Chapter 3 - Important factors to consider when evaluating FRP elements with starting point in the regulations of SOLAS chapter II-2
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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 - Chapter 3 - Important factors to consider when evaluating FRP elements with starting point in the regulations of SOLAS chapter II-2

Chapter 3 - Important factors to consider when evaluating FRP elements with starting point in the regulations of SOLAS chapter II-2

 The different fire safety regulations in SOLAS chapter II-2 have been analysed with the intention to identify important factors that could be necessary to address when using FRP elements in ship structures. These factors are described in the following paragraphs. Each of the regulations with prescriptive requirements (regulations 4 to 23) starts with a purpose statement. Each purpose statement consists of a regulation objective and one or several regulation functional requirements. The purpose statements have been reproduced for each regulation followed by comments on how a ship with FRP elements may challenge the regulation. The regulations are not only investigated based on potential deviations and how these may have an effect on safety but also in a broader sense, i.e. how a ship with FRP composite structures could affect the regulations' purpose statements or envisioned purpose.

Note that this investigation of the regulations is not complete and may not cover all relevant effects on fire safety for a certain design and arrangements with FRP composite structures. The intention is for these guidelines to be developed, concretized and updated based on the regulations. In particular, some of the regulations could be investigated in more detail and from different perspectives.

3.1 Regulation 1 – Application

There are currently no comments to this regulation with regard to FRP composite.

3.2 Regulation 2 – Fire safety objectives and functional requirements

Paragraph 2 states a number of functional requirements which are embodied in the regulations of the fire safety chapter in order to achieve the fire safety objectives set out in paragraph 1. In particular, the third functional requirement (regulation 2.2.1.3) requires restricted use of combustible material. The fire safety objectives and the functional requirements can be achieved by ensuring compliance with all prescriptive requirements in parts B, C, D, E and G or by alternative design and arrangements which comply with part F (regulation 17). Approval in accordance with regulation 17 still requires that the alternative design and arrangements meet the fire safety objectives and the functional requirements but allows doing so in a different way than in accordance with the prescriptive requirements.

In evaluating the achievement of the fire safety objectives and the functional requirements from a broad perspective, it may be stated that a ship with FRP elements may achieve some better and some worse than a traditional design. The focus on safety of human life in the fire safety objectives makes it topical to address not only the safety of passengers, but also the safety of firefighters and crew. Consideration of the functional requirements especially indicates that risks from adding combustible materials need to be accounted for.

3.3 Regulation 3 – Definitions

From the definitions in this regulation a few details may be useful to recapitulate with regard to FRP composite:

  • 3.2 From the definition of "A" class divisions it should be noted that such divisions are described to be constructed of "steel or other equivalent material" and that they should be so constructed as to be capable to preventing the passage of smoke and flame to the end of the one-hour standard fire test.

  • 3.4 From the definition of "B" class divisions it should be noted that such divisions are described to be constructed of "approved non-combustible materials" and that they should be so constructed as to be capable to preventing the passage of smoke and flame to the end of the first half hour of the standard fire test.

  • 3.10 From the definition of "C" class divisions it should be noted that such divisions are described to be constructed of "approved non-combustible materials" and that no other requirements apply.

  • 3.33 From the definition of non-combustible material it should be noted that such material is described to neither burn nor to give off flammable vapours in sufficient quantity for self-ignition when heated to approximately 750°C.

  • 3.43 From the definition of steel or other equivalent material it should be noted that the phrase refers to any non-combustible material which, by itself or due to insulation provided, has structural and integrity properties equivalent to steel at the end of the applicable exposure to the standard fire test. Therefore, there are requirements regarding non-combustibility as well as structural and integrity properties. Note that the former is not limited in time but the latter requirements need only be achieved until the end of the applicable exposure of the standard fire test. An aluminium alloy with appropriate insulation is used to exemplify an equivalent material to steel.

  • 3.47 From the definition of a standard fire test it is described to be a test in which specimens of the relevant bulkheads or decks are exposed in a test furnace to temperatures corresponding approximately to the standard time-temperature curve.

3.4 Regulation 4 – Probability of ignition

Purpose statement:

The purpose of this regulation is to prevent the ignition of combustible materials or flammable liquids. For this purpose, the following functional requirements shall be met:

  • .1 means shall be provided to control leaks of flammable liquids;

  • .2 means shall be provided to limit accumulation of flammable vapours;

  • .3 the ignitability of combustible materials shall be restricted;

  • .4 ignition sources shall be restricted;

  • .5 ignition sources shall be separated from combustible materials and flammable liquids; and

  • .6 the atmosphere in cargo tanks shall be maintained out of the explosive range.

Comments:

1 Using combustible materials for structures is not in conflict with the objective of this regulation. However, it states to aim at preventing the ignition of combustible materials. Looking at the prescriptive requirements, they prevent the occurrence of fire by restricting ignition sources and some combustibles. Mainly fuels and the handling of highly flammable substances are concerned, but also a few miscellaneous items in enclosures. Most are ignition sources and the only actual combustible material concerned is primary deck coverings. If applied within accommodation, service or control spaces or on cabin balconies, they shall not readily ignite (regulation 4.4.4). This requirement may seem a bit illogical since a primary deck covering is the first layer fitted on a deck, used to smooth out unevenness, and covered by a floor construction. It is rather the surface of the floor construction which may be exposed to a potential ignition source. Furthermore, the requirement implies the primary deck coverings should have low flame-spread characteristics, which is a requirement that fits better in regulation 5. However, apart from this requirement, there are no other prescriptive requirements to be found on how the ignitability of combustible materials shall be restricted, as stated amongst the functional requirements in the purpose statement.

2 New hazards may be introduced where FRP composite is used close to significant ignition sources, such as exhaust pipes or other high-temperature surfaces. It may be argued that this challenges the functional requirement on separation of ignition sources from combustible materials. Due to assumptions regarding the use of non-combustible structures, this safety function is not clearly stated in prescriptive requirements of this regulation. It is nevertheless important to identify ignition sources and ensure that FRP composite surfaces are properly protected.

3 It may be argued that leaving combustible FRP composite surfaces unprotected is not in line with the functional requirement concerning restricted combustibility. However, this rather concerns ignition sources and easily ignitable (e.g. by a small flame) combustibles and flammable substances whilst combustible materials which have restricted ignitability, such as FRP composite, are managed in regulation 5. It is noted that an IMO test method for evaluation of restricted ignitability of products does not exist.

3.5 Regulation 5 – Fire growth potential

Purpose statement:

The purpose of this regulation is to limit the fire growth potential in every space of the ship. For this purpose, the following functional requirements shall be met:

  • .1 means of control for the air supply to the space shall be provided;

  • .2 means of control for flammable liquids in the space shall be provided; and

  • .3 the use of combustible materials shall be restricted.

Comments:

1 This regulation oversees materials and other items in spaces with the intention to limit the fire growth potential. Looking at the functional requirements, neither of the first two is affected by use of FRP elements in ship constructions. However, the third functional requirement must be taken into account as it states that the use of combustible materials shall be restricted. The definition of a non-combustible material is given in regulation 3.33 and defines it as a material that neither burns nor gives off flammable vapours when heated to 750°C. For example, vinyl ester, which is often used as resin in FRP composite, will give rise to pyrolysis gases above 500°C.

2 In the prescriptive requirements, use of non-combustible and combustible materials is primarily managed in paragraph 3. Except interiors and furnishings, the requirements concern linings, grounds, draught stops, ceilings, faces, mouldings, decorations, veneers, insulation materials, partial bulkheads, etc. These are also the materials that will govern the growth phase of a fire, together with, for example, luggage and other loose fittings. In general, all surfaces and linings in accommodation and service spaces must fulfil requirements of a maximum calorific value of 45 MJ/m2, a maximum volume of combustible material and have low flame-spread characteristics according to the FTP Code. However, since the regulations assume that the bulkhead plate behind any wall construction is steel, there are no requirements regarding the materials behind the wall construction.

3 The requirements in this regulation could be claimed to apply to surfaces of any sort. Therefore, if the same approved materials for linings, grounds, draught stops, ceilings, faces, mouldings, decorations, veneers, etc. are used in a ship with FRP composite constructions as in a traditional (prescriptive) design, it could be claimed that the design complies with the prescriptive requirements in regulation 5. This would generally not increase the fire growth potential in the spaces in the initial stages during evacuation. However, if the FRP composite surfaces are left uncovered or if divisions are constructed with combustible FRP composite just underneath surfaces of low flame-spread characteristics, it can be argued that the surface laminate in fact represents the surface lining, to which requirements regarding low flame-spread characteristics and maximum volume of combustible material apply; the requirement on maximum calorific value would then apply to the core. With this reasoning all of these requirements would generally be deviated.

4 As mentioned above, thermal insulation may be used to provide structural integrity, which will also protect the combustible FRP composite surfaces from fire involvement, e.g. for 60 minutes. In this case the FRP composite will not add to the fire growth potential in the space within the first hour of a fire having the same intensity as a standard fire test curve.

5 As mentioned above, this regulation covers materials and other items in spaces with the intention to limit the fire growth potential. All discussions above have considered internal spaces. Since external surfaces on ships are typically made up of painted steel there has not been any reason to regulate this matter. This is another example of where the FRP composite goes beyond the steel-based regulations. Making exterior surfaces in combustible FRP composite will affect the fire growth potential and could cause vertical fire spread between decks, which is a hazard that must be addressed on these ships. Hazardous exterior surfaces could for example be protected to achieve low flame-spread characteristics or be protected with drencher system. An indirect way to manage the problem is to use fire rated windows, which could avoid fire spread.

3.6 Regulation 6 – Smoke generation potential and toxicity

Purpose statement:

The purpose of this regulation is to reduce the hazard to life from smoke and toxic products generated during a fire in spaces where persons normally work or live. For this purpose, the quantity of smoke and toxic products released from combustible materials, including surface finishes, during fire shall be limited.

Comments:

1 Similarly to regulation 5, the prescriptive requirements of regulation 6 mostly concern enclosures. All materials involved in a fire will contribute to the production of toxic smoke but during the first stages of a fire it is mainly the exposed surface that will contribute to the generation and toxicity of smoke. This regulation generally controls exposed surface finishes and primary deck coverings.

2 FRP composites could either be covered with approved surface materials or left unprotected. In spaces where the FRP composite is left unprotected, it could be difficult to fulfil regulation 6.2.1. Furthermore, if an approved surface material is used on the FRP composite, it may be argued that the regulations are predicated on that a non-combustible material is used for the ship structures that are underneath. The generation and toxicity of smoke may, depending on the construction, therefore not be limited to the same extent as in a prescriptive design during an enclosure fire.

3 When scrutinizing regulations 5 and 6, it is important to realize that both regulations manage smoke production but where the latter mainly has to do with the individual material characteristics, it could be said that regulation 5 manages so that an unlimited area of combustible materials does not catch fire and produce smoke and that regulation 6 manages the potential of each square meter that can be involved in a fire.

4 Thermal insulation may be used to protect the combustible FRP composite surfaces from becoming involved in a fire. For the time that the construction is thermally protected, the FRP composite will not add to the generation or toxicity of the produced smoke. In the event of a fire lasting long enough to involve the FRP composite divisions, an increased generation and toxicity of smoke could be argued to occur, in comparison with a steel ship. This will depend on the selection of plastic materials. For instance, PVC is known to release highly toxic hydrochloric acid (HCl) during combustion.

5 It is hard to predict whether the smoke generation and toxicity at a given time would be worse in a ship with FRP elements compared to a steel ship depending on the insulating capacity of the construction. If thermal insulation is used to protect the FRP composite, fire spread will likely be delayed. It could be noted that when a fire starts to involve the protected FRP composite divisions, conditions will already have been uninhabitable for a while. An increased smoke generation or toxicity could be hazardous to persons on the embarkation deck depending on wind direction.

6 Fires on open deck and involving exterior surfaces in FRP composite could also be affected by the smoke generation and toxicity. However, this problem may not be as relevant when considering exteriors, since smoke management is not critical.

3.7 Regulation 7 – Detection and alarm

Purpose statement:

The purpose of this regulation is to detect a fire in the space of origin and to provide for alarm for safe escape and firefighting activity. For this purpose, the following functional requirements shall be met:

  • .1 fixed fire detection and fire alarm system installations shall be suitable for the nature of the space, fire growth potential and potential generation of smoke and gases;

  • .2 manually operated call points shall be placed effectively to ensure a readily accessible means of notification; and

  • .3 fire patrols shall provide an effective means of detecting and locating fires and alerting the navigation bridge and fire teams.

Comments:

In general, use of FRP composite does not present any deviations from prescriptive requirements. However, the functional requirements give reason to oversee the need for detection. Considering the first regulation functional requirement, there is no reason to believe that significantly less smoke is produced by FRP composites than organic materials in general. However, since the fire growth potential in some areas may be affected, there may also be an additional need for detection. For areas where non-insulated FRP elements are used, it is particularly critical to provide early activation of an extinguishing system with quick detection. It may therefore be relevant with faster or more reliable smoke detection or to provide it in additional areas of the ship, possibly even in open spaces or void spaces. The potential increased need for detection should be considered in the fire risk assessment and depends on how FRP composite is used.

3.8 Regulation 8 – Control of smoke spread

Purpose statement:

The purpose of this regulation is to control the spread of smoke in order to minimize the hazard from smoke. For this purpose, means for controlling smoke in atriums, control stations, machinery spaces and concealed spaces shall be provided.

Comments:

As discussed in 3.6 (regulation 6 – Smoke generation potential and toxicity) the amount of smoke generated in a fire test with FRP composite structures (glass fibre reinforced polyester with PVC core) was only slightly larger than that from a fire in a steel ship. If this is the case for the alternative design and arrangements being evaluated, this would indicate that the current requirements for control of smoke spread could be met.

3.9 Regulation 9 – Containment of fire

Purpose statement:

The purpose of this regulation is to contain the fire in the space of origin. For this purpose the following requirements shall be met:

  • .1 the ship shall be divided by thermal and structural boundaries;

  • .2 thermal insulation boundaries shall have due regard to the fire risk of the space and adjacent spaces; and

  • .3 the fire integrity of the division shall be maintained at openings and penetrations.

Comments:

1 This regulation prescribes main vertical and horizontal zones and, where necessary, internal bulkheads to be made up by divisions of "A" class standard. "A" class means that steel or other equivalent material shall be used. Regulation 3.43 defines steel or other equivalent material as a non-combustible material which, by itself or by insulation provided, has structural and integrity properties equivalent to those of steel at the end of the standard fire test. Unprotected FRP composite generally ignites when exposed to significant fire but could for example be combined with thermal insulation in order to gain fire integrity comparable with "A" class standard. Tests have demonstrated that the temperature rise at the unexposed side of a FRD60 (cf. HSC Code) division will be as low as 45°C after 60 minutes of fire exposure (temperature rise and integrity test in accordance with the standard test for bulkheads and decks, see the Test procedures for fire-resisting divisions of high-speed craft (MSC 45(65)). This low conduction of heat will prevent heat from being transferred long distances through the ship structure, which may be a fire risk in conventional ships.

2 The low conductivity of a FRD60 division can also give rise to a faster fire development within the enclosed space, equivalent to an insulated aluminium structure or a heavily insulated steel structure (e.g. "A-60" class). When insulation or any protective surface layer is deteriorated and the surface temperature of the FRP composite reaches its ignition temperature, the FRP composite will start contributing to the fire, which could also accelerate the fire development if additional oxygen is available.

3 Specific fire integrity and insulation requirements for internal decks and bulkheads depend on a classification made of the spaces and are given in tables in regulation 9. The way spaces are assigned fire categories may need to be reconsidered, in particular for spaces with added fire load by exposed untreated FRP composite. This includes open decks.

4 If FRP composite is used on open deck, all connections between interior and external spaces must be reconsidered. Design of windows, doors and ventilation systems may, for example, need to be reconsidered due to the potential external fire hazards, i.e. due to potential spread of smoke and fire into the ship or out to external surfaces.

5 Regarding penetrations in fire-resisting divisions, doors, pipes, window frames, etc. are generally also required to be non-combustible when penetrating "A" class divisions. The integration of such penetrations into an FRP composite division must be documented by fire tests or potentially by engineering judgement. The integration of doors, windows, cable glands, ducts, fire dampers and pipes in FRP composite fire divisions has been successfully demonstrated in tests.

6 A robust integration of the insulation systems onto an FRP composite fire division is crucial. The effect of voids between insulation and the composite structure could be further evaluated. Essential systems in a fire situation, such as sprinkler systems, piping and ducts, must have a fastening/support system that is designed not to fail in case of a fire.

3.10 Regulation 10 – Firefighting

Purpose statement:

The purpose of this regulation is to suppress and swiftly extinguish fire in the space of origin. For this purpose the following requirements shall be met:

  • .1 fixed fire-extinguishing systems shall be installed, having due regard to the fire growth potential of the spaces; and

  • .2 fire-extinguishing appliances shall be readily available.

Comments:

1 The first functional requirement states that the fixed fire-extinguishing systems shall have due regard to the fire growth potential of the space. It is only if the fire growth potential differs significantly that it is necessary to take into account FRP composites when designing the fire-extinguishing systems. In most cases, fire growth in the FRP composite will not be dimensioning for the fire-extinguishing system since more rapid fire developments can generally occur in other combustibles and since the size of a fire depends on the oxygen supply. The fire pump capacity and pressure requirements should therefore generally not need to be changed. However, since early extinguishment is important, it may still be suitable to oversee the firefighting systems and that extinguishment is managed properly.

2 It may also be necessary to consider fire-extinguishing systems and equipment in additional places of a ship with FRP composite constructions. If exterior surfaces are made of FRP composite they may need to be protected in order to prevent an enclosure fire from spreading to the exteriors if a door or window is left open or broken, e.g. by a sprinkler above the openings. It may also be relevant to install drencher systems covering essential parts of the hull or exteriors of superstructure, if there is a risk of fire spread or deterioration of structural performance.

3 Even though the purpose statements and prescriptive requirements of this regulation only cover fire-extinguishing systems and appliances, it is in the context of the regulation title also relevant to consider effects on manual firefighting routines. There are a few significant differences:

  • .1 First and foremost, the need to perform defensive boundary cooling from the outside of a fire enclosure is removed. It is instead important to have an offensive strategy to provide direct cooling of the fire. Boundary cooling is a strategy that requires many resources without actually fighting the fire, but mainly hindering fire spread. A much more efficient way to fight a fire is to quickly reach inside the enclosure. With traditional equipment this may not be possible due to the heat or risk of fire spread if a door is opened. However, there is more suitable firefighting equipment already in use, such as the Cutting Extinguisher or Fog Spear. Tests have demonstrated that firefighting by such equipment through small holes in the FRP composite boundaries is very effective. The holes may be pre-fabricated or made by equipment on site. This will allow dampening the fire from outside of the fire origin. Suitable equipment in combination with a rerouting of firefighting resources relieved from boundary cooling to either assist in active combat of the fire may increase both effectiveness and efficiency.

  • .2 Furthermore, a fire which has taken root in the FRP composite may be difficult to fully extinguish. This implies more resources will be needed to keep watch over fire-scorched areas to ensure that the FRP composite does not reignite. This may not significantly interfere with the critical stages of taking control of the fire.

  • .3 Another aspect of how firefighting routines could be affected is that the improved thermal resistance of FRP composite structures could imply difficulties in finding the seat of the fire from adjacent compartments with a commonly used thermal imaging camera.

  • .4 Routines regarding potential collapse must also be developed in order to insure the safety of passengers and firefighting crew.

4 All in all, the ability to focus more resources on actively fighting the fire, combined with the introduction of tools to cool hot fire gases from an adjacent compartment could improve the efficiency and effectiveness of firefighting in ships with FRP composite structures. In any case, effects on firefighting routines must be taken into consideration when making ship structures in FRP composite.

5 Additional equipment for manual firefighting could also be necessary, e.g. in open deck spaces surrounded by FRP composite surfaces.

3.11 Regulation 11 – Structural integrity

Purpose statement:

The purpose of this regulation is to maintain structural integrity of the ship, preventing partial or whole collapse of the ship structures due to strength deterioration by heat. For this purpose, the materials used in the ships' structure shall ensure that the structural integrity is not degraded due to fire.

Comments:

1 This regulation intends to ensure that structural integrity is maintained in case of a fire. After the purpose statement of the regulation, paragraph 2 of regulation 11 states that:

  • "The hull, superstructures, structural bulkheads, decks and deckhouses shall be constructed of steel or other equivalent material. For the purpose of applying the definition of steel or other equivalent material as given in regulation 3.43, the 'applicable fire exposure' shall be according to the integrity and insulation standards given in tables 9.1 to 9.4. For example, where divisions such as decks or sides and ends of deckhouses are permitted to have 'B-0' fire integrity, the 'applicable fire exposure' shall be half an hour."

2 Structures shall thus be constructed of steel or other equivalent material, i.e. any non-combustible material which, by itself or due to insulation provided, has structural and integrity properties equivalent to steel at the end of the standard fire test. This prescriptive requirement cannot be complied with if combustible FRP composite structures are used. The existing fire tests within the FTP Code for A and B class divisions are conducted over a period of up to 60 minutes. Structural and integrity properties equivalent to steel may be achieved for such a time of fire exposure in the standardized test, for example if the FRP composite is sufficiently insulated. However, unlike the requirements on structural and integrity properties, the requirement on non-combustibility is not time-limited. The fire tests do not assess the performance of the material after the end of the test, nor when subject to load.

3 Insulated steel divisions may lose fire integrity after for example 60 min; not due to strength deterioration by heat but due to possible fire spread to adjacent compartments by heat transfer. A prolonged fire could involve and deteriorate an FRP composite structure when thermal insulation or other means are no longer enough to provide structural and integrity performance. A large enough fire could then bring about a local collapse.

4 Steel generally loses its structural strength at about 400°C to 600°C and an unstiffened FRP composite sandwich panel may lose bonding between core and laminate, and thereby structural performance, when heated to about 150°C (or a temperature where the bonding between core and laminate starts to soften). Improved structural integrity of FRP composite structures may be achieved by use of e.g. stiffeners, pillars or additional layers but steel ships have proved to be able to survive fire for several days without progressive structural collapse occurring. This is particularly important when considering that the ship shall retain safe areas for the refuge of passengers (SOLAS regulation II-2/21.5), including control stations to remain intact and habitable for command and control activities necessary during an incident. This can for example affect the measures required to achieve successful evacuation of the ship (cf. HSC Code). It is crucial that fire hazards introduced in case of a long-lasting fire (lasting for more than 60 minutes) are addressed in the SOLAS regulation II-2/17 assessment.

5 Deviations from prescriptive requirements are found in regulation 11.4 if steel (not "steel or other equivalent material") is not used for structures forming crowns, casings and floor plating of machinery spaces of category A. Use of FRP composite for such structures may need special consideration.

6 Further to the above, steel-FRP joints need to be assessed in detail to ensure that structural fire integrity is achieved (see also section B.3.4 of appendix B).

3.12 Regulation 12 – Notification of crew and passengers

Purpose statement:

The purpose of this regulation is to notify crew and passengers of a fire for safe evacuation. For this purpose, a general emergency alarm system and a public address system shall be provided.

Comments:

There are no obvious challenges posed to this regulation by the use of FRP composite. However, a public address system may be indirectly affected if special instructions must be made to avoid passengers to reside in certain areas where there is a risk of collapse. An exterior fire could also affect the possibility of using certain exterior areas or life-saving appliances.

3.13 Regulation 13 – Means of escape

Purpose statement:

The purpose of this regulation is to provide means of escape so that persons on board can safely and swiftly escape to the lifeboat and liferaft embarkation deck. For this purpose, the following functional requirements shall be met:

  • .1 safe escape routes shall be provided;

  • .2 escape routes shall be maintained in a safe condition, clear of obstacles; and

  • .3 additional aids for escape shall be provided as necessary to ensure accessibility, clear marking, and adequate design for emergency situations.

Comments:

1 This regulation aims to provide means for persons to safely and swiftly escape a fire, assemble and proceed to their embarkation station. Considering the prescriptive requirements, regulation 13.3.1.3 requires all stairways in accommodation spaces, service spaces and control stations to be of steel frame construction or other equivalent material sanctioned by the Administration. If they are made of FRP composites they need to be evaluated in the fire safety analysis. The same applies to stairways and ladders in machinery spaces (regulation 13.4.1). However, such constructions are generally not considered in other materials than steel, even on ships in FRP composite. It may be noted that safe havens and escape ways manufactured from composites are used in the offshore industry.

2 In order to achieve safe escape routes, regulation 13 requires fire integrity and insulation in several places, referring to values in regulation 9 (tables 9.1 to 9.4). A sufficiently insulated FRP composite division could be claimed to achieve these requirements (since non-combustibility is not required).

3 In an FRP composite structure the temperature on the unexposed side could, due to the high insulation capacity of the composite construction, be very low even after 60 minutes of fire. The heat from a fire will therefore to a larger extent stay in the fire enclosure and not easily be transmitted to adjacent spaces. This could be advantageous in an escape situation.

3.14 Regulation 14 – Operational readiness and maintenance

Purpose statement:

The purpose of this regulation is to maintain and monitor the effectiveness of the fire safety measures the ship is provided with. For this purpose the following functional requirements shall be met:

  • .1 fire protection systems and firefighting systems and appliances shall be maintained ready for use; and

  • .2 fire protection systems and firefighting systems and appliances shall be properly tested and inspected.

Comments:

The functional requirements are not affected by use of FRP composite. The fire protection systems and firefighting systems and appliances must be maintained ready for use and should be properly tested and inspected on a ship with FRP composite structures, as on any ship. Even if the regulation may be directly applied and no deviations are posed, the content covered by this regulation may be affected. Depending on the alternative design and arrangements, there may be a need for faster extinguishment, increased capacity or improved reliability and consequently more maintenance.

3.15 Regulation 15 – Instructions, onboard training and drills

Purpose statement:

The purpose of this regulation is to mitigate the consequences of fire by means of proper instructions for training and drills of persons on board in correct procedures under emergency conditions. For this purpose, the crew shall have the necessary knowledge and skills to handle fire emergency cases, including passenger care.

Comments:

Except for the need for increased knowledge of firefighters considering strategies, techniques, routines, etc. (see 4.10), there are no direct differences on a ship with FRP composite structures in comparison with a traditionally built ship. In similarity with regulation 14, the content covered by this regulation may be affected depending on the systems considered in the alternative design and arrangements.

3.16 Regulation 16 – Operations

Purpose statement:

The purpose of this regulation is to provide information and instructions for proper ship and cargo handling operations in relation to fire safety. For this purpose, the following functional requirements shall be met:

  • .1 fire safety operational booklets shall be provided on board; and

  • .2 flammable vapour releases from cargo tank venting shall be controlled.

Comments:

There are no known challenges posed to this regulation for a ship with FRP composite structures. In similarity with regulation 14, the content covered by this regulation may nevertheless be affected depending on the solutions considered in the alternative design and arrangements.

3.17 Regulation 17 – Alternative design and arrangements

Purpose statement:

The purpose of this regulation is to provide a methodology for alternative design and arrangements for fire safety.

Comments:

The method described in regulation 17 (and MSC.1/Circ.1002, as amended by MSC.1/Circ.1552) and its suitability when assessing fire safety in FRP composite constructions is discussed in appendix C to these guidelines.

3.18 Regulation 18 – Helicopter facilities

Purpose statement:

The purpose of this regulation is to provide additional measures in order to address the fire safety objectives of this chapter for ships fitted with special facilities for helicopters. For this purpose, the following functional requirements shall be met:

  • .1 helideck structure shall be adequate to protect the ship from the fire hazards associated with helicopter operations;

  • .2 firefighting appliances shall be provided to adequately protect the ship from the fire hazards associated with helicopter operations;

  • .3 refuelling and hangar facilities and operations shall provide the necessary measures to protect the ship from the fire hazards associated with helicopter operations; and

  • .4 operation manuals and training shall be provided.

Comments:

Helicopter decks have previously been built with FRP composite materials on non-SOLAS ships but will require special evaluations, including testing, and tailored detection and extinguishment.

3.19 Regulation 19 – Carriage of dangerous goods

Purpose statement:

The purpose of this regulation is to provide additional safety measures in order to address the fire safety objectives of this chapter for ships carrying dangerous goods. For this purpose, the following functional requirements shall be met:

  • .1 fire protection systems shall be provided to protect the ship from the added fire hazards associated with carriage of dangerous goods;

  • .2 dangerous goods shall be adequately separated from ignition sources; and

  • .3 appropriate personnel protective equipment shall be provided for the hazards associated with the carriage of dangerous goods.

Comments:

None of the prescriptive requirements are likely to be affected by use of FRP composite constructions. However, there may be reason to evaluate potential hazards from leakage of dangerous goods onto an FRP composite deck, not only from a fire perspective. Certain dangerous goods may for example cause the FRP composite to deteriorate if they come in contact. These and other hazardous non-fire related scenarios must be considered. With regard to fire, the time to collapse may change due to a potentially larger fire involving combustible surrounding exterior FRP composite surfaces.

3.20 Regulation 20 – Protection of vehicle, special category and ro-ro spaces

Purpose statement:

The purpose of this regulation is to provide additional safety measures in order to address the fire safety objectives of this chapter for ships fitted with vehicle, special category and ro-ro spaces. For this purpose, the following functional requirements shall be met:

  • .1 fire protection systems shall be provided to adequately protect the ship from the fire hazards associated with vehicle, special category and ro-ro spaces;

  • .2 ignition sources shall be separated from vehicle, special category and ro-ro spaces; and

  • .3 vehicle, special category and ro-ro spaces shall be adequately ventilated.

Comments:

This regulation describes requirements for ventilation, alarm and detection systems, fire-extinguishing equipment and structural requirements for spaces with vehicles. In passenger ships carrying more than 36 passengers, the boundary bulkheads or decks of the ro-ro space are by regulation 20.5 required to achieve A-60 (with some exceptions where the structural fire protection can be reduced to A-0). This cannot be achieved if such divisions are made of FRP composite. Furthermore, even if not required by prescriptive requirements, it may prove necessary to better address the first regulation functional requirement by passive or active measures, e.g. by an additional active fire-extinguishing system on exterior surfaces. For ro-ro spaces which are not of special category, the fire safety requirements are different and in generally considered less stringent.

3.21 Regulation 21 – Casualty threshold, safe return to port and safe areas

Purpose statement:

The purpose of this regulation is to establish design criteria for a ship's safe return to port under its own propulsion after casualty that does not exceed the casualty threshold stipulated in paragraph 3 and also provides functional requirements and performance standards for safe areas.

Comments:

Passenger ships constructed on or after 1 July 2010 having a length of 120 m or above or having three or more main vertical zones, shall comply with this regulation. However, FRP composite may be used in superstructures of the ship. In any case, it may be relevant to evaluate e.g. whether the definition of the casualty threshold in regulation 21.3 is appropriate for ships in FRP composite. Furthermore, structural integrity is important to consider (see section 3.11) when considering safe areas for the refuge of passengers (regulation 21.5), including control stations to remain intact and habitable for command and control activities necessary during an incident.

3.22 Regulation 22 – Design criteria for systems to remain operational after a fire casualty

Purpose statement:

The purpose of this regulation is to provide design criteria for systems required to remain operational for supporting the orderly evacuation and abandonment of a ship, if the casualty threshold, as defined in regulation 21.3, is exceeded.

Comments:

Passenger ships constructed on or after 1 July 2010 having a length of 120 m or above or having three or more main vertical zones, shall comply with this regulation. However, FRP composite may be used in superstructures of the ship. In any case, it may be relevant to evaluate, e.g. whether there are additional hazards from the potential fire size and potential smoke production from FRP structures with regard to evacuation and abandonment.

3.23 Regulation 23 – Safety centre on passenger ships

Purpose statement:

The purpose of this regulation is to provide a space to assist with the management of emergency situations.

Comments:

Passenger ships constructed on or after 1 July 2010 shall have a safety centre on board complying with the requirements of this regulation. From the safety centre all fire safety systems should be available, such as ventilation systems, alarm systems, fire detection and alarm systems, fire and emergency pumps, etc. In general, this is not affected by the FRP composite construction material, but it may be necessary to consider collapse when determining the location of the safety centre.


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