Ship Safety Bulletins (SSB)
Date (Y-M-D): 1990-05-23
Subject: Securing of Slack Grain with Wire Reinforcement Mesh
Further to Ship Safety Bulletin No. 15/86, notice has recently been given to the International Maritime Organization, in accordance with Regulation 5 of SOLAS 1974, that the securing of slack grain with wire reinforcement mesh is considered by Canada as an acceptable equivalent to the timber platform and that prior written approval from the ship's flag Administration is no longer necessary.
However, some Administrations may not permit this method and on their ships the traditional method of securing, as described in Schedule II - Part II of the Grain Cargo Regulations, will still be required.
To date, no Administrations have advised that they will not permit this method of securing.
When slack grain is to be secured utilizing wire reinforcement mesh, the method should be as described in Ship Safety Bulletin No. 15/86, repeated hereunder.
- Prior to the completion of loading, lashings as described in the Grain Cargo Regulations are to be positively attached to the framing approximately 450 mm below the anticipated final grain surface by means of either 25 mm shackles or beam clamps of equivalent strength spaced not more than 2.4 m apart. It is important that the lashings at the hold ends be located close to the bulkheads in order to adequately restrain the ends of the top layer of mesh.
- The grain shall be trimmed and levelled with a slight crown at the centreline and covered with burlap separation cloths, tarpaulins or the equivalent that overlap at least 1.8 m. Burlap or equivalent material shall also be laid around frames and bulkhead corrugations.
- At each frame space and bulkhead corrugation two 25 mm x 150 mm (or heavier) timber battens of approximately 2.5 m in length shall be laid so that they project into the space in such a manner that they best secure the burlap at the frames.
- An athwartship layer of wire mesh of approximately 150 mm x 150 mm squares of 10 gauge wire, shall be laid. Individual runs of meshing shall overlap about 75 mm onto the neighbouring run. The mesh shall extend right up to the frames and be sufficiently nailed to the 25 mm x 150 mm battens to maintain its laid position.
- Wire mesh as described in (4), shall be laid fore and aft extending from bulkhead to bulkhead, overlapping each run by about 75 mm secure with seizing wire sufficient to keep the mesh in the laid position.
- Fore and aft at the edge of the frames and athwartships at the positions of the foremost and aftermost lashings, next to the bulkheads, perimeter boards of at least 50 mm x 150 mm timber shall be laid. These boards must effectively hold down the frame space battens. The individual lengths of perimeter boards shall be overlapped onto the next length and nailed.
- In way of each lashing point, an athwartship bearer board of 50 mm x 150 mm timber shall be laid, overlapped and nailed where necessary and nailed onto the perimeter boards at the outboard ends.
- Turnbuckles and staple nails shall be tensioned lightly to the bearer boards. The staple nailing shall be sufficient to locate the wire over the board, but not sufficient to prevent retensioning of the wire.
When wire reinforcement mesh is to be used, the following authority is to be notified before such work commences:
Superintendent, Cargoes & Containers, AMSFB
Canadian Coast Guard - Ship Safety
344 Slater St., 12th floor
Ottawa, Ontario
KlA ON7
Telex: 053-3128
Fax: 613-993-8196
Keywords: Questions concerning this bulletin should be addressed to:
2. Wire
3. Mesh
Marine Safety
Tower C, Place de Ville
11th Floor, 330 Sparks Street
Ottawa, Ontario K1A 0N8
To add or change your address, contact us at: marinesafety@tc.gc.ca
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