Section 2 Materials and protection

2.1.1 Materials, grades of steel and protection of materials are to comply with the requirements of Pt 3, Ch 2 Materials and the Rules for the Manufacture, Testing and Certification of Materials, July 2022.

2.2.1 The requirements of Pt 3, Ch 2, 3.6 Application of coatings and alternative means of protection and Ch 15 Corrosion Prevention of the Rules for Materials are to be complied with.

2.3.1 Aluminium may, under certain circumstances give rise to incendive sparking on impact with steel, the following requirements are therefore to be complied with:

1. Aluminium fittings in tanks used for the carriage of oil and in cofferdams and pump-rooms are to be avoided wherever possible.

2. Where fitted, aluminium fittings, units and supports, in tanks used for the carriage of oil, cofferdams and pump-rooms are to satisfy the requirements specified in Pt 3, Ch 2, 3 Corrosion protection for aluminium anodes.

3. The danger of mistaking aluminium anodes for zinc anodes must be emphasised. This gives rise to increased hazard if aluminium anodes are inadvertently fitted in unsuitable locations.

4. The underside of heavy portable aluminium structures such as gangways, etc. is to be protected by means of hard plastic or wood cover in order to avoid the creation of smears when dragged or rubbed across steel, which if subsequently struck, may create an incendive spark. It is recommended that such protection be permanently and securely attached to the structures.

2.3.2 For permissible locations of aluminium anodes, see Pt 3, Ch 2, 3.4 Aluminium and magnesium anodes.

2.3.3 Paint containing aluminium should not be used in positions where cargo vapours may accumulate unless it has been shown by appropriate tests that the paint to be used does not increase the incendive sparking hazard. Tests need not be performed for coatings containing less than 10 per cent aluminium by weight.

2.4.1 The suitability of coatings and their compatibility with intended cargoes are the responsibility of the Builder and the Owner. LR will, however, require the confirmation of the coating manufacturers that coatings which are used to protect the cargo tank structure are in order for the list of defined cargoes. A copy of the coating manufacturer's product resistance list is to be placed on board.

2.4.2 Attention is drawn to the requirements of Pt 3, Ch 11, 7.1 Materials 7.1.4 in respect of compatibility of cargoes and hatch packing materials. The packing material is to be resistant to both the liquids and vapours to which it is exposed.

2.4.3 Some plastics and rubbers are unsuitable for certain cargoes other than oil. In such cases the manufacturer's advice should be sought.

2.4.4 Some materials or their alloys are unsuitable for certain cargoes other than oil. Where such cargoes are to be carried, the use of these materials is not permitted in locations where they may come into contact with the cargo or its vapours, see also Pt 4, Ch 9, 1.1 General 1.1.7.