minor damage to the vessel.
The accumulation of combustible vapours in the cargo tank. The intermediate shaft of the cargo pump was rubbing against the casing, providing a source of ignition. There was no inerting gas system fitted on the vessel. An inerting gas system was available in port; however, its use was not imposed by the port authority. The port procedures did not address the usage of the shore-based inerting gas system. The importance of carrying out suitable maintenance of shipboard machinery and equipment. The use of an inerting gas system on board tankers of less than 20,000 tonnes, including chemical carriers. The importance of having a well trained and equipped crew to effectively respond to
01/01/2004 - DAMAGED BONDING CABLE
A series of explosions took place inside the cargo tanks and a subsequent fire broke out on board the vessel when unloading chemical Cut C6 − benzene type product in the port of Porto Torres in Sardinia, Italy on 1 January 2004. Two seamen on the main cargo deck were killed and the Chief Officer was injured. The fire was eventually brought under control by the local fire brigade. The damage caused resulted in the vessel being declared a constructive total loss.
a) The bonding cable was partly corroded internally and not well maintained; this corrosion would have affected its electrical continuity even if it had been connected between the terminal and the vessel correctly; and
b) crew members did not check and confirm with the terminal whether the bonding cable was required or not.
The terminal personnel believed the bonding cable should have been used, but were unsure who (if anyone) connected the cable.
a) General confusion surrounding the use of bonding cables, particularly when the national or local regulations are not in line with the current industry guidelines;
b) while there is a clear terminal responsibility, with respect to the application of national and local requirements, the Master, Officers and Crew have a duty to ensure the safety of the vessel and those on board; and
c) the installation of inert gas systems on board chemical tankers, irrespective of ships size, can enhance fire or explosion safety.
04/06/2004 - STATIC from LIQUID INTERFACE
At 1435 hrs on 4 June 2004, the 37272 dwt chemical tanker NCC Mekka was in the process of tank cleaning when a low pressure explosion occurred in tank 1CS which had previously carried parrafinic solvent. This was followed by another explosion in the adjacent tank 1CP which was fully loaded with ethanol. The deck was fractured in several places and the escaping ethanol caught fire, the fire spreading all the way aft to the deck house. The vessel was en route from Santos to Aratu (Brazil). The crew extinguished the fire by 1505 hrs, using the vessels foam monitors, and managed to bring the vessel to the Rio de Janeiro roadstead. One able seaman and the Boatswain were badly burned and subsequently died. Water ballast tank no.1 starboard was fully charged, while water ballast tank no.1 port was empty. Water-driven rotary tank-washing machines were being used to wash tanks which had contained parrafinic solvent which from a product data sheet subsequently provided by the shipper was found to have a flash point of -40°C.
Prior to the explosion the tanks had been subjected to a half-hour cold seawater wash, followed by a two-hour hot seawater wash at about 60°C. About 200 litres of detergent had then been added to the tank via the closed sampling inlet of a Butterworth hatch. 2 to 3 c.metres of fresh water was added via the cargo line system and a three hour washing programme commenced, using the fresh water/detergent at ambient temperature. This fresh water/detergent wash was in progress at the time of the explosion.
Investigators considered various sources of ignition, including mechanical friction from the cleaning machines and/or the deepwell pump, electrical short circuit in tank monitoring systems and structural damages. All these were excluded based on information available and A data sheet (commodity information) that the NMI found available on board at the maritime inquiry did not specify whether paraffinic solvent (which is included in the category naphtha in MARPOL Annex I) was flammable, nor did it specify the flash point of the substance. There was no mention of whether such information had been requested. (The data sheet gave the product name as paraffinic solvent, shipping name: naphtha solvent). The NMI received another data sheet at the company office on 25 June. In this sheet it was stated that the flash point was -40°C, and that the substance was flammable. There is a discrepancy between the requirements of MARPOL Annex I oil products and Annex II chemicals with regard to the carriage of paraffinic products. No unambiguous safety management and quality assurance system procedures and instructions could be put forward, requiring the use of inert gas upon loading, carriage, unloading and cleaning of MARPOL Annex I products with a flash point below 60°C.
Due to the explosion, cracks were formed between these tanks, and water ballast therefore ran over to the port tank. This contributed to a list of the ship to port of about 5 degrees. Cracks also formed between tanks 1CS and 1CP and between those two tanks and the water ballast tanks. This caused ethanol from 1CP to run down into the water ballast tanks and over into 1CS. There were bulges, but no punctures or cracks in the outer bottom and hull. Following emergency consultations with the company, the master decided to perform an emergency discharge (ethanol and water ballast) into the sea.
examinations carried out after the explosion. The conclusion was that there must have been a charged atmosphere in tank 1CS, and that a static discharge had taken place inside the tank. What led to the discharge was not clear but it was postulated that a static charge could have been created from the detergent-loaded water wash. The presence of human error could not be excluded, but nothing in particular was specified that could indicate such error.
Although the vessel was fitted with an oil burning inert gas generator the cargo tanks were not inerted at the time of the casualty. At the maritime inquiry, the chief mate stated that the inert gas system on board (which was based on oil combustion) was unacceptable to the charterers because of too low purity. However no explanation was given as to why nitrogen was not used for inerting or why, in the absence of an inerting medium the cargo was not rejected. Procedures were on board, but they were not clear on this point. In violation of the companys procedures, the deceased able seaman did not attend the so-called pre-cleaning conference prior to the commencement of tank cleaning. The rest periods of the Chief Officer, Boatswain and able seaman involved in the incident were, in the three days prior to the pre-planning conference and subsequent cleaning operation, below the STCW Convention requirement for at least 10 hours in any 24-hour period (however, there was nothing that clearly indicated this was a causal factor to the casualty). During the fire-extinguishing operation it appeared that the foam pump did not work in a fully satisfactory manner. One of the components had overheated. It was later concluded that the system was constructed for 110 V and not 220 V as provided in the ship.
1. It is important that the Master is provided with data sheets which include all necessary and correct - information for the safe handling, storage and treatment of the cargo to be carried.
2. When Masters are presented with cargoes which require specific conditions of carriage which are not available e.g., inerting with gas of a specified purity such cargoes should be refused.
3. Although not considered by the investigators as directly contributing to the cause of this incident, rest periods required by the STCW code must be met
4. The cleaning of tanks was not treated by the ships safety management and quality assurance system as a critical work operation before this casualty occurred, nor were there any unambiguous instructions provided requiring the use of inert gas with MARPOL Annex I products with a flash point below 60°C.
15/12/2004 - STATIC from STEAM NOZZLE used during CLEANING
On 14 December 2004, the vessel discharged a cargo of Reformate. This cargo, which is a dangerous and flammable liquid, is used as a base material in the production of gasoline. Whilst on a ballast voyage, the vessel sustained an explosion in her cargo length area on 15 December 2004. The flame, which started in one of her cargo tanks during tank cleaning operations, spread to adjoining tanks, igniting flammable gases inside. This resulted in almost all the deck plating being blown off and the side shell plating holed resulting in tank flooding. Both the bosun and two other sailors, who were on deck at the time of the explosion, went missing. Eventually, the fire was brought under control but the vessel sustained a serious list and subsequently foundered. Pollution was also recorded as a result of fuel oil spillage from her tanks.
1. Although not definite, it is presumed that the steam nozzle used in the tank cleaning may have created a static electrical discharge in an explosive
2. Gas-freeing period lasted only 1.5 hours resulting in a lack of air changes inside the cargo tanks;
3. Subsequent gas testing was only planned to be conducted through the oil-tight hatch in the aft part of each tank rather than in other locations such as in the middle or forward sections of the tank;
4. Whilst the response time for the gas detector (with a pipe length of 20 m) was approximately 34 seconds, the chief officer assumed that the response time was instead 15 seconds (which corresponds to a 1 m sampling pipe);
5. The vessel was not fitted with an inert gas system.
One needs to highlight the importance of adequate use of gas measuring equipment instruments, which are capable to measure gas in various tank atmosphere conditions. Another important factor relates to the dangers of steam cleaning due to static electrical discharges. Established guidelines
in the industry caution about the dangers of:
- mist cloud generation inside the cargo tank, which may be electrostatically charged;
- levels of charging, which may be much higher when steam is introduced (in comparison with water washing);
- less time periods to reach maximum charge levels in comparison with water washing; and
- capability of steam disturbance to release gases resulting in flammable pockets build-up.
The report reflects multiple failures in the decision-making process of both the master and the chief officer. So much so that it concludes that their final decision as to the planning and application of the cargo washing operation contributed to the explosion of the cargo length area. Nevertheless, the concept of human element and organizational safety is not investigated in detail and does not leave much room for analysis with respect to the decision-making pattern of the above-mentioned two officers. The report indicates that both the master and the chief officer were fully competent, mentally sane and physically fit to man this type of ship. There is no indication as to why (what seemed to be) a normal day of work resulted in a tragedy and subsequent loss of the ship. In other words, the report describes very clearly and in an elegant manner what went wrong and what should have been done in order to avoid the explosion. However, it does not explain why two competent officers at the management level decided in such a way that (with the benefit of hindsight) their joint decisions contributed to the vessel sustaining an explosion.