Chapter 4

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Securing

4.1 General

4.1.1 Every lashing should pass over the timber deck cargo and be shackled to eye plates and adequate for the intended purpose and efficiently attached to the deck stringer plate or other strengthened points. They should be installed in such a manner as to be, as far as practicable, in contact with the timber deck cargo throughout its full height.

4.1.2 All lashings and components used for securing should:

1. possess a breaking strength of not less than 133 kN;
2. after initial stressing, show an elongation of not more than 5% at 80% of their breaking strength; and
3. show no permanent deformation after having been subjected to a proof load of not less than 40% of their original breaking strength.

4.1.3 Every lashing should be provided with a tightening device or system so placed that it can safely and efficiently operate when required. The load to be produced by the tightening device or system should not be less than:

1. 27 kN in the horizontal part; and
2. 16 kN in the vertical part.

NOTE: 1 Newton equals 0.225 lbs. force or 0.1 kgf.

4.1.4 Upon completion and after the initial securing, the tightening device or system should be left with not less than half the threaded length of screw or of tightening capacity available for future use.

4.1.5 Every lashing should be provided with a device or an installation to permit the length of the lashing to be adjusted.

4.1.6 The spacing of the lashings should be such that the two lashings at each end of each length of continuous deck stow are positioned as close as practicable to the extreme end of the timber deck cargo.

4.1.7 If wire rope clips are used to make a joint in a wire lashing, the following conditions should be observed to avoid a significant reduction in strength:

1. the number and size of rope clips utilized should be in proportion to the diameter of the wire rope and should not be less than four, each spaced at intervals of not less than 15 cm;
2. the saddle portion of the clip should be applied to the live load segment and the U-bolt to the dead or shortened end segment;
3. rope clips should be initially tightened so that they visibly penetrate into the wire rope and subsequently be retightened after the lashing has been stressed.

4.1.8 Greasing the threads of grips, clips, shackles and turnbuckles increases their holding capacity and prevents corrosion.

4.1.9 Canadian modification - lashings with releasing arrangements may optionally be fitted.

4.2 Uprights

4.2.1 Uprights should be fitted when required by the nature, height or character of the timber deck cargo.

4.2.2 When uprights are fitted, they should:

1. be made of steel or other suitable material of adequate strength, taking into account the breadth of the deck cargo;
2. be spaced at intervals not exceeding 3 m;
3. be fixed to the deck by angles, metal sockets or equally sufficient means; and
4. if deemed necessary, be further secured by a metal bracket to a strengthened point, i.e., bulwark, hatch coaming.

4.2.3 Canadian modification - uprights shall be fitted when:

1. the maximum height of the cargo above the weather deck exceeds 2.44 metres; or
2. the maximum height of the cargo above the hatch cover exceeds 2.44 metres or more than two bundles; and
3. the ship is loading in a port located within the seasonal winter load line zone within the period during which the winter load line is applicable;
   
   or in any other case where considered necessary.

4.3 Loose or Packaged Sawn Timber

4.3.1 The timber deck cargo should be secured throughout its length by independent lashings.

4.3.2 Subject to subsection 4.3.3 the maximum spacing of the lashings referred to above should be determined by the maximum height of the timber deck cargo in the vicinity of the lashings:

1. for a height of 4 m and below, the spacing should be 3 m;
2. for heights of above 4 m, the spacing should be 1.5 m.

4.3.3 The packages stowed at the upper outboard edge of the stow should be secured by at least two lashings each.

4.3.4 When the outboard stow of the timber deck cargo is in lengths of less than 3.6 m, the spacing of the lashings should be reduced as necessary or other suitable provisions made to suit the length of timber.

4.3.5 Rounded angle pieces of suitable material and design should be used along the upper outboard edge of the stow to bear the stress and permit free reeving of the lashings.

4.4 Logs, Poles, Cants or Similar Cargo

4.4.1 The timber deck cargo should be secured throughout its length by independent lashings spaced not more than 3 m apart.

4.4.2 If the timber deck cargo is stowed over the hatches and higher, it should, in addition to being secured by the lashings recommended in 4.4.1, be further secured by:

1. a system of athwarthship lashings (hog lashings) joining each port and starboard pair of uprights near the top of the stow and at other appropriate levels as appropriate for the height of the stow; and
2. a lashing system to tighten the stow whereby a dual continuous wire rope (wiggle wire) is passed from side to side over the cargo and held continuously through a series of snatch blocks or other suitable device, held in place by foot wires.

4.4.3 The dual continuous wire rope, referred to in 4.4.2.2. should be led to a winch or other tensioning device to facilitate further tightening.

4.4.4 The recommendation of 4.3.5 should apply to a timber deck cargo of cants.

4.5 Testing, Examination and Certification

4.5.1 All lashings and components used for the securing of the timber deck cargo should be tested, marked and certified according to national regulations or an appropriate standard of an internationally recognized standards institute. Copies of the appropriate certificate should be kept on board.

4.5.2 No treatments which could hide defects or reduce mechanical properties or strength should be applied after testing.

4.5.3 A visual examination of lashings and components should be made at intervals not exceeding 12 months.

4.5.4 A visual examination of all securing points on the ship, including those on the uprights, if fitted, should be performed before loading the timber deck cargo. Any damage should be satisfactorily repaired.

4.5.5 Canadian modification - all lashings and components used for the stowage of timber cargo shall be tested and certified at least once every four years in accordance with Appendix E.

4.6 Lashing Plans

One or more lashing plans complying with the recommendations of this Code should be provided and maintained on board a ship carrying timber deck cargo.

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