APPENDIX A. Instructions for the construction of life-rafts. B. Instructions for the construction of buoyant apparatus. D. Table of squares and cubes. E. Decimals of a foot for each one sixty-fourth of an inch. A. COPY OF CIRCULAR INSTRUCTIONS, No. 1586, ISSUED BY THE MARINE DEPARTMENT OF THE BOARD OF TRADE IN NOVEMBER, 1917. By permission of the Controller of His Majesty's Stationery Office. LIFE-RAFTS. General Rule 2 of the Life-saving Appliances Rules provides that when one or more life-rafts are accepted in lieu of a lifeboat, such life-rafts must be in every respect as efficient as the pontoon life-raft described in General Rule 10. Life-rafts must be of a type approved by the Board and should be constructed under the supervision and to the satisfaction of the Surveyors. Before the construction of a new type of life-raft is commenced, a specification and a fully detailed drawing of the raft, accompanied by a report from the Surveyor, should be submitted to the Board for approval. A raft, when completed, will be subjected to such tests of efficiency as the Board may direct, and will be required to be in all respects satisfactory before being accepted as an approved life-saving appliance. The Surveyors are to be guided by the following instructions which interpret the sections of General Rule 10. The following paragraphs numbered I. to V. apply to life-rafts the construction of which is commenced after the 1st January, 1918 I. Bulwarks. The bulwarks must admit of easy erection and the arrangements for supporting them are to be strong and efficient. The bulwarks and their supports must not be liable to be broken or rendered unfit by the raft being thrown into the water from the height required by these instructions. The bulwarks are not to be less than 18 in. in height above the top of the platform. II. Size, weight, strength and materials. An approved life-raft is required to be of such size and weight that it can be handled without mechanical appliances, and accordingly the weight of a life-raft in pounds, exclusive of equipment, is not to exceed the perimeter of the raft in feet measured on the line of the hand-holds, multiplied by 42, with a maximum of 15 cwts. A sample life-raft of each type and size adopted, and at least one in every ten similar rafts completed, is to be tested for strength by being dropped into the water on a deck, as well as on a side and end, in the presence of a Surveyor. In the case of new rafts the height from which the raft is dropped is to be not less than the height of the deck on which it will be stowed above the vessel's highest continuous deck, or 30 feet, whichever is the greater. The height for the drop test is to be measured in each case from the lowest point of the raft to the water. It is desirable that the builders satisfy themselves regarding the strength by subjecting the raft to private tests before complete official tests are witnessed. Rafts should be constructed of materials which do not quickly deteriorate by exposure to weather. If, however, the Surveyor is of opinion that the original strength of a raft has been materially reduced by exposure to the weather for a long period, or for any other reason, he should require the drop test to be repeated, but in such cases a drop equal to three-fourths the height specified above may be regarded as sufficient. An approved life-raft must be able to withstand the drop tests without being materially damaged. The Surveyor should carefully examine the raft after the test, and should inspect the air-cases, if fitted, for signs of distortion or leakage. All life-rafts are to be fitted with hand-holds or other means of lifting; and the Surveyor should satisfy himself that such rafts can be lifted and carried to the vessel's side with reasonable ease. Life-rafts are to be so constructed that they may be easily launched over the vessel's side; and there should, therefore, be no projections on a raft which would seriously hamper the operation of sliding it over the rail or gunwale. III. Buoyancy. The buoyancy of life-rafts is to be provided by means of air-cases or by some method of equal efficiency approved by the Board. If air-cases are fitted they are to be of copper or yellow metal of not less than 18 ozs. per square foot, or of equally durable material, properly strengthened by a wood transverse frame, and constructed generally as required for internal buoyancy for open lifeboats as prescribed in the Board's Instructions as to the Construction of Wooden Lifeboats (Circular 1575). The air-cases are to be easily accessible for periodical inspection. The required capacity of air-cases stated by the Rule is the minimum; a much larger capacity may be necessary to comply with the requirements of paragraph 1 (iv.) of General Rule 10. IV. Platform, construction and height of-The platform or deck is to be such as to provide a proper foothold for the persons upon it. Where the deck is close-planked, means are to be provided for quickly draining water off the deck. A sample life-raft of each pattern adopted is to be weighed and the freeboard to the top of the platform is to be ascertained, the raft being loaded with weights equivalent to the number of persons for whom the raft is deemed sufficient, at 165 lbs. for each person, and to the equipment. Unless the Surveyor is satisfied that the platform of the raft when loaded will be more than 6 in. above the water level, and the weight of the raft less than the limit allowed by these Instructions, these tests should be repeated for at least one in every ten similar rafts constructed. V. Stability and tests. An approved life-raft must have a sufficient margin of buoyancy and stability when laden with the equipment and the number of persons for whom it is deemed sufficient. A specimen of every new type of life-raft is to be inclined in the presence of a Surveyor in order that the stability of the raft may be ascertained. The raft when inclined should be in service condition and laden with metal weights equivalent to the total number of persons, at 165 lbs. for each person, and to the equipment, and the weights should be disposed vertically on the assumption that the centre of gravity of the occupants of the raft will be 2 ft. above the top of the deck or platform. VI. Equipment.-Proper means are to be fitted for stowing the equipment of each life-raft, as required by General Rules 14 (3), 14 (5), and loose articles of equipment are to be securely attached to the raft in such a way that the process of launching will not cause the loss of any of them. If provision and water tanks are fitted in the raft they should be accessible from either side; special regard should be given, however, to the strength and watertightness of the covers, which should be carefully screwed up before a drop test is made. The length of boat hook and oars need not exceed the maximum inside dimension of the deck. Rowing crutches should be of special pattern so that the raft can be easily rowed. For this purpose the height of the oar in the crutch should not be less than 12 in. above the deck, and holes with lacing eyes should be provided in canvas bulwarks at this height. A double row of life-lines should be strongly secured all round the raft, the loops being of such a length that the floats of the upper row will be on the surface of the water at whatever draft the raft may be floating. VII. Slings.-Life-rafts are to be fitted with strong slings or strops and strong eye-bolts so that, if circumstances permit, they may be lowered by means of davits, cranes, or derricks. If the rafts are not stowed under davits, cranes or derricks, a strong T-shaped bollard is to be provided abreast of each raft station. VIII. Existing life-rafts. As regards life-rafts already constructed, or of which the construction was commenced before the issue of these Instructions, the Surveyors should note that, while the foregoing explanatory paragraphs I. to V. may not strictly apply, no life-raft is in future to be accepted as part of the statutory equipment of a vessel unless it satisfies the conditions of General Rule 19 or unless it has been approved by the Board as being in every respect as efficient as the life-raft described in that Rule. IX. Marking. When the Surveyor has satisfied himself that the construction of a life-raft is in all respects satisfactory, he is to see that the raft is permanently marked as required by the Rules. The Surveyor should then complete the marking with his official stamps by adding his initials, the date, etc. X. Stowage of life-rafts. The Surveyors should note that General Rule 12 requires, inter alia, that rafts shall be stowed in such a way that they can be launched in the shortest possible time. Time and circumstances may in some cases permit of rafts being lowered into the water by means of davits or cranes, but in other circumstances it may be necessary to throw the rafts overboard, and it is desirable that provision should be made for both these methods of launching. Rafts must also be stowed securely but in such a manner that they can quickly be made free to float off the vessel in case of sudden foundering. A raft which does not exceed the weight specified in these instructions may be stowed inboard provided there is sufficient surrounding space to enable it to be lifted, and that there is no obstruction which would prevent the raft being carried to the ship's side with reasonable ease. Subject to the foregoing paragraph, rafts not exceeding the weight specified may be stowed one upon another, but they are not to be stowed three in a height unless special appliances are fitted for handling them and unless the arrangements have first received the Board's approval. Rafts are to be properly secured by gripes having slip links, or in some equally efficient manner, and where one raft is stowed above another the arrangements should be such, if practicable, that the release of a single set of gripes will set free both rafts. Efficient means are to be fitted, in the form of cants bolted to the deck or otherwise, to prevent the rafts moving transversely, or in a fore-and-aft direction, owing to the heeling or trimming of the vessel after the gripes have been removed. When one raft is stowed upon another, means must also be fitted to prevent the upper raft sliding off the lower one after the gripes have been removed. Rafts should be provided with efficient covers to protect them from the weather. XI. Certificate of approval.-If a pontoon life-raft is constructed and equipped in the manner indicated in paragraphs numbered I. to VII., tested in accordance with paragraphs II. and V. of these instructions, with satisfactory results, and complies with the conditions described in General Rule 10 of the Statutory Rules, the owner, if he desires it, may be granted a certificate of approval. The maker will be required to submit a detailed specification and drawings of the raft which, subject to the Board's approval, will be annexed to the certificate of approval. He will also be required to furnish the Board with 300 copies of the certificate, including the specification and drawings, for distribution to the Board's Surveyors. The fee for a certificate is five pounds (£5), and should be paid when application is made (on form Surveys 6) for the official tests to be witnessed by the Surveyors. B. COPY OF CIRCULAR INSTRUCTION, No. 1587, ISSUED BY THE MARINE DEPARTMENT OF THE BOARD OF TRADE IN DECEMBER, 1917. By permission of the Controller of His Majesty's Stationery Office. BUOYANT APPARATUS. The Life-saving Appliances Rules require a Home Trade passenger ship to carry boats, approved life-rafts, approved buoyant deck seats or other approved buoyant apparatus sufficient to accommodate the whole or a proportion (according to the Class in which the ship is placed) of the total number of persons for which the ship is certified. General Rule 15 defines approved buoyant apparatus follows:- 66 as Approved buoyant apparatus, whether buoyant deck seats, buoyant deck chairs or other buoyant apparatus, shall be deemed sufficient, so far as buoyancy is concerned, for a person or a number of persons to be ascertained by dividing the number of pounds of iron which it is capable of supporting in fresh water by 32. Such buoyant apparatus shall be of approved material and construction, and if it depends for its buoyancy on air shall not require to be inflated before use, and shall be marked in such a way as plainly to indicate that it is buoyant, and the number of persons for which it is approved. |