Deck Cargo: Code of Safe Practice for Ships Carrying Timber Deck Cargoes

Timber refers to sawn wood or lumber, cants, logs, poles, pulpwood, or any other types of timber in loose or packaged forms.

Timber Deck Cargo: Refers to the cargo of timber carried on an uncovered part of the freeboard deck.

Timber Loadline: Refers to a special load line assigned to ships that comply with certain regulations of the International Load Line Convention (ILC) regarding ship construction, stowage, and securing of cargo.

Stability Information: The stability of a ship should always be positive. Factors to consider for stability include:

1. Increase in weight of timber due to water absorption or ice accretion.

2. Reduction of bottom weight due to the consumption of fresh water and fuel.

3. Free surface effect of liquid in slack tanks.

4. Ingress of water in broken spaces, adding extra weight to the timber cargo.

Stability criteria vary based on different loading scenarios:

  • Fully Loaded Departure: Cargo hold full, deck empty, store full.
  • Fully Loaded Arrival: Hold full, deck empty, store 10%.
  • Ballast Departure: Store full.
  • Ballast Arrival: Store 10%.
  • Fully Loaded Departure: Hold + deck full, store full.
  • Fully Loaded Arrival: Hold + deck full, store 10%.

Tables or diagrams displaying stability and initial GM (metacentric height) at various drafts should be provided to ensure compliance with stability criteria. Rolling period tables/diagrams are also necessary for initial GM (FSE correction).

Max. Permissible Deck Cargo: Information about the maximum allowable deck cargo should be provided.

Anti-Rolling Devices: If the ship is equipped with anti-rolling devices, details about them should be provided.

The master should halt loading operations if the ship develops an unknown list. The ship must be upright and comply with stability criteria before proceeding to sea. It is recommended that GM (metacentric height) does not exceed 3% of the ship’s beam to avoid rapid and violent motion in heavy seas.

To ensure the safety of timber deck cargo, it is important to:

1. Stow the cargo solidly and compactly to induce reserve buoyancy.

2. Prevent slack that could loosen lashings.

3. Create a binding effect with the stow to prevent loosening of adjacent cargo.

4. Reduce permeability of the stow to minimize water and ice ingress.

Lashing:

Appropriate lashing should be used to prevent shifting of deck cargo. The lashing should have sufficient strength as recommended by the code.

Shifting of Cargo:

Cargo shifting can occur due to various reasons, including insufficient strength of lashings, movement of cargo across the deck, failure of uprights (lacking strength or excessive force), and heavy rolling or pitching caused by rough seas.

Preparation before Loading:

– Hatch covers and openings must be securely closed and battened.

– Airpipes, sounding pipes, and ventilators should be protected.

– Ice and snow should be removed from the deck.

– Lashing gear should be checked and kept ready (rigged) before loading.

Precautions during Loading:

– Constant supervision is necessary to ensure a compact stow.

– The ship must be loaded upright without any unsymmetrical loading.

– Safe access to crew quarters, pilot boarding area, machinery spaces, and all other working spaces should be maintained.

– Working spaces should be securely closed.

– Before departing, a thorough inspection and sounding of all tanks should be conducted.

Height of Deck Cargo:

Considerations for the height of deck cargo include:

– Adequate visibility for navigation and lookout duties.

– A safe margin of stability.

– Lowering the height

Leave a Reply

Your email address will not be published. Required fields are marked *