Before packing dangerous goods into container the interior and exterior of the container must be thoroughly examined. Every package of dangerous goods, drums, jerricans, boxes, bags etc. must be visually inspected for any damage. Packages leaking or damaged must not be loaded into the container. Packer must check whether the packages are marked, labelled and are having UN Performance marking on them.
Rules for securing cargo inside container is same for dangerous goods and non-dangerous goods. Improperly secured goods are prone to damage due to movement inside when exposed to acceleration. Rolling and pitching of vessel and hard braking of vehicles may cause goods to move inside the container, stacks collapsing, heavy goods to even break through the container walls.
When oversized machinery or vehicles are secured on container the dangerous goods in the machinery or vehicle must not leak or spill.
Whenever possible liquid dangerous goods must be loaded below dry dangerous goods. Similarly, while loading dangerous and non-dangerous into same container dangerous goods should be kept towards the door end when possible. The marks and labels of dangerous goods packages should face the door end.
Packages with vents, drums, and those having orientation marks must always be kept upright. IMDG Code prohibits drums on roll. If the packages are not designed for stacking the tiers must be separated with dunnage. Some shipping lines have a policy to get a letter signed by shipper stating dunnage is used while shipping liquid dangerous goods in plastic drums. This is to ensure the top tier wont crush the bottom tier and cause leakage.
Goods must be properly blocked, braced or secured or empty space between goods filled with dunnage bags or air bags. While using air bags to fill the space one must take into consideration the force on the bag from cargo. If the pressure of the air bag is low then there is possibility of bag becoming loose and if the pressure is too high there is possibility of bag breaking due to temperature variance.
When different dangerous goods are to be loaded into the container segregation rules of IMDG Code shall be met with. When combined road, rail and sea transport is involved the most stringent provisions of IMDG Code is applicable for segregation.
Steps for checking segregation according to 37th amendment of IMDG Code
- Read the general segregation provisions (chapter to 7.2)
- Identify the UN No., Proper Shipping Name, class or division, subsidiary hazard class or division, if any, and where assigned packing group for each substance
- Are the dangerous goods exempted from the general segregation provisions example; Limited Quantities, Excepted Quantities, Special Provisions of segregation, Acids and Alkalis in class 8? If yes, follow same
- If no, check segregation requirement of column 16b in dangerous goods and any segregation applicable as per dangerous goods declaration
- a) If no segregation applicable as per above, use segregation table in accordance with general segregation provisions
- b) If segregation is applicable according to above, Use the segregation table taking into account any specific or general segregation provisions and determine the specific segregation provisions for each substance (e.g., segregation groups), Ensure the most stringent requirements are taken.
Responsibility of packer: Those who pack a dangerous goods container is responsible to issue a Container Packing Certificate, CPC is not required for tanks. The declaration of this certificate must read “I hereby declare that the goods described above have been packed/ loaded into the container/vehicle identified above in accordance with the applicable provisions” and must be signed. This certifies that;
- The container/vehicle was clean, dry and apparently fit to receive the goods.
- If the consignments include goods of class 1, other than division 1.4, the container is structurally serviceable.
- No incompatible goods have been packed into the container/vehicle unless specially authorised by the Competent Authority.
- All packages have been externally inspected for damage and only sound packages packed.
- Drums have been stowed in an upright position, unless otherwise authorised by the Competent Authority.
- All packages have been properly packed and secured in the container/vehicle.
- When materials are transported in bulk packagings the cargo has been evenly distributed in the container/vehicle.
- The packages and the container/vehicle have been properly marked, labelled and placarded. Any irrelevant mark, labels and placards have been removed.
- When solid carbon dioxide (CO2 – dry ice) is used for cooling purposes, the vehicle or freight container is externally marked or labelled in a conspicuous place, e.g. at the door end, with the words: DANGEROUS CO2 GAS (DRY ICE) INSIDE – VENTILATE THOROUGHLY BEFORE ENTERING.
A poorly packed container exposes transport workers and ship staff to risk additionally they pose risk to other cargo, equipment and environment.
For guidance refer Code of Practice for Packing of Cargo Transport Units published by IMO, ILO and UNECE. Searchable version of same can be found at https://www2.unece.org/wiki/display/TransportSustainableCTUCode/CTU+Code