2. Construction and Structural Strength

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2.1 Hulls

2.1.1 All ships should be of adequate structural strength to withstand the sea and weather conditions likely to be encountered in the intended area of operation.

2.1.2 Hull, scantlings, decks and superstructures of a new ship may be constructed of any material acceptable to Transport Canada Inspectors.

2.1.3 An existing ship will be considered to be of adequate structural strength if it is in a good state of repair and is:

  1. built to the standards prescribed by classification societies acceptable to Transport Canada ( TC ); or
  2. of a design with a record of at least 5 years safe operation in an area where the sea and weather conditions are no less severe than those likely to be encountered in the intended area of operation.

2.1.4 In constructing metal hulls, due consideration should be given to electrolytic corrosion, and appropriate means of minimizing its effects should be employed. In applying corrosion protection measures, the ship should be deemed to be intended for operation in seawater except if it is to be limited to freshwater operation. In ships with metal hulls, an isolation transformer or a galvanic isolator in the grounding conductor of shore power connection may be considered to reduce galvanic corrosion.

2.2 Weather Deck

2.2.1 The ship should have a weathertight weather deck which extends from stem to stern. The weather deck may be stepped, recessed or raised provided the stepped, recessed or raised portion is of weathertight construction.

2.2.2 Any recess in weather deck should be self-draining under normal conditions of heel and trim and the means of drainage should be capable of efficient operation when the ship is heeled to 30 degrees.

2.3 Watertight Bulkheads and Subdivision

2.3.1 Each ship should be fitted with collision bulkhead and machinery space bulkheads. For ships having small machinery spaces, those spaces may be protected with partial transverse and longitudinal bulkheads forming an enclosure in lieu of the full transverse bulkheads.

2.3.2 The collision bulkhead should be located at a distance of not less than 5% and not more than 10% of the LWL abaft the stem measured at the deepest operational waterline. For ships with a higher rake of stem, the collision bulkhead may be stepped, with the lower part of the bulkhead to step located as above, and the top of the step being not less than 2.5% of LWL above the deepest operational waterline.

2.3.3 Every new ship should be subdivided with watertight bulkheads so arranged that the flooding of any one compartment will not cause the ship to float at waterline which is less than 75 mm below the weather deck at any point. Subdivision analysis should be based on the assumption that the ship is in the maximum loaded condition and be carried out using standard permeabilities as defined in the Hull Construction Regulations.

2.3.4 It is recommended that ships for which 2.3.3 applies, have the residual stability in the final flooded condition after damage such that:

  1. the angle of equilibrium does not exceed 7 degrees from upright;
  2. the resulting righting lever curve has a range of at least 15 degrees beyond the angle of equilibrium; and
  3. the maximum righting lever within the range that is not less than 0.015 metre radians;

2.3.5 It is also recommended that at intermediate stages of flooding the maximum righting lever be at least 50 mm with a range of positive righting levels of at least 7 degrees.

2.3.6 Existing ships having a length of 24 m and above should comply with the provisions given in the section 2.3.3. Ships which do not meet these requirements may be accepted by Marine Safety after an assessment of the deficiencies is made and consideration is given to compensatory measures such as operational limitations.

2.3.7 For existing ships of less than 24 m in length, it is strongly recommended that modifications which would cause the ship to comply with provisions given in the section 2.3.3 be implemented when the ship undergoes major structural alterations.

2.3.8 The provisions given in sections 2.3.3 do not need to apply to ships operating exclusively on minor water voyages as defined in the Home Trade, Inland and Minor Waters Voyages Regulations.

2.3.9 Where pipes, cables etc. penetrate watertight bulkheads they should be fitted with valves and watertight glands as appropriate.

2.3.10 Doorways fitted in watertight bulkheads should be of watertight construction and unless otherwise authorised by the Master, be kept closed while at sea.

2.4 Masts, Spars and Rigging

2.4.1 The design, materials and construction of masts, yards, booms, bowsprits and standing rigging including their supporting structures should be suitable for intended service and should have adequate strength to withstand the highest loadings imposed by the sail system during all normal and emergency operations.

2.4.2 Particular attention should be given to the integration of the masts and rigging into the hull structure. The hull structure should be adequately reinforced and stiffened to ensure sufficient strength and resistance to plate buckling.

2.4.3 All standing rigging should have positively secured ends, and lower terminations should incorporate means of adjustment. Safe, traditional, time proven methods may be acceptable if considered satisfactory to the attending inspector.

2.4.4 All running rigging should be provided with clear running leads, using swivel blocks, fairleads, pad-eyes, etc. as appropriate. All running rigging components should be of adequate design and size to minimize the risk of jamming.

2.4.5 The strength of all blocks, shackles, rigging screws, cleats and associated fittings and attachment points should exceed the breaking strength of associated running and standing rigging.

2.4.6 Every ship should be provided with adequate means of reefing or shortening sails.

2.4.7 Unless clearly unsuitable, every ship should either be provided with separate storm sails of adequate strength and size or have specific sails designated and constructed to act as storm canvas.

2.4.8 Adequate provision should be made for securing running rigging, assuming the simultaneous use of sails.

2.5 Fabrication Standards

2.5.1 Hull construction and maintenance should be carried out in an appropriate environment as prescribed by the manufacturer.

2.5.2 Hulls should be fabricated in facilities equipped as appropriate for the material of construction; materials of construction and any consumables used during fabrication should be stored in such a way as to prevent corrosion or other deterioration, and in compliance with any instructions provided by the manufacturer.

2.5.3 Wooden fabrication of hulls should, to the most complete stage practical, be performed in well ventilated covered premises.

2.5.4 Fibre reinforced plastic fabrication should be carried out in a an environment with atmospheric control to maintain the temperature between 15° and 21 °C ., and relative humidity constant within the range 40%-80% during fabrication.

2.5.5 Welded fabrication should be performed by welders holding appropriate certification in compliance with standards and practices appropriate to the material of construction, welding methods and equipment being used. This provision is not intended to exclude work carried out by a recognised apprentice welder or metal worker under the supervision of a tradesman welder.

2.5.6 All construction other than welding should be performed by persons skilled in the particular method and material of construction.

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