Appendix A - Issues Other Than Fire Safety
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Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1574 – Interim Guidelines for Use of Fibre Reinforced Plastic (FRP) Elements Within Ship Structures: Fire Safety Issues – (9 June 2017) - Annex - Interim Guidelines for Use of Fibre Reinforced Plastic (FRP) Elements Within Ship Structures: Fire Safety Issues - Appendix A - Issues Other Than Fire Safety

Appendix A - Issues Other Than Fire Safety

 1 Use of FRP composite may affect other parts of a ship's safety than those associated with fire. Potential issues are listed below, categorized as issues which are indirectly related to fire safety and issues which are unrelated to fire safety. It should be noted that the list of issues in this appendix is not exhaustive and is meant to be used as an example.

2 An example of an issue indirectly related to fire safety is:

  • If, for example, additional drencher systems are installed in combination with FRP composite, drainage and pumping arrangements may need to be installed in the same manner as in SOLAS regulations II-2/19 and II-2/20.

3 Issues unrelated to fire safety are:

  • .1 Water intrusion over time in FRP elements:

    • Experience with FRP has demonstrated that resin-fibre construction may absorb water over the years. This moisture is believed to be the source of free water found in otherwise sound voids.

  • .2 Required use of steel or other equivalent material in the International Convention on Load Lines 1966 (1966 LL Convention), which states:

    • .1 Regulation 12: All access doors in bulkheads at ends of enclosed superstructures shall be fitted with doors of steel or other equivalent material.

    • .2 Regulation 15: Pontoon hatch covers: Gives criterion for deflection (z-direction) due to uniformly distributed load on pontoon hatch covers. The formula (criterion) is assuming steel as material in the hatches.

    • .3 Regulation 16: Hatchways closed by weathertight covers of steel or other equivalent materials: gives criterion for deflection (z-direction) due to uniformly distributed load on pontoon hatch covers. The formula (criterion) is assuming steel as material in the hatches. In addition, hatch covers as per regulation 16 shall be made of steel or other equivalent materials.

    • .4 Regulation 19: Ventilators "shall be made of steel or other equivalent materials".

    • .5 Regulation 20: Air pipes "exposed parts of air pipes shall be of substantial construction".

    • These issues could be managed through the opening for performance-based design provided in regulation 2.4 of the 1966 LL Convention, which states "Ships of wood or of composite construction, or of other materials the use of which the Administration has approved, or ships whose construction features are such as to render the application of this annex unreasonable or impracticable, shall be assigned freeboards as determined by the Administration."

  • .3 Electromagnetic compatibility (EMC)

    • In a ship made of steel the hull acts as a counterpoise to external and internal electrical and radio interferences, e.g. lightning or EMC. In an FRP structure the same grounding mechanism is not present, which could interfere and cause problems for the radio communication, radar, fire detection system, automation, etc.

    • Special consideration is needed for addressing compliance with standards such as IEC-60533, stating for example that "complex electric and/or electronic systems require EMC planning in all phases of design and installation, considering the electromagnetic environment, any special requirements and the equipment performance."

  • .4 Radio communications.

  • .5 Radar issues might need reconsideration. For instance the radar might need adjustments and should be set up for sector transmission, due to radio wave transparency of the structure and radio frequency hazards.

  • .6 Electrical issues need to be reconsidered, for instance:

    • .1 grounding points (FRP structure being non-conductive), i.e. reconsider grounding of the equipment installed on board;

    • .2 insulation measurements; and

    • .3 lightning arrestors.

  • .7 Damage stability with regard to grounding and collision, floatability, structural integrity and impact strength:

    • .1 deformation due to unexpected high sea loads (same resistance to lateral pressure as implied by minimum thickness requirements may conservatively be provided); and

    • .2 deformations or other damage due to local contacts (same resistance to lateral pressure as implied by minimum thickness requirements may conservatively be provided).

    • Experience with the operation of HSLC of composite construction has demonstrated that, when minimum scantling requirements are complied with, no particular problems concerning robustness to local loads have been experienced.

  • .8 CO2 emissions and fuel efficiency.

  • .9 Life-saving arrangements.

Parent topic: Annex - Interim Guidelines for Use of Fibre Reinforced Plastic (FRP) Elements Within Ship Structures: Fire Safety Issues
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