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General Load Line Rules (CRC Vol. XVI c. 1425) - Canada Shipping Regulations. (ID: 9540)
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Publications Vehicle importation Vehicle recalls Transport Canada CANADA SHIPPING ACT General Load Line Rules CRC, Vol. XVI, c. 1425 -------------------------------------------------------------------------------- Short Title Interpretation Application General Conditions of Assignment Assignment of Freeboards Load Line Marks Application for a Certificate General Provisions Respecting Certificates Verification of Load Line Marks Surveys and Inspections Inspectors' Reports and Records Powers of Port Wardens Limits of Submergence SCHEDULE I SCHEDULE II SCHEDULE III SCHEDULE IV Established by -------------------------------------------------------------------------------- CANADA SHIPPING ACT General Load Line Rules GENERAL RULES RESPECTING LOAD LINES FOR SHIPS Short Title 1. These Rules may be cited as the General Load Line Rules. Interpretation 2. In these Rules, "Act" Loi "Act" means the Canada Shipping Act; "certificate" certificat "certificate" means a certificate issued pursuant to section 420 or 426 of the Act; "freeboard" franc-bord "freeboard" means a distance that is calculated in respect of a ship in accordance with these Rules and measured vertically downward from a position coinciding with the mid-point of the upper edge of the deck line; "inspector" inspecteur "inspector" means a steamship inspector appointed pursuant to section 366 of the Act; "North American Great Lakes Zone" zone des Grand lacs de l'Am rique du Nord "North American Great Lakes Zone" means Lake Ontario, Lake Erie, Lake Huron (including Georgian Bay), Lake Michigan, Lake Superior, the waters connecting those lakes, the St. Lawrence Seaway and the St. Lawrence River west of the Victoria Bridge in Montreal; "St. Lawrence River Seasonal Area" r gion p riodique du fleuve Saint-Laurent "St. Lawrence River Seasonal Area" means that part of the St. Lawrence River bounded by the Victoria Bridge in Montreal, a straight line drawn from Cap des Rosiers to West Point, Anticosti Island, and a line drawn along the meridian of longitude 63 degrees west from Anticosti Island to the north shore of the St. Lawrence River; "sailing ship" voilier "sailing ship" includes every ship provided with sufficient sail area for navigation under sails alone, whether or not fitted with mechanical means of propulsion; "steamship" navire vapeur "steamship" includes (a) every ship that has sufficient mechanical means for propulsion, and does not have sufficient sail area for navigation under sails alone, and (b) every lighter, barge or other ship that is towed and does not have independent means of propulsion; "tanker" navire-citerne "tanker" includes a steamship specially constructed for the carriage of liquid cargoes in bulk; "timber deck cargo" chargement de bois en pont e "timber deck cargo" means a cargo of timber carried on an uncovered part of a freeboard deck or superstructure deck, as defined in Schedule I, but does not include a cargo of wood pulp or similar cargo; "1930 Convention" Convention de 1930 "1930 Convention" means the International Load Line Convention, 1930; "1966 Convention" Convention de 1966 "1966 Convention" means the International Convention on Load Lines, 1966. Application 3. (1) Subject to subsection (2), these Rules apply to every ship of 150 tons, gross tonnage or more, carrying passengers or cargo that is (a) a Canadian ship, or (b) a ship that is not a Canadian ship making a voyage from a place in Canada to another place in Canada or from a place in Canada to a place not in Canada, and the keel of which was laid or construction of the hull of which was commenced before (c) the date on which the 1966 Convention came into force in a country that is a party to that Convention, in the case of a ship that is not a Canadian ship and that is flying the flag of that country; (d) April 14, 1970, in the case of a Canadian ship that makes more than an occasional international voyage; or (e) April 14, 1973, in the case of a Canadian ship that does not make international voyages or that makes only an occasional international voyage, and in the case of a ship that is not a Canadian ship that is flying the flag of a country that is not a party to the 1966 Convention. (2) These Rules do not apply to (a) a ship of war, a fishing vessel or a pleasure yacht; (b) a ship in respect of which a request is made, by or on behalf of an owner, for the application to that ship of the Load Line Regulations (Sea); (c) a ship that is marked with the load line marks and assigned freeboards in accordance with the Load Line Rules for Lakes and Rivers, the Load Line Regulations (Inland) or similar load line regulations made under the laws of the United States, and that is making a voyage solely within the limits of the inland waters of Canada or is making an inland voyage; (d) a ship making (i) a home-trade voyage, Class IV, (ii) a voyage on the sea coasts of Canada that, in the opinion of the Board, is comparable to a home-trade voyage Class IV, or (iii) a minor waters voyage, Class II; (e) a ship without means of self-propulsion that is making a voyage from a place in Canada to another place in Canada and that does not carry passengers or crew; (f) a Canadian ship or a United States ship making an international voyage wholly within (i) the waters of Puget Sound in the State of Washington, (ii) the waters lying between Vancouver Island and the mainland and east of a line drawn from a point 1 nautical mile west of the city limits of Port Angeles in the State of Washington to Race Rocks on Vancouver Island, and east of a line drawn from Hope Island, British Columbia, to Cape Calvert, Calvert Island, British Columbia, (iii) the waters lying east of a line drawn from Cape Calvert to Duke Point on Duke Island in the State of Alaska, (iv) the waters lying north of Duke Island and east of Prince of Wales Island, Baranof Island and Chicagof Island, all in the State of Alaska, (v) the waters of Peril, Neva and Olga Straits as far south as Sitka in the Strait of Alaska, and (vi) the waters lying east of a line drawn from Port Althorp on Chicagof Island to Cape Spencer, in the State of Alaska; or (g) a ship that, at the time of its departure on a voyage, was not subject to the provisions of any regulations made to give effect to the 1930 or 1966 Convention during the course of its intended voyage and that is at a place in Canada due to stress of weather or any other cause of force majeure. General 4. Notwithstanding anything in these Rules, a freeboard may be assigned to a ship that is greater than the minimum freeboard for the ship as determined by these Rules. Conditions of Assignment 5. The conditions of assignment for the purposes of Part VIII of the Act are set out in Part I of Schedule I. Assignment of Freeboards 6. Subject to sections 10 and 10.1, a steamship other than a sailing ship or a tanker shall be assigned freeboards in accordance with Part II of Schedule I. 7. A sailing ship shall be assigned freeboards in accordance with Part III of Schedule I. 8. A steamship carrying a timber deck cargo shall be assigned freeboards in accordance with Part IV of Schedule I in addition to the freeboards assigned pursuant to section 6. 9. A tanker shall be assigned freeboards in accordance with Part V of Schedule I. 10. (1) A steamship of a special type over 91.4 m in length and possessing constructional features similar to those of a tanker that, in the opinion of the Board, afford extra invulnerability against the sea may be granted by the Board a lesser freeboard than that assigned pursuant to section 6. (2) A freeboard assigned pursuant to subsection (1) shall be determined by the Board with reference to the freeboards assigned pursuant to section 9, having regard to the extent to which the ship complies with the conditions of assignment applicable to a tanker and the degree of subdivision provided in the ship, but the freeboard assigned to the ship shall in no case be less than the freeboard that would be assigned to it if it were a tanker. 10.1 The Board may assign to any dredger, sandsucker, open hopper barge or other ship of special design a freeboard that is less than the freeboard calculated in accordance with Part II of Schedule I, or partly or wholly exempt such a ship from the provisions of section 3 of Schedule I, if the ship (a) is engaged in voyages that are not international voyages; (b) meets the requirements for the issue of a Local Load Line Certificate; and (c) is of such design and stability that such lesser freeboard or such exemption, as the case may be, will not adversely affect its safety. Load Line Marks 11. (1) Every ship that is assigned freeboards in accordance with these Rules shall be marked in accordance with Part VI of Schedule I. (2) The position of each load line shall be such that the distance measured vertically from the upper edge of the deck line to the upper edge of the load line shall be equal to the freeboard assigned to that ship that is appropriate to that line. Application for a Certificate 12. Every owner of a ship who applies to the Chairman for the issue or renewal of a certificate shall (a) apply in writing; (b) submit such plans and information as the Chairman may require; and (c) provide facilities that, in the opinion of an inspector, are sufficient for the purpose of surveying the ship. General Provisions Respecting Certificates 13. (1) Every certificate issued pursuant to section 420 of the Act shall (a) in the case of a ship making international voyages, be in the form set out as Form 1 in Schedule II; and (b) in the case of a ship not making international voyages, be in the form set out as Form 2 in Schedule II. (2) Every certificate issued pursuant to section 426 of the Act shall be issued in the form set out as Form 3 in Schedule II. 14. A certified copy shall be made of every certificate and, where any endorsement is made on the certificate, an identical endorsement shall be made thereafter on the certified copy. Verification of Load Line Marks 15. A certificate shall not be delivered to a ship until an inspector has certified in his report that the load line marks are correctly and permanently indicated on the ship's sides. Surveys and Inspections 16. (1) Every survey of a ship that is made before a certificate is issued or renewed shall consist of a complete survey of its structure, equipment, arrangements, materials and scantlings to ensure that the ship complies fully with the conditions of assignment of freeboards for that ship and that the load line marks correspond with the assigned freeboards. (2) Every periodical inspection of a ship that is made after the issue of a certificate in respect of the ship shall consist of an inspection to ensure that (a) no material alterations have taken place in the hull or superstructure of the ship that would affect the positions of the load lines; and (b) the fittings and appliances for the protection of openings, the guard rails, the freeing ports and the means of access to the crew's quarters, and, in the case of a ship assigned timber freeboards, the permanently attached fittings and appliances for securing and stowing the timber deck cargo have been maintained in as effective a condition as they were in when the certificate was issued. (3) Where a periodical inspection is made of a ship and the inspector is satisfied that the ship meets the requirements set out in paragraphs (2)(a) and (b), he shall endorse the certificate to that effect in the space provided therefor. (4) When a survey or inspection referred to in this section is made, the owner of the ship shall pay the appropriate fee set out in the Board of Steamship Inspection Scale of Fees. Inspectors' Reports and Records 17. (1) When a survey referred to in subsection 16(1) is completed, the inspector who made the survey shall forward to the Chairman, (a) a report stating the results of the survey; and (b) a record of all the details of the survey or, in the case of a ship that has been previously surveyed, any amendments to the record. (2) The Chairman shall, upon assigning freeboards to a ship, return a copy of the record to the owner of the ship who shall place it on board the ship in the custody of the master. (3) On completion of a periodical inspection referred to in subsection 16(2), the inspector shall forward to the Chairman a report stating the result of the inspection. Powers of Port Wardens 18. A port warden may go on board any ship to determine whether a certificate is on board the ship and, if a certificate is on board, may (a) take such measurements as are necessary to determine whether the ship is loaded beyond the limit of submergence specified in the certificate; and (b) determine whether the positions of the load line marks correspond to the positions specified for those marks in the certificate. Limits of Submergence 19. (1) Subject to sections 22 and 23, the maximum depth in salt water to which a ship that is not a Canadian ship that is flying the flag of a country that is a party to the 1930 Convention only may be loaded is described in Part VII of Schedule I. (2) Subject to subsection (5) and sections 22 and 23, the maximum depth in salt water to which a ship, other than a ship described in subsection (1), may be loaded is to the upper edge of the load line corresponding to the seasonal period described in Schedule IV in respect of a seasonal zone or a seasonal area described in that Schedule, while the ship is in that zone or area during that period. (3) Where a ship is assigned timber freeboards and is not (a) in the North American Great Lakes Zone, or (b) making a voyage wholly within the limits of the North American Great Lakes Zone and the St. Lawrence River Seasonal Area, any reference in subsections (2) and (5) to a load line shall be deemed to be a reference to a timber load line. (4) A port standing on the boundary line between two zones or areas described in Schedule IV shall be regarded as being within the zone or area from or into which the ship arrives or departs. (5) The maximum depth in salt water to which a ship that has been assigned a winter North Atlantic freeboard, other than a ship described in subsection (1), may be loaded is to the upper edge of the winter North Atlantic load line during (a) the period from October 16th to April 15th, while the ship is in the North Atlantic Winter Seasonal Zone I, as described in Schedule IV; or (b) the period from November 1st in one year to March 31st in the next year, while the ship is in that part of the North Atlantic Winter Seasonal Zone II, as described in Schedule IV, that lies between the meridian of longitude 15 W and 50 W. 20. (1) Subject to section 21, a ship in fresh water of unit density may be loaded so as to submerge to the depth permitted in section 19 plus the amount of the fresh water allowance calculated in accordance with section 57 of Schedule I. (2) Subject to section 21, a ship in water of other than unit density may be loaded so as to submerge to the depth permitted in section 19 plus the allowance calculated in accordance with section 57 of Schedule I made proportional to the difference between 1.025 and the actual density. 21. Section 20 does not apply to a ship that (a) is in the North American Great Lakes Zone at any time during the period from September 16th in any year to April 30th in the next year; or (b) would submerge all assigned load lines were it to submerge the appropriate load line by the amount of the fresh water allowance. 22. (1) Subject to subsection (2), when a ship departs from a place in inland waters, the ship may be loaded so as to submerge to a greater depth than that permitted by section 19 or 20, which greater depth shall correspond to the weight of fuel and all other materials required for consumption between the point of departure and the sea. (2) Subsection (1) does not apply to a ship in (a) the North American Great Lakes Zone; or (b) the St. Lawrence River Seasonal Area where that ship is making a voyage wholly within the limits of that Area and the North American Great Lakes Zone. 23. Where a load line referred to in Part VII of Schedule I or in Schedule II is not marked on the sides of the ship, the point on each side of the ship coinciding with the lower limit of the freeboard that is assigned or should have been assigned to that ship and that corresponds to that load line is the maximum depth in salt water to which a steamship may be loaded while in the zone or area that corresponds to that load line during the season corresponding to that load line. SCHEDULE I (ss. 2, 5, 6, 7, 8, 9, 11, 19, 20 and 23) FREEBOARDS AND MARKING Interpretation 1. (1) In this Schedule, "amidships" milieu du navire "amidships" means the middle of the length of the summer load waterline as defined in subsection (2); "Assigning Authority" autorit habilit e "Assigning Authority" means the Chairman or a classification society authorized pursuant to section 421 of the Act; "flush deck ship" navire au pont ras "flush deck ship" means a ship with no superstructure on the freeboard deck; "freeboard deck" pont de franc-bord "freeboard deck" means the uppermost complete deck having permanent means of closing all openings in weather portions of the deck in accordance with sections 3 to 10, and in flush deck ships and ships with detached superstructures means the upper deck; in ships having discontinuous freeboard decks within superstructures that are not intact, or that are not fitted with Class 1 closing appliances as defined in subsection (12), the lowest line of the deck below the superstructure deck shall be deemed to be the freeboard deck; "superstructure" superstructure "superstructure" means a decked structure on the freeboard deck extending from side to side of the ship, and includes a raised quarter deck and a bridge of set in construction complying with the provisions of subsection (32); "superstructure deck" pont de superstructure "superstructure deck" means the deck forming the top of the superstructure; "surveyor" visiteur "surveyor" means an inspector or a person authorized by an Assigning Authority to conduct surveys. (2) The length (L) for the purposes of this Schedule is the length in metres on the summer load waterline from the foreside of the stem to the afterside of the rudder post; where there is no rudder post, the length is measured from the foreside of the stem to the axis of the rudder stock; for ships with cruiser sterns, the length shall be taken as 96 per cent of the total length on the designed summer load waterline or as the length from the foreside of the stem to the axis of the rudder stock if that be the greater. (3) The breadth (B) for the purposes of this Schedule is the maximum breadth in metres amidships to the moulded line of the frame in iron or steel ships, and to the outside of the planking in wood or composite ships. (4) The moulded depth is the vertical distance in metres measured amidships, from the top of the keel to the top of the freeboard deck beam at side; in wood and composite ships the distance is measured from the lower edge of the keel rabbet; where the form at the lower part of the midship section is of a hollow character, or where thick garboards are fitted, the depth is measured from the point where the line of the flat of the bottom continued inwards cuts the side of the keel. (5) The depth (D) for the purposes of this Schedule is (a) the moulded depth plus the thickness of stringer plate, or plus T(L-S) L if that be greater, where T is the mean thickness of the exposed deck clear of deck openings, and S is the total length of superstructures as defined in subsection (9); (b) where the topsides are of unusual form, the depth of a midship section having vertical topsides, standard round of beam and area of topside section equal to that in the actual midship section and, where there is a step or break in the topsides (e.g., as in the turret deck ship) 70 per cent of the area above the step or break is included in the area used to determine the equivalent; and (c) in a ship without an enclosed superstructure covering at least 0.6L amidships, without a complete trunk or without a combination of intact partial superstructures and trunk extending all fore and aft, where D is less than L 15 the depth used with the table set out in section 58 of this Schedule shall not be taken as less than L 15 (6) The coefficient of fineness (c) for the purposes of this Schedule is obtained by the formula: where D is the ship's moulded displacement (excluding bossing) in salt water in tonnes at a mean moulded draught d., which is 85 per cent of the moulded depth, and where the coefficient (c) is not taken as less than 0.68. (7) The height of a superstructure is the least vertical height measured from the top of the superstructure deck to the top of the freeboard deck beams minus the difference between the moulded depth and D as defined in subsections (4) and (5). (8) The standard height of a raised quarter deck is 0.91 m for ships up to and including 30.5 m in length, 1.22 m for ships 76.2 m in length and 1.83 m for ships 121.9 m in length and above; the standard height of any other superstructure or of a trunk is 1.83 m for ships up to and including 76.2 m in length and 2.29 m for ships 121.9 m in length and above; the standard height at intermediate lengths is obtained by interpolation. (9) The length of a superstructure (S) is the mean covered length of the parts of the superstructure that extend to the sides of the ship and lie within lines drawn perpendicular to the extremities of the summer load waterline, as defined in subsection (2). (10) A detached superstructure is regarded as enclosed only where (a) the enclosing bulkheads are of efficient construction as required by subsection (11); (b) the access openings in these bulkheads are fitted with Class 1 or Class 2 closing appliances (as defined in subsections (12) and (13)); (c) all other openings in sides or ends of the superstructure are fitted with efficient weathertight means of closing; and (d) independent means of access to crew, machinery, bunker and other working spaces within bridges and poops are at all times available when the bulkhead openings are closed. (11) Bulkheads at exposed ends of poops, bridges and forecastles are deemed to be of efficient construction where the Assigning Authority is satisfied that, in the circumstances, they are equivalent to the following standard for ships with minimum freeboards: the stiffeners and plating are of the scantlings given in the table to this section, the stiffeners are spaced 760 mm apart, the stiffeners on poop and bridge front bulkheads have efficient end connections, and those on after bulkheads of bridges and forecastles extend for the whole distance between the margin angles of the bulkheads. TABLE Exposed Bulkheads of Superstructures of Standard Height Bridge front bulkheads Unprotected bulkheads of poops 0.4L or more in length Bulkheads of or protected than 0.4L Poops partially less in length After Bulkheads of Bridges and Forecastles Length of ship Bulb angle stiffeners Length of ship Plain angle stiffeners Length of ship Plain angle stiffeners metres millimetres metres millimetres metres millimetres under 48.8 140 x 75 x 7.5 under 45.7 75 x 65 x 7.5 under 45.7 65 x 65 x 6.5 48.8 150 x 75 x 8 45.7 90 x 65 x 8 45.7 75 x 65 x 7 61 165 x 75 x 8.5 61.0 100 x 75 x 8.5 76.2 90 x 75 x 7.5 73.2 180 x 75 x 9 76.2 115 x 75 x 9 106.7 100 x 75 x 8 85.3 190 x 75 x 9.5 91.4 130 x 75 x 9.5 97.5 205 x 75 x 10 106.7 140 x 75 x 10.5 109.5 215 x 75 x 10.5 121.9 150 x 75 x 11 121.9 230 x 75 x 11 137.2 165 x 90 x 11.5 134.1 240 x 90 x 11.5 152.4 180 x 90 x 12 146.3 255 x 90 x 12 167.6 180 x 90 x 12.5 158.5 265 x 90 x 12.5 170.7 280 x 90 x 13 Length of ship Bulkhead plating Length of ship Bulkhead plating Length of ship Bulkhead plating metres millimetres metres millimetres metres millimetres 61 and under 115.8 and above 7.5 11 48.8 and under 121.9 and above 6 9.5 48.8 and under 121.9 and above 5 7.5 For ships intermediate in length the thickness of bulkhead plating are obtained by interpolation. (12) The following conditions apply to Class 1 closing appliances: they shall be constructed of iron or steel, they shall in all cases be permanently and strongly attached to the bulkhead, they shall be framed, stiffened and fitted so that the whole structure is of equivalent strength to the unpierced bulkhead, and they shall be weathertight when closed; the means for securing these appliances shall be permanently attached to the bulkhead or to the appliances and the latter shall be so arranged that they can be closed and secured from both sides of the bulkhead or from the deck above; the sills of the access openings shall be at least 380 mm above the deck. (13) The following closing appliances shall be Class 2 closing appliances: (a) strongly framed hardwood hinged doors that are not more than 760 mm wide or less than 50 mm thick; (b) shifting boards fitted for the full height of the opening in channels riveted to the bulkheads, the shifting boards being at least 50 mm thick where the width of opening is 760 mm or less, and increased in thickness at the rate of 25 mm for each additional 380 mm of width; or (c) portable plates of equal efficiency with the appliances specified in paragraph (a) or (b). (14) Temporary closing appliances for middle line openings in the deck of an enclosed superstructure shall be regarded as efficient if they consist of (a) a steel coaming not less than 230 mm in height efficiently riveted to the deck; (b) hatchway covers as required by section 5 and secured by hemp lashings; and (c) hatchway supports as required by sections 6 and 7. (15) For the purpose of determining the effective length of detached superstructures subsections (16) to (32) shall apply. (16) Where exposed bulkheads at the ends of poops, bridges and forecastles are not of efficient construction (see subsection (11)) they shall be treated as non-existent. (17) Where in the side plating of a superstructure there is an opening not provided with permanent means of closing, the part of the superstructure in way of the opening shall be regarded as having no effective length. (18) Where the height of a superstructure is less than the standard, its length shall be reduced in the ratio of the actual to the standard height; where the height exceeds the standard, no increase shall be made in the length of the superstructure. (19) Where, at the end of a poop, there is an efficient bulkhead and the access openings are fitted with Class 1 closing appliances, the length of the poop to the bulkhead shall be the effective length. (20) Where the access openings in an efficient bulkhead are fitted with Class 2 closing appliances and the length of the poop to the bulkhead is 0.5L or less, 100 per cent of that length shall be the effective length; where the length is 0.7L, or more, 90 per cent of that length shall be the effective length; where the length is between 0.5L and 0.7L, an intermediate percentage of that length shall be the effective length; but where in any of these cases an allowance is given for an efficient adjacent trunk (see subsection (29)), only 90 per cent of the length to the bulkhead shall be the effective length. (21) Fifty per cent of the length of an open poop or of an open extension of a poop beyond an efficient bulkhead shall be the effective length of the open poop or of the extension, as the case may be. (22) Where, at the end of a raised quarter deck, there is an efficient intact bulkhead, the length of the raised quarter deck to the bulkhead shall be the effective length; where the bulkhead is not intact, the superstructure shall be regarded as a poop of less than standard height. (23) Where there is an efficient bulkhead at each end of a bridge and the access openings in the bulkheads are fitted with Class 1 closing appliances, the length between the bulkheads shall be the effective length. (24) Where the access openings in the forward bulkhead of a bridge are fitted with Class 1 closing appliances and the access openings in the after bulkhead are fitted with Class 2 closing appliances, the length between the bulkheads shall be the effective length; but where an allowance is given for an efficient trunk adjacent to the after bulkhead (see subsection (29)), 90 per cent of the length shall be the effective length; where the access openings in both bulkheads are fitted with Class 2 closing appliances, 90 per cent of the length between the bulkheads shall be the effective length; where the access openings in the forward bulkhead are fitted with Class 1 or Class 2 closing appliances and the access openings in the after bulkhead have no closing appliances, 75 per cent of the length between the bulkheads shall be the effective length; where the access openings in both bulkheads have no closing appliances, 50 per cent of the length shall be the effective length. (25) Seventy-five per cent of the length of an open extension beyond the after bulkhead of a bridge, and 50 per cent of that beyond the forward bulkhead, shall be the effective length. (26) Where, at the end of a forecastle, there is an efficient bulkhead and the access openings are fitted with Class 1 or Class 2 closing appliances, the length of the forecastle to the bulkhead shall be the effective length. (27) Where the closing appliances referred to in subsection (26) are not fitted at the end of a forecastle, the effective length shall be (a) if the sheer forward of amidships is not less than the standard sheer, 100 per cent of the length of the forecastle forward of 0.1L from the forward perpendicular; (b) if the sheer forward of amidships is half the standard sheer or less, 50 per cent of the length of the forecastle forward of 0.1L from the forward perpendicular; and (c) if the sheer forward of amidships is between the standard and half the standard sheer, the percentage of the length of the forecastle forward of 0.1L from the forward perpendicular, that is the same percentage as the actual sheer forward of amidships is to the standard sheer. (28) Fifty per cent of the length of an open extension beyond the bulkhead or beyond 0.1L from the forward perpendicular shall be the effective length. (29) A trunk or similar structure that does not extend to the sides of the ship shall be regarded as efficient provided that (a) the trunk is at least as strong as a superstructure; (b) the hatchways are in the trunk deck and comply with the requirements of sections 3 to 10 of this Schedule, and the width of the trunk deck stringer provides a satisfactory gangway and sufficient lateral stiffness; (c) a permanent working platform fore and aft fitted with guard rails is provided by the trunk deck or by detached trunks connected to other superstructures by efficient permanent gangways; (d) ventilators are protected by the trunk, by watertight covers or by equivalent means; (e) open rails are fitted on the weather portions of the freeboard deck in way of the trunk for at least half their length; and (f) the machinery casings are protected by the trunk, by a superstructure of standard height, or by a deck house of the same height and of equivalent strength. (30) Where access openings in poop and bridge bulkheads are fitted with Class 1 closing appliances, 100 per cent of the length of an efficient trunk reduced in the ratio of its mean breadth to B (as defined in subsection (3)), shall be added to the effective length of the superstructures; where the access openings in these bulkheads are not fitted with Class 1 closing appliances, 90 per cent of the length reduced as above shall be added. (31) Where the height of the trunk is less than the standard height, the addition referred to in subsection (30) shall be reduced in the ratio of the actual to the standard height; where the height of hatchway coamings on the trunk deck is less than the height of coamings as required by section 4 of this Schedule, a reduction from the actual height of trunk shall be made corresponding to the difference between the actual height of the coamings and the height required by section 4 of this Schedule. (32) A bridge structure that is `set in' shall be regarded as efficient provided that (a) the transverse amount of `set in' on each side of the ship at any point shall not exceed 305 mm inside the full breadth of the ship at that point; (b) the longitudinal extent of the `set in' shall not exceed the midship 4/10 of the length of the ship as defined in subsection (2); (c) the sides of the modified bridge shall be at least of equivalent strength to the normal bridge side construction and proper provisions shall be made for the maintenance and continuity of the strength of the ship; (d) the end bulkheads and closing appliances shall conform to the requirements of these Rules; and (e) the length of the bridge to be allowed in the assessment of the total length of superstructure shall be the effective length in accordance with subsections (23) to (25) multiplied by the factor where b is the breath of the modified superstructure at midships and B is the full breadth of the ship as defined in subsection (3). (33) Where there is an enclosed superstructure with one or more middle line openings in the deck not provided with permanent means of closing in accordance with sections 3 to 10 of this Schedule, effective length of superstructure is determined as follows: (a) where efficient temporary closing appliances are not provided for the middle line deck openings in accordance with subsection (14) or the breadth of opening is 80 per cent or more of the breadth (B1) of the superstructure deck at the middle of the opening, the ship shall be regarded as having an open well in way of each opening, and freeing ports shall be provided in way of this well; the effective length of superstructure between openings shall be ascertained by applying subsections (19) to (21) and (23) to (28); (b) where efficient temporary closing appliances as defined in subsection (14) are provided for middle line deck openings and the breadth of opening is less than 0.8B1, the effective length of superstructure between openings shall be ascertained by applying subsections (19) to (21) and (23) to (28) except that where access openings in 'tween deck bulkheads are closed by Class 2 closing appliances, they shall be regarded as being closed by Class 1 closing appliances; the total effective length shall be obtained by adding to the length thus determined the difference between that length and the length of the ship modified in the ratio of PART I CONDITIONS OF ASSIGNMENT General Conditions 2. The conditions of assignment set out in sections 3 to 26 shall be met by all ships before they are assigned freeboards. Openings in Freeboard and Superstructure Decks 3. The construction and fitting of cargo and other hatchways in exposed positions on freeboard and superstructure decks shall be at least equivalent to the standards laid down in sections 4 to 10. 4. (1) The height of hatchway coamings on freeboard decks shall be at least 610 mm above the deck; the height of coamings on superstructure decks shall be at least 610 mm above the deck if situated within a quarter of the ship's length from the stem, and at least 460 mm if situated elsewhere. (2) Coamings shall be of steel, shall be substantially constructed and, where required to be 610 mm high, shall be fitted with an efficient horizontal stiffener placed not lower than 254 mm below the upper edge, and with efficient brackets or stays from the stiffener to the deck, at intervals of not more than 3.05 m. 5. (1) Covers to exposed hatchways shall be efficient, and where they are made of wood, the finished thickness shall be at least 60 mm in association with a span of not more than 1.52 m, and the ends of the wood covers are to be protected by a galvanized steel band efficiently secured. The width of each bearing surface for these hatchway covers shall be at least 64 mm. (2) The provisions of subsection (1) requiring the ends of the wood covers to be protected by a galvanized steel band efficiently secured do not apply to wood hatch covers in use prior to January 1, 1949, but apply in all cases where such hatch covers are renewed. 6. Where wood hatchway covers are fitted, the hatchway beams and fore-and-afters shall be of the scantlings and spacings given in Table I to this section where coamings 610 mm high are required, and as given in Table II to this section where coamings 460 mm high are required; angle bar mountings on the upper edge shall extend continuously for the full length of each beam; wood fore-and-afters shall be steel shod at all bearing surfaces. TABLE I (COAMINGS, 610 mm IN HEIGHT) Hatchway Beams and Fore-and-Afters for Ships 61 M or More in Length * Hatchway Beams Breath of Mounting Hatchway Beams with Fore-and-Afters Beams without Fore-and-Afters Spacing Centre to Centre Spacing Centre to Centre 1.83m 2.44m 3.05m 1.22m 1.52m metres millimetres millimetres millimetres millimetres millimetres millimetres 3.05 75 x 75 x 10AC 280 x 7.5T 305 x 8T 356 x 8.5T 229 x 11.5TB 254 x12.5TB 3.66 75 x 75 x 10AC 305 x 8T 356 x 8.5T 432 x 9T 279 x 12.5TB 305x12.5TB 4.27 75 x 75 x 10.5AC 356 x 8.5T 432 x 9T 508 x 9.5T 305 x 12.5TB 305 x 8T 4.88 90 x 75 x 10.5AC 406 x 9T 483 x 9.5T 559 x 9.5T 305 x 8T 356 x 8.5T 5.49 100 x 75 x 11AC 457 x 9T 533 x 9.5T 635 x 10T 356 x 8.5T 406 x 9T 6.10 100 x 75 x 11AC 508 x 9.5T 610 x 10T 711 x 10.5T 381 x 8.5T 457 x 9T 6.71 115 x 75 x 11.5AC 559 x 9.5T 660 x 10.5T 762 x 11T 406 x 9T 483 x 9T 7.32 130 x 90 x 11.5AC 584 x 10T 711 x 10.5T 813 x 11T 432 x 9T 508 x 9.5T 7.92 140 x 90 x 12AC 610 x 10T 736 x 10.5T 864 x 11.5T 457 x 9T 533 x 9.5T 8.53 150 x 90 x 12.5AC 635 x 10T 787 x 11T 914 x 12T 483 x 9.5T 559 x 9.5T 9.14 150 x 90 x 13AC 660 x 10.5T 813 x 11T 965 x 12T 508 x 9.5T 584 x 10T FORE-AND-AFTERS Length Mounting Fore-And-Afters Bulb Plate-Centre Fore-And-Afters Bulb Angle-Side Fore-And-Afters Spacing Centre to Centre Spacing Centre to Centre 0.91m 1.22m 1.52m 0.91m 1.22m 1.52m metres millimetres millimetres millimetres millimetres millimetres millimetres millimetres 1.83 65x65x9 150x9 165x9.5 180x9.5 150x75x9.5 165x90x9.5 180x90x9.5 2.44 65x65x9.5 180x10.5 200x11 225x11 180x90x10.5 200x75x11 225x90x11 3.05 65x65x10 200x12.5 240x12.5 280x12.5 200x90x12.5 240x90x12.5 280x90x12.5 Length of Fore-and-Afters Wood Centre Fore-and-Afters Wood Side Fore-and-Afters Spacing Centre to Centre Spacing Centre to Centre 0.91m 1.22m 1.52m 0.91m 1.22m 1.52m D B D B D B D B D B D B metres mm mm mm mm mm mm mm mm mm mm mm mm 1.83 140 180 150 180 165 180 140 140 150 150 165 150 2.44 165 180 190 180 200 180 165 165 190 180 200 180 3.05 200 180 215 200 225 225 200 180 215 200 225 225 A=Plain Angle BP=Bulb Plate P=Plate D=Depth B=Breadth Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge. Depths for fore-and-afters are measured from the under side of the hatch-covers to the lower edge. Sizes for intermediate lengths and spacing are obtained by interpolation. Where plates are specified, two angles of the size given for mountings, are to be fitted at the upper and at the lower part of the beam. Where bulb plates are specified, two angles, of the size given for mountings, are to be fitted at the upper part of the beam or fore-and-after. Where bulb angles are specified, one angle, of the size given for mountings, is to be fitted at the upper part of the section. Where the specified flanges of an angle are of different dimensions, the large flange is to be horizontal. *In ships not exceeding 30.5 m in length, the depths of beams which are formed of plates and angles may be 60 per cent of the depths given above; the depths of beams and steel fore-and-afters formed of bulb angle or bulb plate section may be 80 per cent of the depths given above; the thickness of plates, bulb angles and bulb plates should correspond to the thickness tabulated for the reduced depths with a minimum thickness of 7.5 mm, the depths and breadths of wood fore-and-afters may be 80 per cent of those given in the tables for side fore-and-afters, but the centre fore-and-afters must not be less than 165 mm wide. In ships between 30.5 m and 61 m in length, the sizes of the beams and fore-and-afters are to be determined by linear interpolation. TABLE II (COAMINGS, 457 mm IN HEIGHT) Hatchway Beams and Fore-and-Afters for Ships 61 M or More in Length * Hatchway Breath of Mounting Hatchway Beams with Fore-and-Afters Beams without Fore-and-Afters Spacing Centre to Centre Spacing Centre to Centre 1.83m 2.44m 3.05m 1.22m 1.52m metres millimetres millimetres millimetres millimetres millimetres millimetres 3.05 75 x 75 x 10AC 240 x 11.5TB 267 x 12.5T 292 x 13TB 200 x 10TB 225 x 11TB 3.66 75 x 75 x 10AC 280 x 12.5TB 280 x 7.5T 330 x 8.5T 225 x 11TB 225 x 12.5TB 4.27 75 x 75 x 10.5AC 280 x 7.5T 330 x 8T 381 x 8.5T 254 x 12.5TB 292 x 12.5TB 4.88 90 x 75 x 10.5AC 305 x 8T 381 x 8.5T 432 x 9.T 280 x 7.5TB 280 x 7.5T 5.49 100 x 75 x 11AC 356 x 8.5T 432 x 9T 483 x 9.5T 280 x 7.5TB 305 x 8T 6.10 100 x 75 x 11AC 406 x 9T 483 x 9.5T 533 x 9.5T 305 x 8T 330 x 8.5T 6.71 115 x 75 x 11.5AC 432 x 9T 508 x 9.5T 584 x 10T 318 x 8T 356 x 8.5T 7.32 130 x 90 x 11.5AC 457 x 9T 533 x 9.5T 635 x 10T 330 x 8.5T 368 x 8.5T 7.92 140 x 90 x 12AC 483 x 9.5T 559 x 9.5T 660 x 10.5T 344 x 8.5T 381 x 8.5T 8.53 150 x 90 x 12.5AC 508 x 9.5T 584 x 10T 686 x 10.5T 356 x 8.5T 406 x 9T 9.14 150 x 90 x 13AC 533 x 9.5T 610 x 10T 711 x 10.5T 381 x 8.5T 432 x 9T FORE-AND-AFTERS A=Plain Angle BP=Bulb Plate P=Plate D=Depth B=Breadth Length Mounting Fore-And-Afters Bulb Plate-Centre Fore-And-Afters Bulb Angle-Side Fore-And-Afters Spacing Centre to Centre Spacing Centre to Centre 0.91m 1.22m 1.52m 0.91m 1.22m 1.52m metres millimetres millimetres millimetres millimetres millimetres millimetres millimetres 1.83 65x65x9 130x8.5 140x8.5 150x9 130x75x8.5 140x75x8.5 150x75x9 2.44 65x65x9.5 150x9.5 180x10 190x10.5 150x75x9.5 180x75x10 190x90x10.5 3.05 65x65x10 180x11 200x11.5 225x12.5 180x75x11 200x90x11.5 225x90x12.5 Length of Fore-and-Afters Wood Centre Fore-and-Afters Wood Side Fore-and-Afters Spacing Centre to Centre Spacing Centre to Centre 0.91m 1.22m 1.52m 0.91m 1.22m 1.52m D B D B D B D B D B D B metres mm mm mm mm mm mm mm mm mm mm mm mm 1.83 130 180 140 180 150 180 130 130 140 130 150 130 2.44 150 180 165 180 180 180 150 130 165 150 180 150 3.05 180 180 190 180 200 180 180 150 190 180 200 180 Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge. Depths for fore-and-afters are measured from the under side of the hatch-covers to the lower edge. Sizes for intermediate lengths and spacing are obtained by interpolation. Where plates are specified, two angles, of the size given for mountings, are to be fitted at the upper and at the lower part of the beam. Where bulb plates are specified, two angles, of the size given for mountings, are to be fitted at the upper part of the beam or fore-and-after. Where bulb angles are specified, one angle, of the size given for mountings, is to be fitted at the upper part of the section. Where the specified flanges of an angle are of different dimensions, the large flange is to be horizontal. In ships not exceeding 30.5 m in length, the depths of beams which are formed of plates and angles may be 60 per cent of the depths given above; the depths of beams and steel fore-and-afters formed of bulb angle or bulb plate section may be 80 per cent of the depths given above; the thickness of plates, bulb angles and bulb plates should correspond to the thickness tabulated for the reduced depths with a minimum thickness of 7.5 mm; the depths and breadths of wood fore-and-afters may be 80 per cent of those given in the tables for side fore-and-afters, but the centre fore-and-afters must not be less than 165 mm wide. In ships between 30.5 m and 61 m in length, the sizes of the beams and fore-and-afters are to be determined by linear interpolation. 7. Carriers or sockets for hatchway beams and fore-and-afters shall be of steel at least 13 mm thick, and shall have a width of bearing surface of at least 75 mm. 8. Strong cleats at least 64 mm wide shall be fitted at intervals of not more than 610 mm from centre to centre; the end cleats shall be placed not more than 150 mm from each corner of the hatchway; and, in the case of a ship whose keel is laid after January 1, 1949, the cleats shall be of a pattern approved by the Assigning Authority and shall be set to fit the taper of the wedges. 9. (1) Battens and wedges shall be efficient and in good condition. (2) In the case of a ship whose keel is laid after January 1, 1949, wedges shall be made from tough wood cut to a taper of 1 in 6 and shall be not less than 13 mm thick at the toe. (3) At least two tarpaulins in good condition, thoroughly waterproofed and of ample strength, shall be provided for each hatchway in an exposed position on freeboard and superstructure decks; the material of the tarpaulins shall be guaranteed free from jute, and the minimum weight of the material, before treatment, shall be 644 g/m2 if to be tarred, 610 g/m2 if to be chemically dressed or 542 g/m2 for black oil dressing. 10. (1) Where coamings are required to be 610 mm high, steel bars or other equivalent means shall be provided for efficiently and independently securing each section of hatchway covers after the tarpaulins are battened down. (2) At all other hatchways in exposed positions on freeboard and superstructure decks, ring bolts or other fittings for lashings shall be provided. (3) Where hatchway covers extend over intermediate supports, steel bars or their equivalent shall be fitted at each end of each section of the covers. (4) The provisions of subsections (1) and (3) apply to a ship whose keel is laid after January 1, 1949; and such provisions shall also apply to any other ship if, in the opinion of the Assigning Authority, compliance with such provisions is reasonable and practicable, provided that where full compliance is not considered to be reasonable and practicable, efficient means for securing the hatchway covers after the tarpaulins are battened down shall be provided in the form of fittings for special lashings to the satisfaction of the Assigning Authority. 11. (1) Cargo, coaling and other hatchways in the freeboard deck within superstructures that are fitted with closing appliances less efficient than Class 1 but not less efficient than Class 2 shall have coamings at least 230 mm in height and closing arrangements as effective as those required for exposed cargo hatchways whose coamings are 460 mm high. (2) Where the closing appliances are less efficient than Class 2, the hatchways shall have coamings at least 460 mm in height, and shall have fittings and closing arrangements as effective as those required for exposed cargo hatchways. 12. (1) Machinery space openings in exposed positions on freeboard and raised quarter decks shall be properly framed and efficiently enclosed by steel casings of ample strength; doors in such casings shall be of steel, efficiently stiffened, permanently attached, and capable of being closed and secured from both sides; the sills of openings shall be at least 610 mm above the freeboard deck and at least 460 mm above the raised quarter deck. (2) Fiddley, funnel and ventilator coamings shall be as high above the deck as is reasonable and practicable; fiddley openings shall have strong steel covers permanently attached in their proper positions. 13. (1) Machinery space openings in exposed positions on superstructure decks other than raised quarter decks shall be properly framed and efficiently enclosed by strong steel casings; doors in such casings shall be strongly constructed, permanently attached, and capable of being closed and secured from both sides; the sills of the openings shall be at least 380 mm above superstructure decks. (2) Fiddley, funnel and ventilator coamings shall be as high above the deck as is reasonable and practicable; fiddley openings shall have strong steel covers permanently attached in their proper positions. 14. Machinery space openings in the freeboard deck within superstructures that are fitted with closing appliances less efficient than Class 1 shall be properly framed and efficiently enclosed by steel casings; doors in such casings shall be strongly constructed, permanently attached and capable of being securely closed; the sills of the openings shall be at least 230 mm above the deck where the superstructures are closed by Class 2 closing appliances, and at least 380 mm above the deck where the closing appliances are less efficient than Class 2. 15. (1) Flush bunker scuttles may only be fitted in superstructure decks, except in the case of small ships in special trades when they may be fitted in other positions by permission of the Assigning Authority. (2) Such scuttles shall be of iron or steel, of substantial construction, with screw or bayonet joints; where a scuttle is not secured by hinges, a permanent chain attachment shall be provided. 16. Companionways in exposed positions on freeboard decks and on decks of enclosed superstructures shall be of substantial construction; the sills of the doorways shall be of the heights specified for hatchway coamings in sections 4 and 11; the doors shall be strongly constructed and capable of being closed and secured from both sides; where the companionway is situated within a quarter of the ship's length from the stem, it shall be of steel and riveted to the deck plating. 17. (1) Ventilators in exposed positions on freeboard and superstructure decks to spaces below freeboard decks or decks of superstructures that are intact or fitted with Class 1 closing appliances shall have coamings of steel, substantially constructed, and efficiently connected to the deck by rivets spaced 4 diameters apart centre to centre, or by equally effective means; the deck plating at the base of the coaming shall be efficiently stiffened between the deck beams; the ventilator openings shall be provided with efficient closing arrangements. (2) Where such ventilators are situated on the freeboard deck, or on the superstructure deck within a quarter of the ship's length from the stem, and the closing arrangements of the ventilators are of a temporary character, the coamings shall be at least 915 mm in height; in other exposed positions on the superstructure deck they shall be at least 760 mm in height; where the coaming of any ventilator exceeds 915 mm in height, it shall be specially supported and secured. 18. Where the air pipes to ballast and other tanks extend above freeboard or superstructure decks, the exposed parts of the pipes shall be of substantial construction; the height from the deck to the opening shall be at least 915 mm in wells on freeboard decks, 760 mm on raised quarter decks, and 460 mm on other superstructure decks; efficient means shall be provided for closing the openings of the air pipes. Openings in the Sides of Ships 19. Openings in the sides of ships such as gangways, cargo ports, coaling ports, rubbish chutes or ash chutes that are below the freeboard deck shall be fitted with watertight doors or covers that, with their securing appliances, shall be of sufficient strength. 20. (1) Scuppers and sanitary discharge pipes led through the ship's sides from spaces below the freeboard deck shall be fitted with efficient and accessible means for preventing water from passing inboard; each separate discharge shall have either an automatic non-return valve with a positive means of closing it from a position above the freeboard deck, or two automatic non-return valves without positive means of closing, provided that the upper valve is situated so that it is always accessible for examination under service conditions; the positive action valve shall be readily accessible and shall be provided with means for showing whether the valve is open or closed; cast iron shall not be accepted for such valves when attached to the sides of the ship. (2) The provisions of subsection (1) apply to discharges from spaces within enclosed superstructures if and to the extent that the Assigning Authority considers necessary, having regard to the type and location of the inboard ends of such openings. (3) Where scuppers are fitted in superstructures not fitted with Class 1 closing appliances, they shall have efficient means for preventing the accidental admission of water below the freeboard deck. (4) In the case of a ship whose keel is laid after January 1, 1949, cast iron shall not be used for valves and discharges led through the ship's sides below the freeboard deck or through the sides of enclosed superstructures. 21. (1) Side scuttles to spaces below the freeboard deck, or to spaces below the superstructure deck of superstructures closed by Class 1 or Class 2 closing appliances, shall be fitted with efficient inside deadlights permanently attached in their proper positions so that they can be effectively closed and secured watertight. (2) Where, however, such spaces in superstructures are appropriated to passengers, other than steerage passengers, or to crew, the side scuttles may have portable deadlights stowed adjacent to the side scuttles, provided that they are readily accessible at all times on service. (3) The side scuttles and deadlights shall be of substantial construction and of types approved by the Board. Miscellaneous Provisions 22. Efficient guard rails and bulwarks shall be fitted on all exposed portions of freeboard and superstructure decks. 23. (1) Where bulwarks on the weather portions of freeboard or superstructure decks form "wells", ample provision shall be made for rapidly freeing the decks of water and for draining them; the minimum freeing port area on each side of the ship for each "well" on freeboard decks and on raised quarter decks shall be that given by the following scale; the minimum area for each well on any superstructure deck other than a raised quarter deck shall be one-half the area given by that scale; where the length of the well exceeds seven-tenths of the length of the ship, the Assigning Authority may modify that scale; in ships with less than the standard sheer, the freeing port area shall be increased as required by the Assigning Authority. SCALE OF FREEING PORT AREA Length of bulwarks in "well" in metres Freeing port area on each side in square metres 5 0.750 6.5 0.795 8 0.840 9.5 0.885 11 0.930 12.5 0.975 14 1.020 15.5 1.065 17 1.110 18.5 1.155 20 1.200 Above 20 0.090m2 for each additional 1.5 m length of bulwark (2) The lower edges of the freeing ports shall be as near the deck as practicable and as a general rule shall not be higher than the upper edge of the gunwale bar; two-thirds of the freeing port area required shall be provided in the midship half of the well. (3) All such openings in the bulwarks shall be protected by rails or bars spaced about 230 mm apart; where shutters are fitted to freeing ports, ample clearance shall be provided to prevent jamming; hinges shall have brass pins. 24. (1) Gangways, lifelines or other satisfactory means shall be provided for the protection of the crew in getting to and from their quarters. (2) The strength of houses for the accommodation of crew on flush deck steamships shall be equivalent to that required for superstructure bulkheads. 25. Notwithstanding anything in this Part, the Assigning Authority may, in any exceptional case, allow departures from the provisions thereof on condition that the freeboards computed for the ship are increased to such extent as will, in the opinion of the Board, secure that the protection afforded to the ship and crew is not less effective than it would be if the ship fully complied with the said provisions and there had been no increase of freeboards. 26. (1) The Assigning Authority shall be satisfied with the structural strength of any ship before assigning to it a freeboard. (2) Ships that comply with the highest standard of the rules of a classification society authorized pursuant to section 421 of the Act shall be regarded as having sufficient strength for the minimum freeboards allowed under these Rules. (3) Ships that do not comply with the highest standard of the rules of a classification society authorized as aforesaid shall be assigned such increased freeboards as shall be determined by the Assigning Authority, having regard to the extent to which the ship complies with the following strength moduli: (a) Material--The strength moduli are based on the assumption that the structure is built of mild steel, manufactured by the open hearth process (acid or basic), and having a tensile strength of 401 to 494 MPa, and an elongation of at least 16 per cent on a length of 203 mm. Strength Deck--The strength deck is the uppermost deck which is incorporated into and forms an integral part of the longitudinal girder within the half-length amidships. Depth to Strength Deck (Ds)--The depth to strength deck is the vertical distance in metres amidships from the top of the keel to the top of the strength deck beam at side. Draught (d)--The draught is the vertical distance in metres amidships from the top of the keel to the centre of the disc. (b) Longitudinal Modulus--The longitudinal modulus is the moment of inertia I of the midship section about the neutral axis divided by the distance y measured from the neutral axis to the top of the strength deck beam at side, calculated in way of openings but without deductions for rivet holes. Areas are measured in square centimetres and distances in metres. Below the strength deck, all continuous longitudinal members other than such parts of the under deck girders as are required entirely for supporting purposes are included. Above the strength deck, the gunwale angle bar and the extension of the sheerstrake are the only members included. The required longitudinal modulus for effective material is expressed by the formula f.d.B., where f is the factor obtained from the following table: TABLE L f L f 30.50 38.10 109.73 198.96 36.58 42.33 115.82 218.01 42.67 49.74 121.92 237.05 48.77 57.15 128.02 257.17 54.86 66.67 134.11 277.28 60.96 76.20 140.21 299.51 67.06 88.90 146.30 320.67 73.15 101.60 152.40 343.96 79.25 115.35 158.50 367.25 85.34 131.23 164.59 390.53 91.44 147.10 170.69 414.87 97.54 162.98 176.78 440.27 106.63 180.97 182.90 465.67 For intermediate lengths, the value of f is determined by interpolation. This formula applies where L does not exceed 182.9 m, B is between (c) Frame--For the purpose of the frame modulus, the frame is regarded as composed of a frame angle and a reverse angle each of the same size and thickness. frame below the lowest tier of beams is the moment of inertia I of the frame section about the neutral axis divided by the distance y measured from the neutral axis to the extremity of the frame section, calculated without deduction for rivet and bolt holes. The modulus is measured in centimetre units. The required frame modulus is expressed by the formula: where s is the frame spacing in metres; t is the vertical distance in metres measured at amidships from the top of the keel to a point midway between the top of the inner bottom at side and the top of the heel bracket (see Figure 4); where there is no double bottom, t is measured to a point midway between the top of the floor at centre and the top of the floor at side; f1 is a coefficient depending on H, which, in ships fitted with double bottoms, is the vertical distance in metres from the middle of the beam bracket of the lowest tier of beams at side to a point midway between the top of the inner bottom at side and the top of the heel bracket (see Figure 4). Where there is no double bottom, H is measured to a point midway between the top of the floor at centre and the top of the floor at side. Where the frame obtains additional strength from the form of the ship, due allowance is made in the value of f1; f2 is a coefficient depending on K, which is the vertical distance in metres from the top of the lowest tier of beams at side to a point 2.29 m above the freeboard deck at side, or, if there is a superstructure, to a point 3.81 m above the freeboard deck at side (see Figure 4). The values of f1 and f2 are obtained from the following table: TABLE H in metres 0 2.133 2.743 3.353 3.962 4.572 5.182 5.791 6.401 7.010 7.620 f1 19 053 23 287 26 464 31 758 40 227 50 810 62 455 76 219 91 035 107 970 124 900 K in metres 0 1.524 3.048 4.572 6.096 7.620 9.144 10.668 12.192 f2 0 1 058.5 2 117 4 234 6 351 9 527 13 761 19 053 25 407 Intermediate values are obtained by interpolation. This formula applies where D is between 4.57 m and 18.29 m, both inclusive, B is between both inclusive, is between 10 and 13.5, both inclusive; and the horizontal distance from th General Load Line Rules (CRC Vol. XVI c. 1425) - Canada Shipping Regulations.