As mentioned in a previous post, grain transportation by sea is subject to distinct regulations.

The International Grain Code, which was adopted by resolution MSC.23(59) and came into force on January 1, 1994, is mandatory under SOLAS chapter VI. The code applies to all types of vessels, including those under 500 gross tonnage, that transport grain in bulk and are subject to part C of SOLAS chapter VI.

The term “grain” refers to wheat, maize (corn), oats, rye, barley, rice, pulses, seeds, and their processed forms whose behavior is similar to that of natural grain.

The International Grain Code aims to provide a global standard for the safe carriage of grain in bulk.

In general, several precautions must be taken to ensure safe grain loading onto a vessel. The following are the most important ones:

Before loading:

• the shipper must provide information about the cargo, 
• stability criteria must be calculated 
• all planning, of loading should be carried out with stability in mind,
• cargo holds should be cleaned and checked for bilge water and hatch weather tightness. 
• an initial draft survey should be conducted before loading.

During loading:

• the hull stresses should be continuously monitored,
• the cargo should be trimmed as per the loading plan. 
• the cargo should be checked for damage, 
• moorings should be inspected frequently.

Before vessel’s departure: 

• the cargo must be secured to minimize heeling moments. 
• all cargo holds should be closed and appropriately secured to prevent seawater from entering in adverse weather conditions.
• the final state of stability should be calculated after loading completion.

To avoid cargo shifting, the grain surfaces must be reasonably trimmed. Most grains have an angle of repose (slip angle) of approximately 20° from the horizontal. If the ship rolls more than 20°, the cargo will shift, causing the ship to list (taking on water and tilting to one side) and roll further, which may lead to the vessel’s capsizing. 

To prevent this from happening, the cargo should be trimmed as follows:

• Filled compartment – all spaces under the deck and hatch covers are to be filled to the maximum extent possible.
• If the cargo is stowed only in the lower compartment, the lower compartment hatch covers should be secured as per the approved manner.
• In partly filled compartments, the bulk grain surface should be secured by over-stowing, except when heeling moments due to grain shift have been calculated and considered for the vessel’s stability.
• Longitudinal divisions can be installed to reduce heeling moments caused by the shift of grain in filled, trimmed compartments, untrimmed, and partly filled compartments.