Grain Code and Hazard associated with Grain Cargo

 Grain Code

The International Code for the Safe Carriage of Grain in Bulk is commonly called the “International Grain Code” was adopted by the IMO Maritime Safety Committee by resolution MSC.23(59). It applies to ships regardless of size, including those of less than 500grt, engaged in the carriage of grain in bulk. 

Effective 1 January 1994 

What is Grain Cargo ? 

Grains includes wheat, rye, maize, rice, oats, barley , pulses, seeds  and their processed forms whose behaviour is similar to that of grain in its natural state

The carriage of grain is associated with two main hazards 

1.  Settling and 

2. Shifting

There are other minor hazards associated with grain such as contamination, dust explosion, fire, rotting due to ingress of water and consequent depletion of oxygen or evolution of toxic vapours.

Hazard of shifting

A compartment may be full when the cargo is loaded but, due to ship's vibration and other movements, the grain settles by about 2 % of its volume leaving space at the top of the cargo. This space allows cargo to move from side to side in conjunction with the rolling and pitching of the vessel. 

As the cargo shifts the vessel lists to one side. The shifting of grain is the greatest hazard involved in the carriage of grain. 

Grain has a low angle of repose (15 – 18 deg  depending on the type of grain) and this results in its shifting very easily. 

Thus the heeling moments for the ship are to be kept as small as possible

This is done by

1. Having maximum number of holds Completely filled with grain

2. Restraining  or securing the grain surface to prevent  shifting