CONTENTS 1 1.1
Introduction The risks are real
2 2.1
The IMSBC Code What the Code contains
3 3.1 3.2 3.3 3.4 3.5 3.6 3.7
The Bulk Cargo Chain Ship suitability Cargo documentation Port storage Inspection, survey, sampling and testing Loading The passage Discharge
4
Personal safety
5
Being methodical
6
Further resources
1
INTRODUCTION
This Reference covers the principles that govern the handling and carriage of all bulk cargoes. Together with the DVD, it is suitable for both initial and refresher training. While it puts forward a methodical approach to dealing with dangerous and difficult bulk cargoes, you should be aware that it does not cover every aspect to be considered about specific cargoes. The mandatory International Maritime Solid Bulk Cargoes Code (IMSBC Code) produced by the International Maritime Organization is the key resource for all the information that needs to be taken into account for any particular cargo. 1.1 The risks are real Unfortunately, there is no shortage of examples to make the point that bulk cargoes need to be treated with the utmost respect. ·
A bulk carrier carrying direct reduced iron (DRI) fines from Venezuela to China was lost as the result of a rapid series of explosions after the hydrogen gas that had built up in the holds ignited. Six members of the crew were killed.
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After three days at sea, a bulk carrier taking nickel ore from New Caledonia to Australia developed a 15° list after the cargo in four of the five holds liquefied. Ballast had to be pumped urgently to correct the list and enable the ship to make port.
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A ship carrying zinc skimmings from France to Italy foundered and sank within a minute after a severe explosion following the build up of gas in the hold. Six out of seven crew members lost their lives, and the sunken ship was never even located.
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A ship carrying a cargo of iron ore fines only managed to sail a few miles from its port of loading before developing a list which became so severe that the ship was beached to prevent capsizing. The cargo had liquefied.
There can be no question of these incidents being caused by bad luck. They were caused by bad practice.
2
THE IMSBC CODE
In order to codify best practice, the International Maritime Organization has published the International Maritime Solid Bulk Cargoes Code – usually known as the IMSBC Code. This is officially in force from 1 January 2011, from which date it will be mandatory under the provisions of the SOLAS Convention. The IMSBC Code supersedes the Code of Safe Working Practice for Bulk Cargoes (BC Code) and presents additional information including the Code of Safe Working Practice for the Loading and Unloading of Bulk Carriers (BLU Code) and recommendations on the safe use of pesticides in ships applicable to the fumigation of cargo holds. Being a mandatory document, it has to be aboard every bulk carrier, and its requirements followed. But this is not just a case of yet another set of rules. The
IMSBC Code is there to help prevent accidents and incidents by informing seafarers about the risks associated with bulk cargoes. These risks fall into three main categories: ·
Risk of structural damage This can occur through incorrect cargo distribution but can also be caused by corrosion. Equipment can also be damaged, especially by dust during loading and unloading.
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Risk of instability during the voyage This is mainly a result of a solid cargo turning liquid in the hold.
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Risk of chemical reactions within the cargoes Principally those which generate heat, explosive gas or toxic gases.
The IMSBC Code provides information on the characteristics of the cargoes and instructions on the procedures to be followed when solid bulk cargoes are due to be carried. It is essentially a reference book to help ships’ officers assess whether a particular cargo is acceptable. 2.1 What the code contains The IMSBC Code has several general sections at the front which apply to all bulk cargoes. These include one specifically on the subject of the “Assessment of Acceptability of Consignments for Safe Shipment”, which contains details of the information about a bulk cargo that has to be provided by the shipper. It also lists the detailed characteristics of over 150 different bulk cargoes, and the handling procedures to be followed. The most fundamental characteristic is the Group to which the cargo belongs. All cargoes are classified using three categories: Group A – cargoes which may liquefy in the hold while the ship is on passage if the moisture content is higher than permitted for carriage Group B – cargoes with chemical properties that could lead to a dangerous situation onboard, such as the production of an explosive or toxic gas Group C – cargoes which are not liable to liquefy or to be a source of chemical hazards
Another characteristic that is listed, which applies to free flowing materials as varied as grain, potash and urea, is the Angle of Repose. This is the maximum permitted slope angle of the cargo when it is in the hold, measured as the angle between the horizontal and the slope up the cone.
The entry in the IMSBC Code for each cargo then lists information, warnings, and procedures to be followed, under the following headings: Hazard
Loading
Discharge
Stowage and segregation
Precautions
Cleanup
Hold cleanliness
Ventilation
Emergency Procedures
Weather Precautions
Carriage
In relation to instructions, the text makes the following distinctions between three key words: “Shall” “Should” “May”
3
= mandatory e.g. a certificate shall be provided = recommended e.g. this should be calculated = optional e.g. this check may be made more frequently
THE BULK CARGO CHAIN
It is important that the whole process of dealing with all bulk cargoes is carried out in a methodical way. In every case, the stages to be gone through in transporting a cargo from its source to its destination are like the links in a chain.
Like any chain, the strength of this one is dependent on the strength of each of the individual links. The difficulty for seafarers is that some of the critical links are in someone else’s control. But as the examples earlier in this guide show (and there are many others), it is the ship and the crew that are at risk if a link in the chain proves faulty. So the Master has to be satisfied that every link is sound – even when someone else is theoretically responsible for it. 3.1 Ship suitability Every ship has a Certificate of Compliance with Group A, B or C cargoes, or a Certificate of Fitness for carrying solid bulk cargoes. Therefore, the suitability of the ship for a particular cargo should already have been checked when the vessel was fixed on charter, or the cargo booked. But this cannot be taken for granted. There is always the possibility of errors or omissions. The IMSBC Code lays down all the requirements that apply to the ship in relation to each specific cargo, and are essential for its loading and carriage. Depending on the cargo, these could include: § The boundaries of the holds are resistant to fire and liquid § Electrical equipment in the holds is safe for use in an explosive atmosphere or can be isolated outside the holds § The ship is carrying the appropriate equipment for gas measurement § The specified type of ventilation is fitted § The necessary specialist safety equipment and personal protective equipment is on board Nothing is lost by checking – especially if the cargo booked has not been carried before. Correct identification A good number of cargoes have variants of the same basic material, and in some of these cases each variant needs to be handled differently because it presents a different hazard. It is essential to know exactly what cargo is involved. However, this might not always be straightforward, because identical cargoes sometimes go under different names, depending where in the world they are loaded. In the most extreme case, ten or more names are in use for variants of the same material. That is why the IMSBC Code specifies that the Bulk Cargo Shipping Name (BCSN) must be used. The BCSN is the name under which the cargo is listed in its detailed section of the IMSBC Code. Other names can be used, but only in addition to the BCSN. If the cargo name is not immediately recognisable or familiar, Appendix 4 of the IMSBC Code allows for cross referencing a number of commodities and materials to provide the correct BSCN as applicable to the schedules.
3.2 Cargo documentation This second link in the chain is particularly important. That is because some decisions that need to be taken by the ship in respect to cargoes – even to the extent of rejecting them as unsuitable – depend on accurate information. It is the responsibility of the shipper to provide all the information listed in the IMSBC Code. Some of it simply confirms the characteristics of a particular cargo as laid out in the Code, which do not change. But there are three areas which do change, even between two different cargoes of the same material, and where great care needs to be taken. Moisture content Excessive moisture is a major factor both in cargoes that can liquefy and in those that can be subject to chemical reactions. The shipper must therefore provide a certificate that states the average moisture content. In the case of a Group A cargo, there must also be a statement of TML (Transportable Moisture Limit) which is the maximum moisture content considered safe for carriage. Temperature For some cargoes, an increase in temperature triggers a potentially dangerous chemical reaction. The IMSBC Code specifies a maximum loading temperature for such cargoes. There will be occasions when this information will be provided but there may be doubt of how up to date it is – precisely because it is variables that have been measured. Therefore, the ship may still need to check for accuracy. 3.3 Port storage The next link in the chain, port storage, is also relevant because of the variables of Ship Stability and Cargo Documentation for which accurate information is needed. Even assuming that the figures for moisture content and temperature in the shipper’s documentation were accurate when they were measured, how and particularly where the cargo was stored in the intervening period could have had a considerable impact on the figures. This is especially true of moisture content for any cargo stored in the open when there has been recent rainfall, or the cargo is being loaded in a part of the world that has a marked rainy season. This problem would be increased if the storage area is not well drained. For some cargoes, the IMSBC Code lays down particularly stringent requirements about storage prior to loading, such as being under cover but exposed to dry weather in the open for at least three days of ‘weathering’. This is another requirement for which a certificate should be provided by the shipper to the Master. 3.4 Inspection, survey, sampling and testing As per the IMSBC Code, the certificates that have to be produced for the ship giving accurate information about the cargo record tests have to be done by competent personnel. These tests have to be conducted in accordance with nationally or internationally accepted standard procedures.
The IMSBC Code also rules that the sampling and testing for the moisture content should be done “as near as practicable to the time of loading,” and never more than seven days beforehand. However, as indicated in the previous links of the chain, there may still be reasons for the ship to question the accuracy of the figures. The IMSBC Code itself says that checks are to be conducted if there is significant rain or snow between testing and loading. The first stage is physical inspection of the cargo. This will indicate general aspects, such as whether there is obvious variability in its makeup across a stockpile, as well as giving an idea of the nature of the storage (especially whether open air or under cover), and an indication of how good the drainage might be. For cargoes where the size of the individual constituent parts is one of the defining characteristics, surveying and measuring will provide a higher level of certainty. The IMSBC Code gives the details of both what the size should be, and in what form the cargo should be – be it granules, crystals, briquettes, pellets, powder, fines, or even lumps. If it is thought necessary to take new readings for temperature or moisture content, specialist assistance may be required to take samples. It is important to take representative samples when intending to establish moisture content, both across the stockpile and at least 50cm into it, and the test must always be conducted at a laboratory. There is a similar need to probe sufficiently deeply into a stockpile when measuring temperature to get a truly representative figure. While it is always possible to call for further laboratory testing where there is any doubt, there are some circumstances where an interim test can be conducted without specialist knowledge. The ‘Can Test’, for example, described in the IMSBC Code, provides a reliable indication of a cargo with moisture content high enough to cause it to liquefy. 3.5 Loading Preparation for loading Once a cargo has been accepted for carriage, the IMSBC Code contains a considerable amount of information in each individual cargo entry to guide ships on what needs to be done before loading begins. This can be found not just in the Loading section of the entry, but also under the headings of Stowage and Segregation, Hold Cleanliness and Precautions. Actions to be taken could include: · Ensuring there is no residue of a previous cargo in the hold (which may prompt a chemical reaction in a cargo) · Making sure that the hold is dry (where chemical reaction is triggered by water) · Using only holds that are not immediately next to sources of heat (for cargoes that selfheat or give off gases if their temperature is raised)
· · · · ·
Testing the integrity of weather deck enclosures to the cargo space (for cargoes where the enclosures have to be closed and sealed) Treating the surfaces of the hold (when the cargo can cause corrosion) Isolating possible sources of ignition, like electrical equipment (for combustible cargoes or those that give off gases if ignited) Covering sensitive electronics and machinery (for cargoes that generate dust) Ensuring members of the ship’s crew involved in loading have the appropriate protective equipment (also for cargoes that generate dust)
Loading There are two different facets to the loading itself, the physical and the organisational. The physical aspects relate to the actions that need to be taken to avoid overstressing any part of the ship’s hull and to aid stability while on passage. Some bulk cargoes are of high density and weight distribution becomes even more significant. Whenever possible, the higher the density of the cargo, the lower the hold in which it is stowed. If this cannot be done, extra attention needs to be paid to considerations of overstressing and stability. Correct trimming is vital for all bulk cargoes. The relevant cargo entry in the IMSBC Code will list any additional factors that need to be borne in mind in this regard, usually under the heading of Loading, but sometimes in a special appendix to the entry for a specific cargo. The ship’s stability information booklet provides the necessary data to help ensure that the ship is loaded in such as way as to make sure its stability is at or above the minimum acceptable level. The physical aspects of loading also cover good practice such as the maximum drop height when loading is done with cranes using grabs, rather than conveyors, and the speed of loading. With this facet of loading, the IMSBC Code works in conjunction with the Bulk Loading and Unloading Code (the BLU Code). This is included as a supplement in the IMSBC Code. The organisational aspects of loading relate to the extra safeguards that the ship might need to put in place during loading. These could include: · Stopping all hot work (such as burning, cutting or welding) in the vicinity of cargo spaces · Enforcing a ban on smoking in and near the cargo spaces · Posting appropriate warning notices · Spotchecking the cargo temperature The timing of the loading can also be weatherdependent. There are a good number of cargoes that should not be loaded in rain or snow.
There are also some bulk cargoes that carry a potential security risk. Section 11 of the IMSBC Code contains provisions relating to security. When cargoes that fall in this category are carried, the ISPS Code and SOLAS regulations and guidance must be followed closely. 3.6 The passage For the many cargoes prone to dangerous chemical reactions, all the previous links in the Bulk Cargo Chain are aimed at reducing the possible occurrence of those reactions during passage. For cargoes which can liquefy, they are intended to keep the moisture content below the TML. However, there is a continuing requirement for vigilance during the voyage. As before, the IMSBC Code lays down what needs to be done. One important area is ventilation, which gets its own heading in every individual bulk cargo entry. Having the right ventilation fitted for the cargo is part of the first link in the chain. This tenth link is concerned with the correct operation. Depending on the cargo, there could be a requirement to: · not ventilate at all · make the hold gastight · open the ventilator flaps to allow surface ventilation · make use of mechanical ventilation, or · in a few specific circumstances, carry a cargo under inert conditions The requirement for ventilation can be continuous or at specified intervals. The only overriding consideration would be when maintaining ventilation would endanger the ship or the cargo (unless interrupting it would produce a risk of explosion). For many cargoes, there will also be a requirement to measure the gases they produce, both in the hold and in other spaces in the ship. (The requirement to have such equipment on board is another element of the first link in the chain, ship suitability.) The most important gases that might need to be measured, depending on the cargo, are: · methane (flammable, and potentially explosive when mixed with air) · hydrogen (this is also potentially explosive, and can selfignite) · oxygen (some cargoes will absorb this, leading to oxygen depletion in the hold) · carbon monoxide (toxic, but could also be an indicator for selfheating) With some cargoes, there will also be a requirement to monitor temperature at specified intervals. 3.7 Discharge This last link in the chain often simply mirrors the requirements laid down in the IMSBC Code for loading, except that there are likely to be fewer requirements when discharging. Typical of these is the generation of dust, and therefore the protection of
equipment vulnerable to dust damage, and the need for personal protective equipment. However, there are cargoes which have special requirements only during discharging, that arise because of the period the cargo has been in the hold. These could be as varied as: · not bunkering or pumping fuel oil · testing the atmosphere of the cargo space before any personnel enter it · continuing to test it at specified intervals while people work in the cargo space · trimming a cargo that has hardened during passage, to avoid overhangs · monitoring a potentially selfheating cargo for hot spots As in all other cases, the requirements are specified in the detailed entry for each cargo in the IMSBC Code.
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PERSONAL SAFETY
The safety of the ship is the primary purpose of ensuring that every link in the Bulk Cargo Chain is sound. That naturally includes the safety of those on board: the two go hand in hand. But there is a safety dimension that affects only people, and needs to be considered separately – because it is a regular source on its own of incidents and, sometimes, fatalities. The result of chemical reactions in many Group B cargoes is that they give off gases. Some are toxic. Carbon monoxide, a product of combustion, has already been mentioned. Others include phosphine and arsine, both of which are colourless. A comparable problem – in that there is nothing by way of visible warning – is too little oxygen to support human life. With some cargoes, oxidisation draws oxygen from the atmosphere; in a closed cargo space that leads to severe oxygen depletion. The types of cargo involved vary widely: from grain to timber, from guano to scrap metal. Furthermore, the replacement of oxygen from the air when the space is opened is not instantaneous. It takes time for the space to be fully ventilated. Even then, pockets of low oxygen atmosphere can remain. Closed holds remaining empty for long periods can also have low oxygen levels. As a result, every enclosed space should be treated with caution. This includes not just holds, but any compartment with limited openings for entry and exit, and/or little natural ventilation, and one not designed to be occupied on a permanent basis. Every ship must have procedures for entering these enclosed spaces, which will include: · ventilating the space before entry · testing the atmosphere before entry
· · · ·
not entering the space alone, and having one person outside it who is in communication with anyone inside wearing proper equipment and clothing having a system of formal permits approving entry having warning signs or posters next to the entry to an enclosed space
Procedures must be followed by everyone – without exception, and to the letter. As with all the issues that are addressed by the Bulk Cargo Chain, accidents involving personal safety are almost always not the result of bad luck, but of bad practice.
5
BEING METHODICAL
Good practice, in contrast, is taking decisions and actions on the basis of a methodical approach, i.e. following correct procedures, at all times. The Bulk Cargo Chain provides such an approach – making sure the right questions are asked and the right information is available. Therefore it minimises the chances of a difficult or dangerous cargo doing serious harm to the ship or those on board. No bulk cargo should be loaded and transported until those directly at risk are 100% sure it is safe to do so. That is why it is essential that all eleven links of the Chain are sound, and known to be sound. Even when it is outside the direct responsibility of the ship, each link has to be checked and tested. The IMSBC Code serves as the point of reference for this process, providing all the necessary information – not just a mandatory set of instructions, but a tool to help get the job done. Safely.
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FURTHER RESOURCES
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Bulk Carrier Practice, Nautical Institute Bulk Carrier Safety, Baltic and International Maritime Council (BIMCO) and Marine Technical Managers Association (MARTECMA) Bulk Carriers Safety Studies, Maritime and Coastguard Agency (MCA) Marine Information Note 228 (M) Code of Practice for the Safe Unloading and Loading of Bulk Carriers (BLU Code) IMO and the Safety of Bulk Carriers, International Maritime Organization Information Resources on Bulk Carrier Safety, International Maritime Organization International Association of Dry Cargo Shipowners (Intercargo) – www.intercargo.org International Convention for the Safety of Life at Sea (SOLAS), Chapter XII: Additional Safety Measures for Bulk Carriers International Grain Code International Code for the Safe Carriage of Grain in Bulk International Maritime Solid Bulk Cargoes Code (IMSBC Code)
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Manual on Loading and Unloading of Solid Bulk Cargoes for Terminal Representatives (BLU Manual)
Related training programmes from Videotel · Bulk Carriers – Handle with Care (Code 691) · Cargo Loss Prevention on Board Bulk Carriers (Code 598) · Entering into Enclosed Spaces Edition 2 (Code 628) · Hull Stress Monitoring (Code 550) · Safe Log Carrier Operations (Code 760)
