SOLAS Chapter II-1 – Construction – Structure, Subdivision and Stability, Machinery and Electrical Installations

1 Regulation 1.3 – Application

For conversions of single-hull oil tankers to double-hull oil tankers or bulk carriers, the following should apply:

.1 Conversions of single-hull oil tankers to double-hull oil tankers or bulk carriers should be regarded as modifications of a major character for the purposes of SOLAS chapter II-1.
.2 Repairs, alterations and modifications of a major character include:
- .1 Substantial alteration of the dimensions of a ship, for example lengthening of a ship by adding a new midbody. The new midbody should comply with SOLAS chapter II-1.
- .2 A change of ship type, for example an oil tanker converted to a bulk carrier. Any structure, machinery and systems that are added or modified should comply with SOLAS chapter II-1, taking into account the interpretation of SOLAS chapter II-1 regulations as contained herein.

2 Regulations 3-2.2 and 3-2.4 – Protective coatings of dedicated seawater ballast tanks in all types of ships and double-side skin spaces of bulk carriers

2.1 For single-hull oil tanker conversion into double-hull oil tanker, SOLAS regulation II-1/3-2 as adopted by resolution MSC.216(82) should apply to dedicated water ballast tanks if constructed with all structural members being entirely new. If converting existing spaces into water ballast tanks with part of the existing structural members remaining in place, revised SOLAS regulation II-1/3-2 (MSC.216(82)) need not be applied. However, dedicated seawater ballast tanks should have an efficient corrosion prevention system such as hard protective coatings or equivalent and be of light colour.

2.2 For single-hull oil tanker conversion into bulk carrier, SOLAS regulation II-1/3-2 as adopted by resolution MSC.216(82) should apply to dedicated water ballast tanks and double-side skin spaces of bulk carriers if constructed with all structural members being entirely new. If converting existing spaces into dedicated water ballast tanks or double-side skin space of bulk carriers with part of the existing structural members remaining in place, revised SOLAS regulation II-1/3-2 (MSC.216(82)) need not be applied. However, dedicated seawater ballast tanks should have an efficient corrosion prevention system such as hard protective coatings or equivalent and be of light colour.

3 Regulation 3-6 – Access to and within spaces in, and, forward of, the cargo area of oil tankers and bulk carriers

3.1 For single-hull oil tanker conversion into double-hull oil tanker

3.1.1 Permanent means of access contained in table 1 of the Technical provisions for means of access for inspections (resolution MSC.158(78)) need not apply. However, if, in the course of conversion, substantial new structures are added, these new structures should comply with the regulation.

3.1.2 The term "substantial new structures" means hull structures that are entirely renewed or augmented by new double bottom and/or double-side construction (e.g. replacing the entire structure within cargo area or adding a new double bottom and/or double-side section to the existing cargo area).

3.1.3 Additionally, an approved Ship Structure Access Manual should be provided.

3.2 For single-hull oil tanker conversion into bulk carrier

3.2.1 Permanent means of access contained in table 2 of the Technical provisions for means of access for inspections (resolution MSC.158(78)) need not apply. However, if, in the course of conversion, substantial new structures are added, these new structures should comply with the regulation.

3.2.2 The term "substantial new structures" means hull structures that are entirely renewed or augmented by new double bottom and/or double-side skin construction (e.g. replacing the entire structure within cargo area or adding a new double bottom and/or double-side section to the existing cargo area).

3.2.3 Additionally, an approved Ship Structure Access Manual should be provided.

4 Regulation 3-8 – Towing and mooring equipment

For single-hull oil tanker conversion into double-hull oil tanker or bulk carrier

This regulation should be applied when equipment and fittings for mooring/towing are replaced, modified or the safe working load of the existing equipment and fittings is known. Where the latter cannot be ascertained, alternative compliance with SOLAS regulation II-1/3-8 should be sought (e.g. the equipment should be replaced, tested or modified).

5 Part B – Subdivision and stability

5.1 For single-hull oil tanker conversion into double-hull oil tanker

Oil tankers complying with damage stability requirements contained in Annex I to MARPOL 73/78 (except for combination carriers with type B freeboards) may be excluded from the damage stability requirements contained in SOLAS chapter II-1, part B-1.

5.2 For single-hull oil tanker conversion into bulk carrier

5.2.1 A bulk carrier which is assigned a B reduced freeboard complying with damage stability requirements contained in regulation 27 of the 1966 Load Line Convention, and resolutions A.320(IX) and A.514(13); or regulation 27 of the 1988 Load Line Protocol, may be excluded from the damage stability requirements contained in SOLAS chapter II-1, part B-1.

5.2.2 For a bulk carrier which is assigned a B freeboard, SOLAS chapter II-1, parts B and B-1 should be applied.