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GRP lifesavers meet the challenge
GRP lifesavers meet the challenge Challenge: design a ship's lifeboat that can withstand being hurled (practically) from the deck of a ship or offshore installation, falling anything up to 47 m vertically and perhaps 20 m horizontally, with up to 8 0 people on board, and hitting the water at 6 0 mph plus - while keeping its occupants safe - and then clearing the area under its own power. Reinforced plastics make it possible says George Marsh. urprisingly, high-technology engineering composites are not needed for the free-fall lifeboats (FFLBs) now increasingly seen mounted, at a steep angle ready for instant launch, on the sterns of ships and on offshore installations. This latest type of lifeboat is normally constructed using 'standard' marine glass reinforced plastic (GRP) materials though material use is greater than with conventional ships' boats since FFLBs have to be totally enclosed and fortified to withstand high stresses at water entry. Ever since Titanic, those who go down to the sea in ships have been aware that
S
taking to the lifeboats can be a perilous operation. Boats swing, tip on unevenly surged wire cables, fall out of control, hit the ship's sides and sometimes, when the ship is listing, cannot be lowered on one side of the ship at all. (The 50% cut in capacity that could result has had to be allowed for ever since.) In 1976, prompted by several maritime disasters, the Norwegian Ship Research Institute tested an 11 m long boat intended for 'free-fall' launch, by letting it drop 20 m into Hardangar Fjord. A year later, the first manned launch of a free-fall lifeboat took place, from bulk carrier MS Tarcoola at Oresundsavarvet Shipyard.
'Hitting the water running' gives a better chance of saving lives should the worst happen, than relying on conventional lifeboats. The Norwegians had picked up on earlier work daring back to 1897 when AE Falk first patented an enclosed lifeboat capable of sliding off a ship's stern. Prior to World War II Captain White of the Bay and River Navigation Company had proposed the concept of a free-fall lifeboat (he called it a non-sinkable submarine lifeboat). A free-fall craft that clearly resembled a submarine, designed and tested by Dutch yacht builder Joseph 20
RBl~ORC~Dplastics
December 2001
Verhoef, went into service on a ship in 1961. But acceptance of the free-fall concept on any scale really began with the Norwegians' efforts in the '70s. By the early 1980s the new escape system, which could land in the water clear of any close debris or fire, was being installed offshore, the first facility to have it being the DV Delta, while the first use on a fixed installation in the North Sea was on Elf Aquitaine's rig Heimdal in '82. Pace of acceptance increased after the Piper Alpha disaster in '88. By now, there are anything up to 1500 free-fall boats installed on ships and platforms throughout the world, according to free-fall expert Per Brinchmann, development director of one of the leading builders, Omoe SchatHarding, which has produced some 400 of them at Rosendal and Olve in Norway. Brinchmann's belief that the eventual market could be double this suggests that, although it will clearly always remain 'niche', useful volumes of GRP could be involved - especially given the heavy-duty and totally enclosed nature of these craft. As free-fall boats are skid-launched or simply dropped, escaping in one - though happily, this has not had to be done in earnest yet - is like taking part in an extreme sport. Seafarers climb to a deckmounted boarding platform, enter the lifeboat via a large hatch near the craft's stern, clamber down a stepped aisle to the empty seats furthest away from them 0034-3617/01/$ - see front matter © 2001 Elsevier Science Ltd. All rights reserved.
GRP lifesavers meet the challenge
(so that the craft is filled bow first), strap themselves firmly into the padded semireclining seats using a four-point harness and sometimes head restraint as well, and wait. The coxswain boards, closes the hatch firmly against its watertight seal, checks that all occupants are 'installed', straps in and gives the signal for 'go'. Once the restraint link is broken, launching is certain and quick. Whether the craft has been suspended or is inclined pointing down towards the sea on a rail launching system, all then experience a rapid acceleration, a few instants of weightlessness, and then the jarring impact as the boat hits the water at an angle of around 50-60 °. At least the first third of the craft will become submerged, but it quickly resurfaces and the craft makes headway under its own momentum. By the time is has proceeded perhaps 100 m, possibly through blazing oil, the coxswain should have started the small engine so that movement away from the danger area can continue at about 5-6 knots. Even a test launch looks dramatic. To meet the safety of life at sea (SOLAS) regulations of the International Maritime Organization (IMO), every new prototype has to be launched from 1.3 times the certified free-fall height. This meant 47 m for Schat-Harding's latest craft, the FFIO00. During such a test, the lifeboat is fully equipped, and every seat has a 75 kg load of sandbags to simulate a person. Before the prototype stage, there is extensive scale model testing of any new design at the Norwegian Marine Technology Research Institute (MARINTEK) in Trondheim. According to Schat-Harding technical manager R&D Arild Lokoy, "This helps establish critical parameters such as maximum and minimum free-fall heights, maximum water entry angle, headway after water impact, optimum weight condition, optimum mass moment of inertia, and of course acceleration (deceleration) forces. These forces are key when we're calculating the strength the boat will require and in defining the internal seating arrangement." Lokoy's design team also carries out extensive finite element analysis in
calculating hull panel strengths needed to withstand hydrodynamic forces and decelerations of up to 5 g. Nowadays a detailed three-dimensional (3D) model is developed using I-DEAS 3D and twodimensional (2D) drawings are based on this model.
Structure Schat-Harding FFLBs range from a 20person 6.58 m length 4480 kg (gross weight) craft designed for a 12.5 m
free-fall height, to a 60-person 12.57 m long, 16 200 kg (gross) craft designed for a 30 m fall. Structures tend to be coneshaped, with essentially circular cross sections, and fine bow sections for partmg the water at initial entry progressively widening to a voluminous and buoyant stern. Plastics are the material best suited to the construction of these forms, with their complex curvatures. Despite differences in size and shape, all FFLBs in the company's range are constructed December 2001
REINFORCEDplastics
21
GRP lifesavers meet the challenge
similarly. Each comprises a composite hull, canopy and an inner liner. The hull and inner liner are produced by spraying glass fibres, chopped to an inch or two long, with added polyester resin, into female moulds. Spraying with hand-held guns is seen as a quick and cost-effective means of carrying out conventional chopped strand mat (random fibre mat) lay-up, which is subsequently rolled and compressed to expel entrapped air in the usual way. Cure then takes place at room temperature. Admitting that this process does not yield laminates as light and strong as those that could be achieved with hand lay-up of woven fibre mat, Lokoy says that the result is nevertheless both sufficiently strong and economical. He adds, "We employ highly skilled personnel who have full control of laminate thickness, which we verify ultrasonically." While Schat-Harding is reticent over precise details of laminate make-up for commercial reasons, it is known that shell thicknesses in FFLBs generally range from about 3 m m above the main deck to 68 m m in the hull bottom and at points of maximum stress. Highest impact loads are felt not at the bow as might be expected, but under the stern as the high-volume sections there exert their buoyancy.
Projecting items such as the propeller and rudder also experience high stresses, though propellers usually derive some protection from operating in a tunnel or recess moulded into the hull. Bulkheads and longitudinal stringers are added to stiffen the hull. These are based on woven fabrics over Divinycell polyurethane core. The inner liner is bonded in and bolted, and the spaces between the laminates filled with polyurethane foam to provide buoyancy. IMO/SOLAS regulations require positive buoyancy equivalent to 280 N force per person. Most of the available compartments, except the engine space, are foamfilled in this way. Canopies are generally of hand-laminated chopped strand mat (CSM), though fibre mat is used in areas where high stress concentrations are expected. Canopy thicknesses are controlled so that weight and centre of gravity are minimized for stability purposes. Meeting IMO requirements to be able to embark a full complement of survival-suited crew from the mother vessel's deck within three minutes requires a large entrance aperture aft. In Schat-Harding boats, this entrance comprises a composite door seating via a watertight seal onto an aluminium frame. Like their conventional sisters, free-fall
boats are required to have water sprinkler systems that will protect them for eight minutes in a sea of burning kerosene. Lifeboats intended for tankers should also have breathing systems. The small diesel engines used to propel the craft clear once in the water have modified sump and lubrication systems so that they can be started and test-run at the steep angles which are the FFLBs' normal attitude, as well as when they are level. Materials used for the primary structure include Reichold's Norpol PX-4528 isopthalic polyester containing fireretardant aluminium trihydrate, P207 rovings from Vetrotex, Spain; and Isofoam RM120W polyurethane foam from Baxenden Chemical Ltd. Seats comprise contoured polyurethane seat squabs, which provide firm support with controlled yield characteristics, placed into composite seat bases. Seats are shaped and positioned to provide as low a combined acceleration ratio (CAR - the combination of accelerations in all three axes working on the h u m a n body) as possible. The h u m a n frame can tolerate surprisingly high shock loads if these are of short duration. For peak loads of less than a tenth of a second, for instance, the spine can withstand as much as 7 g in line with itself, and 15 g transversely. Deceleration loads are limited to levels at which, assuming that occupants have strapped themselves correctly into the conformal seats, they should survive water entry impact loads without harm.
Similar Other manufacturers tend to use similar material technologies, which are well established in the manufacture of ships' lifeboats throughout the world. Fassmer GmbH of Germany, which has built FFLBs from the mid 1980s, currently produces boats 6 m to 8.5 m long, weighing (empty) 2.6-5.2 tonnes, for cargo ships and tankers. Structures are of fireretardant GRP, all scantlings being to standards approved by Germanischer Lloyd or other national classification societies. Internal mouldings incorporate
22
REINFORCEDplastics December 2001
GRP lifesavers meet the challenge
stowage spaces for drinking water, engine installation and inventory items, though other void spaces are polyurethane foam filled as with the Norwegian-built boats. Features include rearward facing contoured seats with four-point restraint harnesses and a stepped passageway to facilitate rapid boarding. An air space between canopy double mouldings provides a righting m o m e n t should the vessel capsize with any hatches open. (FFLBs are designed to be able to capsize and roll right over should they, by mischance, hit the water sideways or encounter a steep beam sea.) A short platform deck at the stern assists boarding and there is a raised position for the helmsman aft, with a small windowed turret for steering visibility. A Fassmerdesigned rail launching system enables boats to be launched from the stern of a mother ship listing to some 75 °. An FFLB from Norsafe AS set a world record in trials when two of its craft were tested at nearly 50 m height (bow to water surface). This company, which has produced numerous boats of up to 80 passengers capacity and weighing up to 17 tonnes, more normally produces craft for fall heights of 13.5 m for a 6.77 m long, 22-person example to 36 m for its largest lifeboats. The company, which also produces conventional ships' lifeboats, launched its first free-fall boat in 1986. SOLAS-compliant FFLBs produced by Pesbo SA in Spain have the helmsman's position just forward of amidships, its forward face being continuous with the sloping front of the canopy. Three sizes are produced, in standard and fireprotected versions for 23, 32 and 41 occupants. These craft weigh (loaded) 5.19 tonnes for a 7.5 m model, 7.1 tonnes for the intermediate 8.75 m craft and 8.34 tonnes for the largest, 10.35 m lifeboat. Eastern bloc manufacturer Stocznia USTKA SA produces FFLBs of 27 to 59 person capacity, using designs licensed from Robert Hatecke GmbH of Germany. Brodorgradiliste Greben offers 28 to 52 person capacity in seven sizes
ranging from 8.5-14.5 m. They are fleefall certificated for heights of 14 m for the smallest craft to 23 m for the largest. Verhoef Aluminium Scheepsbouw in the Netherlands is out of the general mould (literally) in producing its FFLBs in aluminium. Owners of many working tankers, bulk carriers, RoRo ferries, container ships, other working vessels and offshore installations see that 'hitting the water running' gives a better chance of saving lives should the worst happen, than relying on conventional lifeboats. There is a persuasive case for mandating their use on ships that could sink rapidly, such as bulk carriers and RoRo vessels. In the offshore sector, the ability to surface clear of immediate falling structure or burning oil, proceed another 100 m under m o m e n t u m and then motor away safety, amid burning kerosene if need be, is reassuring. But FFLBs are expensive - up to twice the cost, fully installed, of a conventional ship's boat of equivalent capacity. Against this, by using reliably launchable lifeboats mounted on vessel sterns, owners need install capacity only
equal to the number of persons on board, not double this as has to be the case with conventional lifeboats mounted along ships' sides. Reduced carriage requirements, augmented by reduced maintenance costs of lifesaving equipment, can help nullify the cost disadvantages of flee-fall provision. Reinforced plastics have been one of the key enablers for free-fall lifeboats. Certainly, dropping a traditional ship's wooden lifeboat from a height of 30 m plus would merely have resulted in a loose assemblage of constituent parts, and steel would be too heavy - explaining why the free-fall concept made little real progress before the 1960s when glass reinforced polyester first emerged as a viable boatbuilding material. Relatively low-technology is adequate, since neither lowest possible weight nor osmosis resistance are drivers, so that affordability has been retained. Although GRP FFLBs will probably never be suitable for cruise ships because their use requires training and drills, a future for them seems assured across a range of working vessels and offshore installations. •
December 2001
REINFOR(~Dplastics
23
S
taking to the lifeboats can be a perilous operation. Boats swing, tip on unevenly surged wire cables, fall out of control, hit the ship's sides and sometimes, when the ship is listing, cannot be lowered on one side of the ship at all. (The 50% cut in capacity that could result has had to be allowed for ever since.) In 1976, prompted by several maritime disasters, the Norwegian Ship Research Institute tested an 11 m long boat intended for 'free-fall' launch, by letting it drop 20 m into Hardangar Fjord. A year later, the first manned launch of a free-fall lifeboat took place, from bulk carrier MS Tarcoola at Oresundsavarvet Shipyard.
'Hitting the water running' gives a better chance of saving lives should the worst happen, than relying on conventional lifeboats. The Norwegians had picked up on earlier work daring back to 1897 when AE Falk first patented an enclosed lifeboat capable of sliding off a ship's stern. Prior to World War II Captain White of the Bay and River Navigation Company had proposed the concept of a free-fall lifeboat (he called it a non-sinkable submarine lifeboat). A free-fall craft that clearly resembled a submarine, designed and tested by Dutch yacht builder Joseph 20
RBl~ORC~Dplastics
December 2001
Verhoef, went into service on a ship in 1961. But acceptance of the free-fall concept on any scale really began with the Norwegians' efforts in the '70s. By the early 1980s the new escape system, which could land in the water clear of any close debris or fire, was being installed offshore, the first facility to have it being the DV Delta, while the first use on a fixed installation in the North Sea was on Elf Aquitaine's rig Heimdal in '82. Pace of acceptance increased after the Piper Alpha disaster in '88. By now, there are anything up to 1500 free-fall boats installed on ships and platforms throughout the world, according to free-fall expert Per Brinchmann, development director of one of the leading builders, Omoe SchatHarding, which has produced some 400 of them at Rosendal and Olve in Norway. Brinchmann's belief that the eventual market could be double this suggests that, although it will clearly always remain 'niche', useful volumes of GRP could be involved - especially given the heavy-duty and totally enclosed nature of these craft. As free-fall boats are skid-launched or simply dropped, escaping in one - though happily, this has not had to be done in earnest yet - is like taking part in an extreme sport. Seafarers climb to a deckmounted boarding platform, enter the lifeboat via a large hatch near the craft's stern, clamber down a stepped aisle to the empty seats furthest away from them 0034-3617/01/$ - see front matter © 2001 Elsevier Science Ltd. All rights reserved.
GRP lifesavers meet the challenge
(so that the craft is filled bow first), strap themselves firmly into the padded semireclining seats using a four-point harness and sometimes head restraint as well, and wait. The coxswain boards, closes the hatch firmly against its watertight seal, checks that all occupants are 'installed', straps in and gives the signal for 'go'. Once the restraint link is broken, launching is certain and quick. Whether the craft has been suspended or is inclined pointing down towards the sea on a rail launching system, all then experience a rapid acceleration, a few instants of weightlessness, and then the jarring impact as the boat hits the water at an angle of around 50-60 °. At least the first third of the craft will become submerged, but it quickly resurfaces and the craft makes headway under its own momentum. By the time is has proceeded perhaps 100 m, possibly through blazing oil, the coxswain should have started the small engine so that movement away from the danger area can continue at about 5-6 knots. Even a test launch looks dramatic. To meet the safety of life at sea (SOLAS) regulations of the International Maritime Organization (IMO), every new prototype has to be launched from 1.3 times the certified free-fall height. This meant 47 m for Schat-Harding's latest craft, the FFIO00. During such a test, the lifeboat is fully equipped, and every seat has a 75 kg load of sandbags to simulate a person. Before the prototype stage, there is extensive scale model testing of any new design at the Norwegian Marine Technology Research Institute (MARINTEK) in Trondheim. According to Schat-Harding technical manager R&D Arild Lokoy, "This helps establish critical parameters such as maximum and minimum free-fall heights, maximum water entry angle, headway after water impact, optimum weight condition, optimum mass moment of inertia, and of course acceleration (deceleration) forces. These forces are key when we're calculating the strength the boat will require and in defining the internal seating arrangement." Lokoy's design team also carries out extensive finite element analysis in
calculating hull panel strengths needed to withstand hydrodynamic forces and decelerations of up to 5 g. Nowadays a detailed three-dimensional (3D) model is developed using I-DEAS 3D and twodimensional (2D) drawings are based on this model.
Structure Schat-Harding FFLBs range from a 20person 6.58 m length 4480 kg (gross weight) craft designed for a 12.5 m
free-fall height, to a 60-person 12.57 m long, 16 200 kg (gross) craft designed for a 30 m fall. Structures tend to be coneshaped, with essentially circular cross sections, and fine bow sections for partmg the water at initial entry progressively widening to a voluminous and buoyant stern. Plastics are the material best suited to the construction of these forms, with their complex curvatures. Despite differences in size and shape, all FFLBs in the company's range are constructed December 2001
REINFORCEDplastics
21
GRP lifesavers meet the challenge
similarly. Each comprises a composite hull, canopy and an inner liner. The hull and inner liner are produced by spraying glass fibres, chopped to an inch or two long, with added polyester resin, into female moulds. Spraying with hand-held guns is seen as a quick and cost-effective means of carrying out conventional chopped strand mat (random fibre mat) lay-up, which is subsequently rolled and compressed to expel entrapped air in the usual way. Cure then takes place at room temperature. Admitting that this process does not yield laminates as light and strong as those that could be achieved with hand lay-up of woven fibre mat, Lokoy says that the result is nevertheless both sufficiently strong and economical. He adds, "We employ highly skilled personnel who have full control of laminate thickness, which we verify ultrasonically." While Schat-Harding is reticent over precise details of laminate make-up for commercial reasons, it is known that shell thicknesses in FFLBs generally range from about 3 m m above the main deck to 68 m m in the hull bottom and at points of maximum stress. Highest impact loads are felt not at the bow as might be expected, but under the stern as the high-volume sections there exert their buoyancy.
Projecting items such as the propeller and rudder also experience high stresses, though propellers usually derive some protection from operating in a tunnel or recess moulded into the hull. Bulkheads and longitudinal stringers are added to stiffen the hull. These are based on woven fabrics over Divinycell polyurethane core. The inner liner is bonded in and bolted, and the spaces between the laminates filled with polyurethane foam to provide buoyancy. IMO/SOLAS regulations require positive buoyancy equivalent to 280 N force per person. Most of the available compartments, except the engine space, are foamfilled in this way. Canopies are generally of hand-laminated chopped strand mat (CSM), though fibre mat is used in areas where high stress concentrations are expected. Canopy thicknesses are controlled so that weight and centre of gravity are minimized for stability purposes. Meeting IMO requirements to be able to embark a full complement of survival-suited crew from the mother vessel's deck within three minutes requires a large entrance aperture aft. In Schat-Harding boats, this entrance comprises a composite door seating via a watertight seal onto an aluminium frame. Like their conventional sisters, free-fall
boats are required to have water sprinkler systems that will protect them for eight minutes in a sea of burning kerosene. Lifeboats intended for tankers should also have breathing systems. The small diesel engines used to propel the craft clear once in the water have modified sump and lubrication systems so that they can be started and test-run at the steep angles which are the FFLBs' normal attitude, as well as when they are level. Materials used for the primary structure include Reichold's Norpol PX-4528 isopthalic polyester containing fireretardant aluminium trihydrate, P207 rovings from Vetrotex, Spain; and Isofoam RM120W polyurethane foam from Baxenden Chemical Ltd. Seats comprise contoured polyurethane seat squabs, which provide firm support with controlled yield characteristics, placed into composite seat bases. Seats are shaped and positioned to provide as low a combined acceleration ratio (CAR - the combination of accelerations in all three axes working on the h u m a n body) as possible. The h u m a n frame can tolerate surprisingly high shock loads if these are of short duration. For peak loads of less than a tenth of a second, for instance, the spine can withstand as much as 7 g in line with itself, and 15 g transversely. Deceleration loads are limited to levels at which, assuming that occupants have strapped themselves correctly into the conformal seats, they should survive water entry impact loads without harm.
Similar Other manufacturers tend to use similar material technologies, which are well established in the manufacture of ships' lifeboats throughout the world. Fassmer GmbH of Germany, which has built FFLBs from the mid 1980s, currently produces boats 6 m to 8.5 m long, weighing (empty) 2.6-5.2 tonnes, for cargo ships and tankers. Structures are of fireretardant GRP, all scantlings being to standards approved by Germanischer Lloyd or other national classification societies. Internal mouldings incorporate
22
REINFORCEDplastics December 2001
GRP lifesavers meet the challenge
stowage spaces for drinking water, engine installation and inventory items, though other void spaces are polyurethane foam filled as with the Norwegian-built boats. Features include rearward facing contoured seats with four-point restraint harnesses and a stepped passageway to facilitate rapid boarding. An air space between canopy double mouldings provides a righting m o m e n t should the vessel capsize with any hatches open. (FFLBs are designed to be able to capsize and roll right over should they, by mischance, hit the water sideways or encounter a steep beam sea.) A short platform deck at the stern assists boarding and there is a raised position for the helmsman aft, with a small windowed turret for steering visibility. A Fassmerdesigned rail launching system enables boats to be launched from the stern of a mother ship listing to some 75 °. An FFLB from Norsafe AS set a world record in trials when two of its craft were tested at nearly 50 m height (bow to water surface). This company, which has produced numerous boats of up to 80 passengers capacity and weighing up to 17 tonnes, more normally produces craft for fall heights of 13.5 m for a 6.77 m long, 22-person example to 36 m for its largest lifeboats. The company, which also produces conventional ships' lifeboats, launched its first free-fall boat in 1986. SOLAS-compliant FFLBs produced by Pesbo SA in Spain have the helmsman's position just forward of amidships, its forward face being continuous with the sloping front of the canopy. Three sizes are produced, in standard and fireprotected versions for 23, 32 and 41 occupants. These craft weigh (loaded) 5.19 tonnes for a 7.5 m model, 7.1 tonnes for the intermediate 8.75 m craft and 8.34 tonnes for the largest, 10.35 m lifeboat. Eastern bloc manufacturer Stocznia USTKA SA produces FFLBs of 27 to 59 person capacity, using designs licensed from Robert Hatecke GmbH of Germany. Brodorgradiliste Greben offers 28 to 52 person capacity in seven sizes
ranging from 8.5-14.5 m. They are fleefall certificated for heights of 14 m for the smallest craft to 23 m for the largest. Verhoef Aluminium Scheepsbouw in the Netherlands is out of the general mould (literally) in producing its FFLBs in aluminium. Owners of many working tankers, bulk carriers, RoRo ferries, container ships, other working vessels and offshore installations see that 'hitting the water running' gives a better chance of saving lives should the worst happen, than relying on conventional lifeboats. There is a persuasive case for mandating their use on ships that could sink rapidly, such as bulk carriers and RoRo vessels. In the offshore sector, the ability to surface clear of immediate falling structure or burning oil, proceed another 100 m under m o m e n t u m and then motor away safety, amid burning kerosene if need be, is reassuring. But FFLBs are expensive - up to twice the cost, fully installed, of a conventional ship's boat of equivalent capacity. Against this, by using reliably launchable lifeboats mounted on vessel sterns, owners need install capacity only
equal to the number of persons on board, not double this as has to be the case with conventional lifeboats mounted along ships' sides. Reduced carriage requirements, augmented by reduced maintenance costs of lifesaving equipment, can help nullify the cost disadvantages of flee-fall provision. Reinforced plastics have been one of the key enablers for free-fall lifeboats. Certainly, dropping a traditional ship's wooden lifeboat from a height of 30 m plus would merely have resulted in a loose assemblage of constituent parts, and steel would be too heavy - explaining why the free-fall concept made little real progress before the 1960s when glass reinforced polyester first emerged as a viable boatbuilding material. Relatively low-technology is adequate, since neither lowest possible weight nor osmosis resistance are drivers, so that affordability has been retained. Although GRP FFLBs will probably never be suitable for cruise ships because their use requires training and drills, a future for them seems assured across a range of working vessels and offshore installations. •
December 2001
REINFOR(~Dplastics
23