Cargo damage & claims:- Pre-shipment precautions for garlic in reefer containers

Cargo losses are very high in tropical countries, especially in the third world. The damage to reefer cargo is substantial where ambient temperatures are high, and losses in these regions can be as much as 30-35%. This is due to many factors including a poor transport infrastructure, absence of sufficient cold storage facilities, poor marketing infrastructure etc.

Dubai has recently seen a spate of claims in respect of alleged damage to consignments of garlic imported from China. The garlic market in Dubai is controlled by a limited number of traders, one of whom is the main importer of Chinese garlic. The Chinese harvest season runs from July to August. The cargo is imported either in bulk on reefer vessels or in reefer containers.

The quality and condition of the garlic is particularly affected by temperature and moisture, as well by gases like CO2 produced by respiration of the living cargo. Any problems can result in the deterioration and reduction of storage life of garlic exposed to abnormal and unwarranted changes in temperature. The storage life of garlic is typically 6-9 months depending on the storage conditions. The shippers and/or charterers should provide vessel interests with clear carriage instructions regarding the temperature, humidity levels and ventilation exchanges.

Carriage instructions and difficulties for the vessel

A feature of the recent cases is that vessel interests have accepted carriage instructions from the shippers/charterers, that create compliance difficulties for the vessel. For example, in one case the instructions were:

1. Holds pre-cooled to minus 5°C before loading
2. delivery air temperature of 0°C during loading
3. carriage temperature of minus 3°C
4. humidity 60-65% CO2 below 1%
5. air exchange minimum twice daily
6. a return air temperature of minus 3°C must be achieved within 3 days of the
completion of loading.

Apart from the requirements regarding monitoring and record keeping, these instructions caused a number of difficulties for the vessel, even with the refrigeration machinery working perfectly. Most notable is the difficulty posed by high pulp temperatures at the time of loading.

The pulp temperature is the temperature inside the garlic bulbs.

The cargo is brought from its place of harvest to the port in open trucks and is at times stored on the quayside without cooling for a long period prior to loading. Garlic can begin to sprout if damp, giving off heat in the process. In at least one case the pulp temperature at the time of loading was between 28°C and 32°C. Due to the high temperature of the goods at loading, the required return air temperature can be reached 9 days after loading and for some cargo spaces as long as 13 days after loading. The vessel will be unable to bring the temperature down to the necessary level in the agreed 3 day period.

The claims

A charter party will often require the charterer and consignee to be given daily temperature reports from the vessel. When the consignee finds that the temperature requirements have not been fully complied with, the ship is held responsible for any alleged damage to the garlic even before the vessel arrives at the discharge port. It is common practice to threaten the arrest of the vessel and to demand a guarantee as security for the claim.

The damage the Consignee often alleges to have occurred is `internal sprouting' of the garlic. Samples of the garlic will be cut at random and an allegation of an unacceptably high rate of sprouting is made. Consignees might allege that, if the carriage temperature is not maintained at minus 3°C, the sprouting will increase.

This results in a reduced storage/shelf life of the garlic, forcing the consignee to sell the garlic at a reduced price. The alleged loss is quantified either as a percentage of the invoice value by the Consignees' Surveyor or by producing sales invoices at a later stage. Claims often run in to hundreds of thousands of American dollars.

Clausing is the process of adding clauses or phrases to the bill of lading rather than issuing a clean B/L.

It can be difficult to defend these claims in the United Arab Emirates, particularly when a clean bill of lading has been issued. Vessel interests face the difficult burden of proving that problems with the garlic would not have been apparent at the time of loading and so clausing would not have been an option because the damage was due to inherent problems. In many cases, it is suspected that the real cause of damage is the high pulp temperatures prior to shipment. Vessel interests may be left with no other option but to negotiate a settlement on the best terms possible.

Vessel interests are advised to take special precautions when loading garlic, particularly in China, but also elsewhere where pre-shipment conditions are likely to cause problems when complying with carriage instructions. Among the precautions that vessel interests can take are:

1. Not to accept carriage instructions that the vessel is likely to have difficulty in complying with. In particular, the requirement of a return air temperature should not be accepted as it can depend on factors beyond the vessel's control, for example pulp temperature or quayside storage. Required carriage temperatures should only be accepted as delivery air temperatures as this is under the vessel's control.

2. The acceptance of carriage instructions, particularly under a charter party, should be on the express condition that the garlic is dry and that the pulp temperatures are within an acceptable range at the time of loading. Vessel interests can reserve the right to reject for shipment a non-compliant cargo and insist the charterers/ shippers have it dried and/or cooled before shipment.

3. If there is no alternative but to ship garlic with high pulp temperatures, an appropriate remark such as "shipped at pulp temperatures...at shippers risk without responsibility for loss or damage howsoever caused" could be inserted in the bill of lading

4. Shippers should be asked to provide information and evidence at the load port as to where the garlic originated from, how old it is and how it has been stored ashore. Failing this, vessel interests should seek to obtain the same. Photographs, including `close-ups' of the garlic, can be taken and records of weather conditions prior to loading should be kept.

5. Pre-shipment inspections of the garlic, with a view to clausing the bills of lading, should include any signs of rotting, staining and wetting. Packing should also be inspected, including a check to see if sufficient ventilation is provided. If there is no routine monitoring of the pulp temperatures and the vessel suspects these to be high, a surveyor can be instructed to attend on the vessel's behalf. His inspection can include a check for internal sprouting.

6. Tight stowage should be avoided as this makes it more difficult for the refrigerated air to circulate and for gases to be vented off.

7. Monitoring equipment should be calibrated and in full working order. Full and proper carriage records should be kept.

8. With the shipper's approval, a small sample of garlic can be placed in the vessel's own stores. The temperature monitoring and records could provide a useful comparison to the garlic in the holds, and may be important at a later stage.

Our detail pages below examine some typical cases of damage to reefer cargoes and countermeasures against poor information transfer and communication.

Cargo damage & claims:- Delivery of frozen cargo without Bills of Lading resulting a cargo claim

Whenever any cargo damage occurs, answers are sought as to why, where and when it occurred, reinforcing the commitment that whoever is responsible for damage is also accountable for it.

Liner agents took delivery of two discharged containers of frozen beef. The agents arranged for the two containers to be transferred to cold storage where they were stripped and the beef placed in storage awaiting delivery instructions.

A short time later, the storage company delivered the beef to a third party on the instructions of the consignee, without the bills of lading being surrendered. It was not until two weeks later that the agents became aware that the original bills of lading had not been surrendered and their enquiries revealed that the beef had already been delivered. At about the same time, the agents learned that the consignee had filed for bankruptcy.

A bill of lading (also referred to as a BOL or B/L) is a document issued by a carrier, eg a ship's Master or a company's shipping department. It acknowledges that specified goods have been received onboard as cargo for transport to a named place for delivery to the consignee, who is usually identified.

Lawyers advised that the agents' principals would be liable to the holders of the bills of lading for the value of the cargo, and that they in turn would have a good claim for indemnity against the agents for allowing the release of the cargo without ensuring that the bills of lading were first surrendered.

The value of the cargo was US$3,400. This was settled in full with the line and the shippers, in return for an assignment of their rights against the storage company and the notify party. Unfortunately after a full investigation, lawyers advised that a claim against the storage company was unlikely to succeed and there was little prospect of any recovery from the consignee's receivers.

Ironically, most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Most of these losses could have been avoided if appropriate checklists had been made and strictly adhered to, and the systems followed. Weak links in the chain of information need to be strengthened.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Contamination of a tank container of wine from Australia to the USA

Most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures.
A tank container with a shipment of 21,000 litres of wine was consigned from Australia to the USA. On arrival, the consignee refused to take delivery as the accompanying documents did not include the relevant certificate of food quality. It was also alleged that the wine was contaminated.

Arrangements were made for the tank container to be returned to Australia where tests could be carried out and, if necessary, the wine distilled to remove its alcohol content.

Enquiries revealed that the tank container had been used previously for a cargo of liquid detergent, and that a steam clean as well as the replacement of all the gaskets and seals to remove all traces of the detergent were necessary to bring the tank up to food quality standard. This had not been done and as a result the wine had become contaminated.

As a clean B/L had been issued the carrier had no defence against a claim from the shipper but the carrier in turn looked to the agent for indemnity under the terms of their Agency Agreement.

The tank container was ordered by the agent from a yard that was not used to dealing with tanks that were used for food and was unaware of the necessary food quality standards. The agent's written instructions to the yard specified the tank needed by container number, and also that it was intended to be used for the carriage of a cargo of wine, but the yard did not take any action to ensure that contents would not become contaminated. It was necessary for the agent to ascertain the previous contents of the tank from the import container files, but this was not done.

The liabilities of the shipper were investigated but, as an inspection of the tank before filling would not have revealed the presence of any liquid detergent residue within the seals and gaskets, these investigations were not pursued.

In due course, a claim for A $89,299 was made against the carrier. The Club decided to obtain their agreement from the agent, negotiating a settlement directly with the shipper to agree the best possible terms and to avoid any unnecessary costs. This was done and settlement was agreed at A$61,000. No costs were incurred.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Agents liability for reefer cargo damage survey at discharge port

Most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures.
A Lloyd's agent was instructed to carry out pre-shipment surveys on twelve consignments of frozen swordfish chunks. These were completed over a period of approximately four months. The buyer required that the agent warranted that laboratory tests were carried out prior to the shipment and that they had established that the mercury content was less than the permitted maximum in swordfish selected on a random representative basis.

The agent asked the State Laboratory to carry out the surveys. The correct number of cartons were opened, samples taken and the analysis report showed the mercury content was within the specifications. Unfortunately, the agent omitted to tell the laboratory that all the samples had to be analysed separately. The laboratory, in accordance with their normal practice, mixed the samples together and analysed only one or two composite samples. The wording of the agent's survey report also suggested that 5% of the cartons had been both sampled and tested.

On arrival in the United States the consignments were subjected to additional analysis by the US Authorities and the majority were found to contain mercury in excess of the permitted maximum. The cargo was rejected as being unfit for human consumption and the US importer suffered considerable financial loss, which was only partially covered by his cargo insurers.

Subsequently, the agent received a claim for US$1,000,000 from the importer and the club instructed lawyers to act for the agent and the club. Legal proceedings were commenced against the agent in the Californian Courts and the Club's San Francisco Correspondent was instructed to assist the Californian lawyers in the preparation of the defence.

Detailed investigations revealed certain information that was useful to the defence but the documentary evidence against the agent was difficult to dispute. An attempt to obtain a summary judgement to dismiss the claim against the Lloyd's agent was dismissed in California and the Club decided that a negotiated settlement was a better option. The negotiations were lengthy and protracted, but an agreement was finally reached where the claim was settled in the sum of US$412,500. Substantial costs were inevitably incurred amounting to US$247,727.

This claim is a reminder that the financial consequences of simple errors are impossible to foresee and highlights the need to carry the highest affordable level of insurance.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims :-Suitability of reefer containers, cargo damage due changing set-points & misinterpretation

Reefer containers are not designed to withstand ingress of water etc or left standing in water for long periods of time.Prior stuffing it is important to ensure that the locking bar is in order so that the doors can be closed properly. There should be no holes etc on the roof and side panels of the container. The container should be odourless and clean. Integrity of the container floorboard should be strong enough. The cargoes have to be properly packed and lashed within the container so as to prevent cargo movement during transportation. There should be an equal distribution of weight within the container. After stuffing, container should be closed properly and sealed.

Most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Most of these losses could have been avoided if appropriate checklists had been made and strictly adhered to, and the systems followed. Weak links in the chain of information need to be strengthened.

In Agfa Gevaert Inc v SS TFL Adams and Trans Freight Lines, refrigerated stowage carried in breach of the contract with the shipper was seen as an unreasonable deviation, preventing the carrier from relying on the package limitation under The Hague Rules and COGSA. This lapse had occurred as a result of the practice of carrying ordinary non-refrigerated cargo in reefer containers to maximise use, which led to mistakes occurring with cargo requiring refrigeration.

Change of Set-point Temperature resulting cargo damage

A case was reported where a reefer container temperature set-point was maliciously changed by one of the ship's officers as a result of internal multinational manning problems. Luckily, the change in set-point was noticed during the daily inspection rounds and serious cargo damage was prevented.


Cargo Damage due to Misinterpretation of `Frozen' and `Deep Frozen'

In this case, where a cargo of lobster tails were described by the shipper as `frozen', the carrier should have verified the actual condition of the cargo, which was deep frozen and therefore required to be kept at minus 18°C. The lower court held that the carrier was not responsible for products which should have been carried at minus18°C when the goods were shipped as merely requiring `refrigerated stowage' and the tariff rate was for goods that were frozen rather than deep frozen. On appeal the higher court found the carrier responsible, declaring that the carrier was a specialist who must enquire how the cargo should be carried, and should be alerted by the word `frozen' appearing on the bill of lading.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Failure to instruct cargo terminal resulting in reefer cargo damage

Any reefer cargo needs constant monitoring during transport to maximize product shelf life and ensure higher market value for products at destination market place.
Refrigerated container temperature control equipments that include reliable microprocessor controllers, controlled atmosphere, extremely low temperature containers, dehumidification, and environmentally friendly CFC (chlorofluorocarbon) free boxes. Selecting the right container for your cargo, ensuring correct stowing & securing practices, are critical . Whenever any cargo damage occurs, answers are sought as to why, where and when it occurred, reinforcing the commitment that whoever is responsible for damage is also accountable for it.

Importers of wine from France to the United States had previously encountered problems with consignments imported through New York during the winter months, when the wine could be subjected to sub- zero temperatures causing it to freeze and lose its quality.

In response to this problem, the line issued instructions that asked the agent to instruct the terminal operator to open the container as soon as it was delivered and place portable heaters inside to keep the temperature in the container above freezing.

Unfortunately, the agent failed to give the necessary instructions with respect to a cargo of nine containers of wine. While eight of the containers suffered no damage the carriers received a claim for US$120,000 for freezing damage to the remaining container.

A claim was made against the Agent, and after lengthy negotiations a satisfactory settlement in the sum of US$32,650 was agreed.

Ironically, most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Most of these losses could have been avoided if appropriate checklists had been made and strictly adhered to, and the systems followed. Weak links in the chain of information need to be strengthened.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Reason of frozen lobster damage in a reefer consignment

Whenever any cargo damage occurs, answers are sought as to why, where and when it occurred, reinforcing the commitment that whoever is responsible for damage is also accountable for it.

Action upon receiving reefer cargoes in a rotten / lost condition?

. Contact your insurance company if your cargo is insured and carrier and/or
carrier’s agent immediately to arrange for a joint survey.
. You are advised to cease unstuffing operations if damages/loss are found and
await instructions from the agent’s surveyor.
. Notice of damage/loss has to be lodged within three days upon taking delivery
of the container

Reason of frozen lobster damage in a reefer consignment

A liner agent employee in Taiwan booked a 20 foot reefer container of lobster from Keelung to Melbourne. When the stowage plan for the port of Keelung was prepared, due to a clerical error in the agent's office the container of lobster was shown as part of the general stow. As a result the container was off-power for the voyage and, on arrival at Melbourne, the entire cargo of lobster was declared a total loss.

The receiver claimed US$74,000 from the line, and the line claimed the same amount from its agent. Although it was initially felt that the line had failed to mitigate its loss and had paid too much, the Club paid the claim in full, after consulting lawyers. It is important to mention that the financial consequences of simple errors are impossible to foresee. In this instance the value of the cargo was US$74,000 but it could easily have been a much larger figure.

In 2007 it is unusual for a claim on a refrigerated cargo to be less than US $100,000 per refrigerated container. Ironically, most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Most of these losses could have been avoided if appropriate checklists had been made and strictly adhered to, and the systems followed. Weak links in the chain of information need to be strengthened.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Reefer cargo pre-shipment failure to provide suitable conditions or information

Whenever any cargo damage occurs, answers are sought as to why, where and when it occurred, reinforcing the commitment that whoever is responsible for damage is also accountable for it.
Action upon receiving reefer cargoes in a rotten / lost condition?

Contact your insurance company if your cargo is insured and carrier and/or carrier’s agent immediately to arrange for a joint survey.
You are advised to cease unstuffing operations if damages/loss are found and await instructions from the agent’s surveyor.
Notice of damage/loss has to be lodged within three days upon taking delivery of the container

Reason of frozen lobster damage in a reefer consignment

A liner agent employee in Taiwan booked a 20 foot reefer container of lobster from Keelung to Melbourne. When the stowage plan for the port of Keelung was prepared, due to a clerical error in the agent's office the container of lobster was shown as part of the general stow. As a result the container was off-power for the voyage and, on arrival at Melbourne, the entire cargo of lobster was declared a total loss.

The receiver claimed US$74,000 from the line, and the line claimed the same amount from its agent. Although it was initially felt that the line had failed to mitigate its loss and had paid too much, the Club paid the claim in full, after consulting lawyers. It is important to mention that the financial consequences of simple errors are impossible to foresee. In this instance the value of the cargo was US$74,000 but it could easily have been a much larger figure.

In 2007 it is unusual for a claim on a refrigerated cargo to be less than US $100,000 per refrigerated container. Ironically, most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Most of these losses could have been avoided if appropriate checklists had been made and strictly adhered to, and the systems followed. Weak links in the chain of information need to be strengthened.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Reefer cargo care - ships failure to maintain necessary conditions

A reefer ship is a type of ship typically used to transport perishable commodities which require temperature-controlled transportation, mostly fruits, meat, fish, vegetables, dairy products and other foodstuffs. There are cases where reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Below are examples of reefer cargo losses due ships failure to maintain necessary conditions .

Damage to Cases and Pallets of Oranges Shipped from Morocco to the US

A shipment of oranges was packed in cases then put onto pallets, each containing 63 cases, onboard the Reefer Express ship Ocean Rex. The pallets consisted of nine cases to a tier, stacked seven tiers high and secured by reinforced angles and nylon straps. The charter held the carrier responsible for the cargo until it was landed in the warehouse at the destination port.

The cargo was delivered to the vessel in apparently good order and condition, clean bills of lading were then issued. Although the Master filed a note of protest with respect to the delays in loading and the effect of these delays on the product's pulp temperature, he did not register a complaint with respect to the packaging, the handling by longshoremen or the onboard stowage. On discharge at New Bedford, USA significant physical damage was observed to a number of pallets, although the owner and charterer disagreed as to the extent and cause of them.

After discharge, the cargo was moved from the pier by forklift and flatbed truck to an adjacent cold storage warehouse, where it was stored in accordance with government regulations for fourteen days. The cargo receiver `Bacchus' claimed for $260,617, representing the depreciated value of the product, together with the survey fees and interest accrued, arguing that Reefer Express and its surveyor were unaware of the customary packaging of Moroccan oranges. It claimed that Reefer Express, having not raised a complaint about the packaging, loading or stowage, was precluded from asserting that the cargo was damaged during loading in Morocco or by heavy weather during the sea passage.

Reefer Express maintained that there were a number of possible causes of damage, for example pre-shipment condition and/or insufficient packing, heavy weather and negligent handling during the discharge to the wharf and the subsequent delivery to the warehouse.

The panel majority found that Reefer Express was liable for the damage to the cargo, awarding Bacchus US$218,246 in damages.

: Hyundai Fortune: Failure to Maintain the Required Temperature

The claimants were the owners of a cargo of Hami-melons that were loaded into a reefer container in Shenzhen, China. The reefer container was then loaded onboard the vessel Hyundai Fortune in Hong Kong for carriage to Singapore.

The melons should have been carried at a temperature of 3°C at all times. However, evidence was presented that the reefer container did not maintain the required temperature. According to the evidence, the temperature rose to 25°C during transit. As a result, the melons arrived at Singapore in a badly damaged state.

The claimants wrote to the ship owners demanding compensation, but the ship owners ignored their demands for almost a year. The claimants then commenced an action against the owners of the Hyundai Fortune in Singapore.

The ship owners applied to court to stay the proceedings in Singapore, by relying on the exclusive jurisdiction clause in the bill of lading, that referred all claims arising from or in connection with or relating to the bill of lading to the Seoul District Court in Korea. The High Court refused to stay the proceedings in Singapore after taking the following factors into consideration:

There was no defence on the merits of the claim
no trial would be held in Korea as the action had become time barred there
the connecting factors of the case were all related to Singapore
the overall justice of the case was with the claimants.

The ship owners appealed against the decision refusing a stay of proceedings in Singapore. Judgment: The ship owners' appeal was dismissed.

Deterioration of Banana Cargo due to Improper Ventilation

In Transatlantic Marine Claims Agency, Inc. v. S.S. Zyrardow, the carrier was found liable for the deterioration of a cargo of bananas after it had failed to follow the charterer's instructions stating that the storage holds should be ventilated sixty hours after the closure of the compartments to remove high levels of carbon dioxide and ethylene from the compartments, as this accelerates the ripening process.

Frozen Shrimp Damaged due to Failure of the Ship's Equipment

In AR Lantz Co, Inc. v. United Trans- Caribbean, the Court found that the vessel was not seaworthy to carry frozen shrimp as it was missing the necessary spare parts to maintain the refrigeration unit and one of the generators was inoperative, making the `vessel's refrigeration system unsuitable.' In making this decision, the Court followed the finding in Atlantic Banana Co. v. M/V Calanca, which found that improper maintenance and inoperative refrigeration equipment made the vessel unseaworthy.

Damage to Fruit Cargo due to Fire Damage to the Ship's Reefer Equipment

In Banana Services Inc v M/S Tasman Star, a fruit cargo was damaged when a fire onboard disabled the ship's refrigeration control panel, making it impossible to refrigerate the fruit properly. The Court found that the real cause of the loss was the fire which, although it did not ignite the cargo, nevertheless cleared the carrier from liability under the fire exception of section 4(2)(b) of U.S. COGSA(76) and the U.S. Fire Statute.(77).

Thaw Damage to Cargo of Frozen Orange Juice Concentrate

In Ins. Co. of N. America v. M/V Frio, involving thaw damage to a cargo of frozen orange juice concentrate, the carrier failed to establish either the defence of insufficient packaging or the exception of an inherent defect of the goods and was held liable as it had not rebutted the presumption resulting from the plaintiff's proof that the concentrate had been loaded in good condition and was discharged damaged.

Damage to Soybean Cargo due to a Lack of Ventilation

In Granite State Ins. Co. v. M/V La Pampa, the claimant proved that the carrier had failed to take all reasonable and necessary measures to prevent sweat damage to a cargo of soybeans and to ventilate the hold. The carrier was held liable for the entire loss under the Vallescura Rule, despite some evidence that the soybeans had a higher than normal moisture content on loading, because the carrier had "...not met the burden of showing what part, if any, of the damage is attributable to such a condition."

Damage to Cargo of Frozen Raspberries due to Improper Temperature Maintenance
The Court held a carrier responsible for thaw damage to a cargo of frozen raspberries as they were not kept at the contracted temperature throughout the voyage. In this case, the Court made it very clear that substantial proof must be presented in order to invoke the exception of act of the shipper under article 27(g) of Law No. 66-420 of June 18, 1966. In this case, a graph showing the internal temperature of the container throughout the voyage was not sufficient proof that the raspberries were not properly frozen at loading.

Improper Storage of Cheese in Unrefrigerated Warehouse

In M. Golodetz Export Co. v. Lake Anja and Italusa Corp. v. M/V Thalassini Kyra involving the alleged improper storage of cheese in an unrefrigerated warehouse after discharge, the Court noted that "the melting properties of a particular cheese is not a matter of common knowledge, that may reasonably be charged to the carrier." The carrier was not held responsible.

Damage to an Apple Cargo due to Non-compliance with the Shipper's Instructions

In See White & Son Ltd. v. White Star Line Ltd. the carrier did not follow the shipper's instructions for the care of apples. The carrier was held responsible.

Cargo damage & claims:- Reefer cargo losses due temperature failure & preventive measures

If inland transit time is greater than 2 hours for chilled cargo and 8 hours for frozen cargo, it is recommended to use the generator set to supply power to container during inland tracking . IF A GENERATOR IS NOT AVAILABLE, THEN IT is SUGGESTED THAT THE CONTAINER IS PLACED ON POWER FOR AT LEAST 6 HOURS PRIOR TO THE TRANSPORT . THIS WILL ALLOW THE MACHINERY TO EXPELL THE AMBIENT AIR THAT HAS ACCUMULATED INSIDE THE CONTAINER DURING LOADING. THUS THE PRODUCT TEMPERATURE IS STABILISED BEFORE TRANSPORT. FOR A 40 feet REEFER IT IS ESTIMATED THAT APPROXIMATELY 10 TO 13M3 OF AMBIENT AIR IS ACCUMULATED INSIDE THE CONTAINER.
Laden heat from external ambient may cause raise in carriage temperature if the reefer unit is left off power for too long. Hence it is always recommended to truck reefer cargo during cooler climate (at night) or with clip on generator set to ensure continue power supply during land transportation.






















Fig: Reefer container heating process

Incorrect Temperatures Maintained due to Poor Paperwork

The following reefer cargo claims resulted from errors made by the ship's agent when entering temperatures on the ship's documents or by inputting incorrect details into a computer.

Cheese from Denmark to the UK was carried at 0°C instead of minus 20°C. Concrete additives from Bremerhaven to Helsinki, which needed to be maintained at a temperature of +10°C to prevent frost damage, were carried at minus 6°C.

Bottles of wine from Antwerp to the US were carried at minus 20°C. Frozen beef was stored at +2°C as the temperatures for two reefers had been transposed by the Agent.

Incorrect Instructions for Reefer Temperature Setting

When the ambient temperature is warmer than the cargo, operating the reefer with the rear doors open will NOT cool down the cargo. The introduction of hot ambient air will heat up the cargo instead.

When hot humid air enters the reefer, moisture condenses on the cold cooling coil and turns to ice. Ethylene entering the reefer from genset exhaust may cause ripening of fresh produce. Exhaust odour may give product off-fl avours. Cooled air escapes out the rear door, and the cycle continues. Once loading is complete and the doors are closed the reefer could run for hours with a partially iced up cooling coil, reducing its cooling effect, and putting the cargo in danger until the unit completes a defrost cycle

A port agent in the UK received a container list from his principal's South American agent. This included two containers of frozen meat shipped at minus 18°C. When this information was transferred to the agent's computer system, the containers were shown as containing film with a temperature setting of +13°C.

Unfortunately, the error was not picked up even after additional checking, with the result that when the containers were discharged at the UK port they were set to +13°C in accordance with the agent's instructions. Three days after arrival at the container depot, blood was seen seeping from the doors of the containers, these were then opened to reveal the rapidly thawing beef.

The temperature control was re-set to minus 18°C to try to stabilise the consignment. Surveyors were immediately instructed by the carrier's P&I Club, and the Port Health Authority issued notices stating that the consignment could not be used for human consumption. An offer was accepted for salvage, this reduced the claim against the agent and was settled by the Club.

Our detail pages below examine some typical cases of damage to reefer cargoes & countermeasures against future claims

Cargo damage & claims:- Reason of reefer cargo losses ,damage investigation & preventive measures

In commerce and manufacturing, there are many uses for refrigeration. Refrigeration is used to liquify gases - oxygen, nitrogen, propane and methane, for example. In compressed air purification, it is used to condense water vapor from compressed air to reduce its moisture content. In oil refineries, chemical plants, and petrochemical plants, refrigeration is used to maintain certain processes at their required low temperatures (for example, in the alkylation of butenes and butane to produce a high octane gasoline component). Metal workers use refrigeration to temper steel and cutlery. In transporting temperature-sensitive foodstuffs and other materials by trucks, trains, airplanes and sea-going vessels, refrigeration is a necessity.
Dairy products are constantly in need of refrigeration, and it was only discovered in the past few decades that eggs needed to be refrigerated during shipment rather than waiting to be refrigerated after arrival at the grocery store. Meats, poultry and fish all must be kept in climate-controlled environments before being sold. Refrigeration also helps keep fruits and vegetables edible longer. Cargo losses are very high in tropical countries, especially in the third world. The damage to reefer cargo is substantial where ambient temperatures are high, and losses in these regions can be as much as 30-35%. This is due to many factors including a poor transport infrastructure, absence of sufficient cold storage facilities, poor marketing infrastructure etc.

Whenever any cargo damage occurs, answers are sought as to why, where and when it occurred, reinforcing the commitment that whoever is responsible for damage is also accountable for it.

Ironically, most reefer cargo damage occurs not because of technical reasons, but due to poor communication systems, management practices or administrative procedures. Most of these losses could have been avoided if appropriate checklists had been made and strictly adhered to, and the systems followed. Weak links in the chain of information need to be strengthened.

ITIC (International Transport Intermediaries Club) Claims Review reports that there have been an increasing number of claims (varying between US$15,000 and $150,000 in value) resulting from reefer containers either being left unplugged at the load or discharge port or being carried at the incorrect temperature.

Documents are fundamental in the investigation of a claim involving damage to cargo. They will be examined by the technical surveyors and may be used as evidence in subsequent legal proceedings. The following documents are likely to be important in the event of a claim:

Ship's log
bill of lading
Mate's receipts and attached record of the inspection of the cargo prior to and
during loading
deck log of loading and unloading
stowage plan
engine room log
any documentation arising from disputes during unloading and/ or the receipt of
cargo.
Photographs and video recordings can provide crucial additional evidence to
support statements in the logs and inspection reports.

It is important to understand how to keep cargo fresh . Ensure that your cargo travels in an unbroken cold chain from the point of origin to the final destination, in close coordination with leading reefer container carriers and service providers. Any observations that indicate the cargo temperature is high or that the cargo was delivered in a damaged or deteriorated condition should be supported, if possible, by further evidence. This evidence might include photographs taken during the pre- shipment inspection or results of reports by cargo surveyors.

As soon as any question is raised over the condition of the cargo, the ship's Master should begin to document the events surrounding the discovery of the defective material, along with the nature and possible extent of the alleged defects.

If possible, loading or unloading of the vessel should be halted and the hatches closed until a cargo surveyor is present. Ideally, the cargo should be inspected and sampled while it is still in the hold or during discharge. This will allow the surveyor to determine the nature of the damage and whether it is related to its position in the hold.

Once the cargo has been discharged into the store, the process of relating any damage to its location in the hold is more difficult. This can be impossible unless the cargo is adequately labelled. Therefore, if loading or unloading must continue, the Master should ensure that as it leaves the hold each cargo unit is labelled with the hatch number and deck as well as its location. The deck log should also record the destination of the material and the agent responsible for handling it.

When a problem is identified during loading or unloading, for example if the temperature of the cargo is too high, loading or unloading should stop until the cargo has been inspected by a specialist surveyor. If the dispute concerns the quality of the product, it will probably be necessary for at least one specialist surveyor to examine the cargo to establish its current quality and determine the nature and cause of any defects.

If it is suspected that the defects result from maritime causes, an expert in ship operations should assess, for example, physical damage from movement of the cargo or from contamination with seawater, fuel oil or bilge water. If the defects can be attributed to the initial quality of the material when loaded or to the way the product was stowed and carried onto the vessel, a specialist surveyor is necessary.

Specialist reefer surveyors offer customised reefer solutions, ranging from single corridor port-to-port to multiple corridor door-to-door solutions with full end-to-end visibility. Many of the surveyors appointed by local shipping agents are general marine surveyors, often with a seagoing background. They are not necessarily skilled in the evaluation of, say, the quality of fish cargo. Masters and agents are advised to check the expertise and qualifications of the surveyors carefully to ensure that their technical background and experience are appropriate for the particular job.

As a general rule a single surveyor should not be commissioned for both a cargo survey and a survey of the vessel's condition. Since the skills required for each type of assessment are different, it is unlikely that one person would have experience in both areas at the levels of expertise required. For example, a fish cargo surveyor should have a background in food science and experience in the inspection of food products, ideally in assessing the quality of frozen fishery products.

Our detail pages below examine some typical cases of damage to reefer cargoes and countermeasures against poor information transfer and communication.

Purfresh Technology

How It Works

Based on patent-pending technology, Purfresh® Transport is an active cargo protection system that uses an active form of oxygen—commonly referred to as ozone—to kill molds, yeasts, and bacteria in the air and on surfaces by up to 99%, as well as to consume and regulate ethylene levels. After doing its work, the ozone immediately reverts to pure oxygen, leaving the product’s taste, texture, and smell characteristics in their natural state.




To optimize freshness and manage the container’s atmosphere during the entire trip, Purfresh Transport intelligently reacts and adjusts to changes in the organic load of the cargo (such as microbes, VOCs, and ethylene levels) and changes in the environmental conditions (such as temperature).




Certified organic and approved by the USDA and FDA, Purfresh Transport delivers what no other solution can—a chemical-free approach to extending shelf life, minimizing waste, and maintaining the quality of fresh produce during long-range transport.






Equipment

Purfresh® Transport units are easy to install, operate, and maintain. The unit simply mounts into the existing evaporator fan access panel and can be operational in as little as 15 minutes.
Much simpler than traditional CA/MA shipments, Purfresh Transport does not require airtight environments or curtains, nor does it take up cargo space inside the container.
In addition, Load Protection Monitoring™ (LPM™)—an optional feature of Purfresh Transport—provides complete environmental monitoring, including temperature, relative humidity, carbon dioxide, oxygen, and ozone, as well as the location of the container via GPS tracking. With this level of en route visibility, LPM can help you avoid catastrophic loss by being able to quickly identify problems (such as closed vents) and take the appropriate action before it’s too late to save the load.








Monitoring and Tracking

A next-generation informatics service, Intellipur® from Purfresh provides unparalleled visibility into, and control over, refrigerated marine container atmospheres, as well as global location tracking. Designed to enhance the value of Purfresh® Transport, the Intellipur information service provides real-time visibility into atmospheric conditions inside the reefer, location data, and exception alerts, as well as detailed trip reports.

Reefer journal: Container Refrigeration Temperature Recording Systems (Part 1)

By C. Maheshwar
Faculty, Training Ship Chanakya
Navi Mumbai

C.Maheshwar is a marine engineer, from Marine Engineering College, Kolkata, (DMET) 1980. He has sailed on board foreign - going ships of Shipping Corporation of India Ltd., from 1980 to 1997, the last 5 years of which were as chief engineer officer. Ashore, he has worked from 1997 to 1999 with the Taj Group of Hotels as chief engineer of Taj Connemara Hotel, Chennai, and as customer service manager, Reefer Container Group of Carrier Transicold for the region of South Asia from 1999 to 2001. Currently, he is working as engineering faculty at TS Chanakya, Navi Mumbai, a Merchant Navy Training Institute, belonging to the Govt. of India and affliated to University of Mumbai and IGNOU. He is a consultant for Anglo-Eastern Maritime Training Centre and conducts training programmes on reefer containers for seagoing engineers on a regular basis. He can be contacted at cmaheshwar@hotmail.com

This is the first of a series of articles on container refrigeration. These articles are intended to familiarize the reader with the basics of containerization, and will lead the reader through the complexities of the design and usage of refrigeration equipment when fitted on containers. This article in particular will deal with an introduction to containerization as a concept, container refrigeration, its evolution and commercial aspects. Subsequent articles will deal with various other aspects of interest to HVACR engineers.

Refrigerated containers will be henceforth referred to as reefer containers. It is to be understood that merely reading of these articles will not make the reader an expert or an authority on reefer containers and practical knowledge is essential. When working on any particular make or model of equipment, the appropriate Instruction Manual is to be consulted and instructions to be followed.

It is assumed that the reader is already familiar with the basic concepts of refrigeration.
Introduction to Containerization

Containerization dates back to the early 1950s. As the worldwide shipping trade grew by leaps and bounds, conventional break bulk cargo has been slowly replaced by containers. Commercial pressures and competition forced companies to reduce their cost of operations. This had a direct impact on the advanced countries where the cost of labour was more than the cost of technology. The cargo loading and unloading labourers get paid in dollars on an hourly basis with extra incentive in the form of overtime for working on weekends and holidays. There was an urgent need to bring down the labour component involved in cargo operations.


Additionally, cargo pilferage and losses were not accepted and tolerated any more. Shipping lines had to discharge the exact amount of cargo at the discharge port that was loaded on the ship at the loading port. The allowance due to loss/pilferage of cargo was drastically reduced. Further, the same conditions applied for the cargo during its onward journey from the discharge port to its final destination.

Unitization of cargo became an important concept for bringing down the labour costs. Pre-slinging of cargoes, palletization, containerization, barge-carrying ships, Ro-Ro ships are all examples of the unitization concept. Containerization was the need of the hour. Containerization became the most effective and efficient method of cargo handling. With containerization, per capita labour output improved dramatically.

A container is a box of internationally accepted standard dimensions. The standard sizes recommended by ISO (International Standards Organization) are 20ft (length) × 8 ft (width) × 8ft (height) and 40ft (length) × 8ft (width) × 8ft (height). The former was known as a TEU (Twenty Foot Equivalent Unit) and the latter was referred to as FEU (Forty Feet Equivalent Unit). One FEU is equal to two TEUs. Generally the capacity of a container ship is referred to in terms of TEUs. In addition to the above two sizes, the height may be also 8' 6." The length may also be 45 ft.

Material of Construction: The sides, roof and floor of a container may be made up of Steel, Stainless Steel, Aluminium, Fiberglass, Plywood, etc., depending upon the application. The structure is generally made of steel.

Features of a Container

1. It is of a permanent character, strong enough for repeated use.
2. It is designed to facilitate the transport of goods from one mode to another, i.e., from road to sea or rail to sea without intermediate reloading.
3. It is designed for easy stuffing and destuffing.
4. It is fitted with facilities to permit easy handling and transferring from one mode of transport to another.

Advantages of Container Transportation

1. Faster and reliable delivery
2. Greater protection of fragile and easily contaminated cargoes
3. Ensures original quality of goods
4. Reduces pilferage
5. Enables Physical seperation of dirty cargoes
6. Simplification of documentary procedures
7. Reduction in cost of cargo handling and ships' stay in ports.
8. Reduction in packing cost to the shipper.

A container has a strengthened deck (floor) and corners. The floor is lined with wood. The sides are corrugated to provide strength as the sides and roof of a container are highly susceptible to damage. The main strength of the container lies in the frame. The ICSC (International Convention for Safe Containers) specifies structural requirements for containers and contains regulations for inspection, approval and maintenance of containers. Most containers are built with fork lift pockets.




Types of Containers

1. Closed box or general purpose containers most commonly used for various types of cargoes.
2. Open sided containers which can be loaded from either side forward or aft and have hatch covers that drop down on either side.
3. Bulktainers (Dry bulk containers) have loading hatches in the roof and one or more discharge hatches
4. on the sides. Tanktainers (Tank Containers) are used for carrying bulk liquids.
5. Half height containers are normally used to carry high density cargo.
6. Reefer containers are used to carry refrigerated cargo and are equipped with refrigeration machinery.
7. Other special types are Pen Containers for livestock, Tiltable Containers for grain, Open Top Containers, Collapsible Containers, End Open Containers for carrying long cargo, Fantainers which are equipped with fans or blowers to blow air through the cargo, Hangtainers, which have hangers used for carrying garments and so on.

Refrigerated Containers

A refrigerated container (reefer container) is a container in which temperature can be maintained within certain limits that correspond to the storage conditions required for certain types of cargoes. They can be of two types – the Individual System in which the container is equipped with its own individual refrigerating machinery and the Collective System, in which a separate refrigerating source handles the distribution of cooling to a group of containers which is generally a permanently fitted refrigeration equipment on board the ship or a portable unit which is fitted on a temporary basis on the ship for that voyage or a charter connecting to a group of cargo carrying containers.

Question: By looking from outside, how can we make out if a container is a refrigerated container?

A. Yes, we can identify a reefer container from its external appearance, At the front end of the container, look for the presence of the refrigeration machinery. Also, the sides of a reefer container are smooth due to the external aluminium sheeting, where as, a normal GP (General Purpose) container will have corrugated sides made up of steel sheeting. The corrugations provide additional strength and stiffening to the container. A refrigerated container has external aluminium sheeting and internal stainless steel sheeting. There are intermediate strengthening vertical members spaced evenly apart. The space between the internal and external sheets is filled with insulating material, generally poly urethene foam (PUF) which is injected between the two layers at high pressure displacing air through vent holes at the top.

Question: Does the size of the container increase because of the additional refrigeration equipment?

A. No, the refrigeration equipment is fitted within the overall standard dimensions of the container, i.e., 40 × 8 × 8 ft or 20 × 8 × 8 ft. Some of the cargo carrying space is utilized to accommodate the refrigeration machinery. This is known as the picture frame type reefer container. Most of the marine reefer containers are of this type. This is because of the availability of limited space within the ship and the need to carry maximum number of containers requiring optimization of space. The other type of reefer containers are Over Hanging type in which the refrigeration equipment projects beyond the overall standard dimensions of the container. These are generally used ashore for over land transportation of the containers by trailer or rail.

Question: What about the power supply for the refrigeration machinery?

A. Generally power supply is taken from the ship's main power supply when the container is on the ship. While in port, the shore power supply is utilized to run the refrigeration machinery. When transporting across land in a truck, trailer or a train, power supply is generally taken through a genset from the main prime mover of the truck or trailer or main power supply of the freight carrying train. In some instances, an additional genset is permanently installed between the container trailer chassis and the driver's cabin. Some of the containers are installed with clip-on gensets which are dedicated to supply power only to the refrigeration machinery. These clip-on gensets can be removed when not required. Some of the older containers had gensets permanently fitted within the picture frame of the container. The genset with its own fuel tank occupied the lower half of one end of the container and the refrigeration machinery occupied the upper half.

Question: What about the extra power required for the reefer containers from the ship's main power supply?

A. Yes, the ship's main power supply should be able to cater to the extra load due to running of the reefer container machinery. Generally the ship's power supply will be designed after taking into consideration the maximum number of reefer containers it can carry at a time. However, if required, an additional generator is installed on board the ship exclusively to cater for the extra load due to running of the reefer container machinery.

Question: What about the extra deadweight, loss of volumetric space and the extra maintenance required for to the reefer container machinery?

A. Yes, the extra deadweight due to the reefer machinery results in a loss of freight for the ship. Similarly, a reefer container requires a lot of inspection and maintenance during the voyage which is a downtime equivalent of 1% per day. Similarly, there is a considerable loss of volume of cargo space which is required not only for the location and efficient functioning of the refrigeration machinery, but also for sufficient access space around the machinery for regular inspection and repairs if required. But all these factors are compensated more than adequately as the freight for reefer containers is much higher than a normal container. In fact, any shipping line will run after a reefer cargo and will be willing to carry out necessary modifications in the ship and providing additional machinery for power generation and other fixtures.

Question: What about the heat given out from the condenser of the refrigeration equipment?

A. Yes, a lot of heat is given out by the condensers, in fact, whatever heat has been removed from the inside of the container through the evaporator is given out by the condenser. When the reefer containers are stored on the deck in the open air, the heat from the condensers is discharged into the atmosphere. They use air-cooled condensers.

Question: Does it mean that they can store loaded reefer containers only on the deck?

A. No, not necessarily. Reefer containers can also be stored inside the cargo holds. But the heat given out by the condensers of all the running reefer containers inside the cargo hold should be led outside efficiently. Otherwise, there will be heat accumulation inside the cargo hold and the refrigeration machinery will not function efficiently. That means the ship's cargo hold ventilation system should be so designed to allow the required number of air changes so as to maintain the temperature inside the cargo hold within the permissible limits. Alternatively, they may use water-cooled condensers. In such a case, the cargo hold should be equipped with water circulating system with pipelines running along the sides of the cargo hold which can be connected to the individual reefer containers through a pair of flexible pipes – one for the inlet and the other for the outlet. Often, such containers are marked "IN HATCH STOWAGE ALLOWED". By looking at a reefer container, by noticing the water-cooled condenser inlet and outlet water pipe connection couplings, we should be able to determine its suitability for storage inside the cargo hatch. Generally, all reefer containers are equipped with air-cooled condensers, water-cooled condenser, if fitted, is an additional optional feature. It implies, that all reefer containers are by default designed to run as air cooled units. However, some of them are also designed optionally to run as water-cooled units.

Question: Can a reefer unit run as air-cooled and water-cooled unit at the same time?

A. No, to improve the heat transfer across the condenser coil, all reefer units are provided with a condenser fan. When fitted with an optional water-cooled condenser, and running as a water-cooled unit, the condenser fan cuts off when sufficient water pressure is available in the water pipelines of the water-cooled condenser – a pressure switch switches off the condenser fan and switches it on at low water pressures. In older units, there was a manual toggle switch which could be operated if water-cooled condenser was connected and was in operation.

Question: Does it have any bearing on the loading of the containers on the ship?

A. Yes, it should be noted that no two reefer containers should be loaded with the machinery facing each other. The hot air discharge from each of the condensers will enter the condenser of the other unit, affecting the performance of both the machineries adversely. Also, even when two reefer containers are loaded with their machinery not facing each other, enough space should be left near the condenser of each unit so as to facilitate free flow of air to and from the condenser, otherwise the performance of the machinery will be affected adversely.

Evolution of Container Refrigeration

Refrigerated containers have been employed on ships since more than 40 years. The earlier versions had only the basic components and a very narrow range of temperature applications. Setpoint could not be changed at will and even if it could be changed, the arrangement was very crude using a potentiometer arrangement. There was little scope for changing the defrost interval. There were no low voltage components resulting in lot of heat generation and power consumption. There were very few alarms and safeties, thus safety of the cargo, machinery and personnel was not ensured. There was no fool-proof and tamper-proof temperature recording mechanism, the only one which was available was a mechanically moving paper chart powered by a hand wound clock mechanism. There were frequent breakdowns caused by mechanical failures of components. Instances of cargo damage were high resulting in huge cargo insurance claims. Reefer container machinery has come a long way over the last 40 years and has evolved brilliantly. Each of the components has undergone a metamorphosis. Present systems are power efficient with foolproof and tamperproof recording, back ups for all important components, advanced warning systems in the form of alarms and cutouts, increased reliability of components resulting in enhanced safety of cargo, machinery and personnel. Now, with Remote Monitoring Modems and Radio Frequency Identification Systems, it is possible to monitor the performance of each reefer container from a shore office continuously and perform necessary adjustments
Commercial Aspects of Reefer Containers

Today, a 20 feet Dry (General Purpose) container box costs about US$ 2000. A reefer container consists of two distinct components – the refrigeration machinery and the box. The refrigeration machinery with standard features costs about US$ 10,000. A 20 ft. reefer box costs about US$ 5,000. The major reefer machinery manufacturers are Carrier, Thermo King, Daikin, Mitsubishi etc. The major reefer box manufacturers are Freuhauf, CIMC, Moon, GE, Transafe, Balmer Lawrie, etc. When a reefer container has to be bought, the orders are placed separately on the box manufacturer and the machinery manufacturer. The machinery manufacturer delivers the machinery at the location where the box is manufactured. The machinery is fitted on to the box , tested and the unit commissioned and delivered to the customer's representative by the machinery manufacturer's representative in the presence of the box manufacturer.
References

1. Cargo Work for Ship's Officers by Capt. Errol Fernandes.
2. Trends in World Seaborne Trade and Shipping-Present and Future by Dr. K V Hariharan.
3. Container Manual by Shipping Corporation of India
4. Marine Refrigeration Manual by Capt. AWC Alders.
5. www.carrier.transicold.com
6. www.thermoking.com
7. www.mhi.com
8. www.daikin.com

Reefer journal: Container Refrigeration Temperature Recording Systems (Part 2)

By C. Maheshwar
Faculty, Training Ship Chanakya
Navi Mumbai
Technical Advisor

C.Maheshwar is a marine engineer, from Marine Engineering College, Kolkata, (DMET) 1980. He has sailed on board foreign - going ships of Shipping Corporation of India Ltd., from 1980 to 1997, the last 5 years of which were as chief engineer officer. Ashore, he has worked from 1997 to 1999 with the Taj Group of Hotels as chief engineer of Taj Connemara Hotel, Chennai, and as customer service manager, Reefer Container Group of Carrier Transicold for the region of South Asia from 1999 to 2001.

Currently, he is working as engineering faculty at TS Chanakya, Navi Mumbai, a Merchant Navy Training Institute, belonging to the Govt. of India and affliated to University of Mumbai and IGNOU. He is a consultant for Anglo-Eastern Maritime Training Centre and conducts training programmes on reefer containers for seagoing engineers on a regular basis. He can be contacted at cmaheshwar@hotmail.com

In this issue, we will examine the various types of refrigerated cargo and the implications of the different types on the performance and operation of container refrigeration machinery.

Question : What are the various types of cargo that can be carried in a refrigerated container?

A. Refrigerated cargo carried in reefer containers can be classified as food items and non-food items. Examples of food items are fruits, vegetables, meat, fish, beverages, dairy products, ice cream, etc. Examples of non-food items are chemicals, explosives, leather, photo films, medicines, vaccines etc.

More importantly, refrigerated cargoes can be classified as chilled cargoes and frozen cargoes.

Chilled cargoes are those cargoes which are stored above –10°C. They are live cargoes with chemical reactions and processes going on within the product due to respiration, with continuous liberation of gases and heat. Chilled cargoes are also known as “perishable cargoes” in refrigeration parlance.


Frozen cargoes are those cargoes which are stored below –10°C. They are dead cargo, with no chemical processes or reactions taking place within the product and no liberation of gases or heat.

Chilled cargoes are temperature sensitive cargoes. The heat generated by the chemical reactions has to be led outside the cargo space faster than it is liberated to prevent any accumulation of heat and rise of temperature. Similarly, gases which are liberated as products of the chemical reactions have also to be drawn out of the cargo space, if found unsuitable for the cargo. Otherwise the cargo might deteriorate and get damaged. Chilled cargoes are generally fruits and vegetables, dairy products, chilled meat, beverages etc.



The temperature of chilled cargo needs to be maintained within a very narrow band of ± 0.5°C around the set point. Variation of temperature beyond this may enhance chance of cargo deterioration.

Myth: For all refrigerated cargoes, the lower the temperature, the better it is for the preservation of cargo.

Reality: For chilled cargoes, temperature must be maintained very close to the set point. If the temperature is allowed to fall lower than the set point, cargo damage may occur because of overcooling of cargo. Frozen cargoes do not get damaged even if temperature goes below the set point for prolonged periods of time. Instead of –20°C, if we maintain the temperature of ice cream at –25°C, it does not cause any damage or deterioration to the cargo. For frozen cargo, as there is no evolution of heat from the cargo, it is much easier to maintain the temperature.

Whenever there is a power breakdown or a planned and purposeful shutdown, it must be remembered that chilled cargoes are more vulnerable for damage and deterioration due to heat generation and accumulation inside the container resulting in temperature rise. Frozen cargoes do not get damaged because the temperature rise is very slow as there is not heat generation from the cargo. So, whenever possible, all chilled cargo reefer containers should be clustered together and connected to one power source or circuit breaker. Power should be restored as soon as possible for chilled cargo containers. Power to the frozen cargo containers can be restored later after all the chilled cargo containers have been activated.


Image 2

Question : Does the reefer machinery perform in the same way for both the chilled and frozen types of cargoes?

A. Obviously not. The refrigeration machinery behaves differently for chilled and frozen types of cargo.

Chilled Cargoes. When the set point temperature desired for the cargo is set to above –10°C, and the machinery connected and started, modulated cooling takes place, i.e., as the temperature inside the cargo chamber gets closer to the set point, the amount of refrigerant passing through the refrigeration circuit gets reduced, the additional refrigerant which is not under circulation gets stored in the receiver. When the temperature inside the cargo space reaches 0.2°C below the set point, the cooling is stopped. This is achieved by stopping the condensor fan and the compressor with a signal from the controller when a difference of 0.2°C is sensed between the set point and the actual temperature measured inside the container. This is a proactive step by the controller to prevent the temperature from falling far too much below the set point as chilled cargo will get damaged at temperatures much below the set point. The evaporator fans continue to run without the cooling circuit, circulating the same uncooled air and help in stabilizing the temperature closer to the set point due to heat generation from the cargo.

In case, the temperature of the cargo continues to fall further because of the momentum of the cooling cycle and the time taken for the temperature to stabilize along the entire length of the container, when the temperature reaches 0.5°C below the set point, the controller decides that the temperature must be prevented from falling any further, as a proactive step it activates the electric heaters. This is done by closing a heater relay inside the controller circuit, which energises a heater contactor and allows high voltage to flow through the heater coils. Since the evaporator fans are already running, hot air will be circulated through the cargo space inside the container.

As the temperature inside the container starts rising, when the temperature reaches 0.2°C below the set point, the heaters are stopped and only the evaporator fans are kept running. As the temperature continues to rise further, due to the heat generation from the cargo, once the temperature inside the container reaches 0.2°C above the set point, the cooling circuit gets activated through closing of the appropriate relays in the controller circuit, and the compressor and the condensor fan start running. The idea is to initiate proactive steps to keep the temperature of the cargo inside the container as close to the set point as possible, 0.2°C and 0.5°C being the limiting values.

Frozen cargoes. When the set point temperature desired for the cargo is set to below –10°C, and the machinery connected to power and started, nonmodulated cooling of the space takes place with the refrigerant flow kept fully (100%) in circulation through the refrigerant circuit. When the temperature reaches 0.2°C below the setpoint, as in the case of chilled cargoes, the cooling circuit gets switched off with the signal from the controller stopping the compressor and condenser fan. Only the evaporator fans continue to run. The evaporator fans continue to run until the temperature starts rising and reaches 0.2°C above the set point, when the cooling circuit gets activated again. In frozen mode, the heater coils do not get energized at all. The logic for this is that even if it takes longer time for the temperature to come closer to the set point or even if the cargo temperature falls below the set point for a prolonged period of time, cargo does not get damaged. So, the heater circuit need not be energized, thus achieving a saving in power.



Frozen cargoes run on non-modulated cooling so that the temperature can be brought down to the set point as soon as possible and saving power by cutting off the cooling circuit. It does not damage the cargo even if the temperature is lower than the set point for prolonged periods of time.

Evaporator Fans

Generally, there are two evaporator fans for a reefer container. Both of them are dual speed fans. Both of them run either at low speed or at high speed. (It is not possible to run one of the evaporator fans at low speed and the other at high speed). The running of the evaporator fans is controlled by two contactors with each contactor allowing power to be sent to both the fans either to low speed coils or to the high speed coils of both the evaporator fan motors.

Question : Is this cut-off temperature of –10°C between chilled cargoes and frozen cargoes sacrosanct? There may be some cargoes which are stored at more than –10°C and yet behave like frozen cargoes. How does the equipment treat and handle such cargoes – chilled or frozen?

A. Yes, there may be such cargoes which may be stored at more than –10°C, yet they may be frozen cargoes. The distinction point of –10°C is set as default by most of the manufacturers of reefer container machinery to control the operating logic of the various components. However, there is an option provided to change this setting from –10°C to –5°C. That means certain cargoes which are stored above –10°C, but below –5°C can be treated as frozen cargoes and the machinery will apply the logic of frozen cargoes.

Question : Why are two speeds required for the evaporator fans and when are the two different speeds used?

A. When carrying chilled cargo, both the evaporator fans run at high speed and when carrying frozen cargo, they run at slow speed.

Since chilled cargoes are temperature sensitive cargoes, as we need to maintain the temperatures within a very narrow range of ± 0.5°C, and as they are live cargo generating heat continuously, unless the heat generated is drawn away from the cargo space faster than it is generated, there will be heat accumulation and consequent cargo damage. To facilitate faster removal of the evolved heat, evaporator fans run at a higher speed.

Since frozen cargoes do not generate heat being dead cargoes, and cargo does not get damaged or deteriorated in spite of storage at temperatures much below the set point for prolonged periods of time, evaporator fans are run at lower speed, saving some power in the bargain.

Question : Where is the temperature measured inside the cargo space? Is there any difference in measuring points for the two different types of cargo?

A. The temperature sensors are located before the evaporator fans and are called “return air (temperature) sensors” and the ones after the evaporator coil are known as “supply air (temperature) sensors”. Usually, with a normal running container machinery, there exists a temperature difference of 2-3°C between the supply temperature and the return temperature, the supply being always cooler than the return as it is after the cooling effect of the evaporator. The circulation of the cold air from the evaporator coil is through the bottom of the container. The hot air from the cargo being lighter tends to rise to the top of the container. The suction to the evaporator fans is from the top. The evaporator fans force the air downwards through the evaporator coil, cooling the air and the cold air and passes eventually through the bottom of the container. To facilitate the flow of cold air across the entire length of 20 ft. or 40 ft. of the container, the evaporator fans are designed to provide sufficient air throw. Further facilitation of the same is provided by the T bars in the floor. Cold air passes through the spaces between the T bars and travels right till the end of the container. Cargo is placed on top of the T bar floor and even spacing of the cargo allows cold air to pass through the cargo and cool the cargo. It is important to keep the spaces between the T bars clear, otherwise there will be obstruction to the flow of cold air. Dunnage, paper, plastic and other packing material may block the passage between the T bars.


When carrying chilled cargo, the supply air temperature sensor acts as a controlling probe and when carrying frozen cargo, the return air temperature sensor acts as a controlling probe. This implies that in chilled mode, the temperature at the supply sensor acts as the controlling point to initiate cooling circuit, heating circuit or to run only the evaporator fans. Since at no point of time, any part of chilled cargo should be exposed to cold air at a temperature lower than the set point, the temperature at the supply side is the limiting factor. For frozen cargo, return temperature sensor is the controlling probe because the temperature of the cargo can be brought down below the set point without causing damage to the cargo. Hence temperature of the cargo will be brought to the set point and maintained with lesser running of the cooling circuit achieving significant saving in power.

Question : What about the packages of chilled and frozen cargoes? Can they both be both identical?

A. No. For chilled cargoes, each piece of the cargo (fruit or vegetable) has to be cooled by exposing it to the cooled air. Each piece of the cargo should be wrapped in material which can allow cold air to pass through. Generally, each piece of cargo is carried in plastic net or thin porous paper. Chilled cargo pieces should not be wrapped in completely enclosed plastic wrapper as plastic is an insulator. A totally sealed plastic wrapper does not allow the cargo piece to breathe. After a short passage of time, there will be a deficiency of oxygen and an excess of carbon-dioxide and accumulation of heat and gases like ethylene being liberated from the cargo because of ripening. If plastic is used as a wrapping material, it must have sufficient holes to allow the cold air to touch the cargo piece, and to allow breathing of each individual piece of cargo.

The cardboard or wooden boxes in which each individual piece of cargo is packed should not be air tight and a fully sealed container. They should have sufficient air holes all around the sides to allow cold air to pass through and cool each individual piece of cargo.

The same logic holds good for frozen cargo. The cold air should be allowed to touch the individual pieces of cargo. However, since frozen cargo does not generate heat nor gases as it is not a live cargo, the individual pieces of cargo may be packed in fully sealed air tight wooden or cardboard boxes.


Question : What are ethylene sensitive cargoes?

A. Ethylene is the sweet smelling gas which is evolved when fruits ripen. It is one of the products of chemical reactions taking place inside a fruit when fruits ripen. Other sources of ethylene are combustion of fuel in automobile engines, fluorescent light ballasts, and some fungi and bacteria. Though the quantity of ethylene generated is small (in ppm), it can affect the fruits to a considerable extent depending upon the type of fruit, and the amount and duration of exposure to the fruit. If not desired, ethylene produced while ripening of the fruit has to be drawn out from the atmosphere by using ethylene scrubbers which contain potassium permanganate which has the property of absorbing ethylene and converting it into harmless and ineffective products.

Depending upon their sensitivity to ethylene, fruits can be classified into climacteric or non-climacteric fruits.


Climacteric fruits are excessively sensitive to ethylene. They form an irreversible reaction which accelerates ripening uncontrollably. Once these fruits are exposed to even a small amount of ethylene, the ripening process cannot be retarded or controlled and they ripen at an accelerating pace. Such fruits must be consumed within a few days, otherwise they will become over-ripe and lose quality. Some fruits like tomatoes, bananas and honeydews are deliberately exposed to ethylene to ensure rapid and uniform cooling. On the other hand, for some fruits like kiwifruit and Bartlett pears, ethylene must be rigorously excluded, otherwise, they will become overripe and unusable.

Examples: apple, apricot, avocado, banana, blueberry, breadfruit, cherimoya, feijoa, fig, guava, jackfruit, kiwifruit, mango, muskmelon, nectarine, papaya, passion fruit, peach, pear, parsimmon, plantain, plum, sapote, soursop, tomato, watermelon etc.

Non-climacteric fruits are those fruits whose ripening process can be accelerated or retarded by exposing them to measured amounts of ethylene. By removing the ethylene at any stage of ripening, the process can be slowed down. The ripening process is not irreversible.

Examples: blackberry, cacao, cashew apple, cherry, cucumber, eggplant, grape, grapefruit, jujube, lemon, lime, loquat, lyches, olive, orange, pepper, pineapple, pomegranate, raspberry, satsuma mandarin, strawberry, summer squash, tamarillo, tangerine etc.

Examples: Some varieties of apples, apricots, avocados, asparagus, cantaloupes, snap beans, cherimoya, cranberry, cucumber, eggplant, flowering potted plants, foliage plants, grapefruit, kiwifruit, lemon, limes, olives, papaya, bell peppers, pineapple, tomatoes etc.

Download here (copy & paste address)
http://www.hamburgsud.com/group/media/sharedmedia/dokumente/brochures/Reefer_guide.pdf

This list is not exhaustive. There are many more products which are not covered in the above list. The shipper's guidelines must be followed for all refrigerated cargoes for the correct storage temperature.