RULES FOR NEWBUILDINGS Are they good enough

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RULES FOR NEWBUILDINGSAre they good enough?

• Nordic Marine Insurance Day
• 12th June 2007

By Wilhelm Magelssen Sen. Vice President DNV
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Sea transportation - mid 19th century.

• Insurance premiums were high, even up to 20
• And losses were accordingly high
• The phrase safety had a totally different
  meaning

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Development of Classification Rules
Knowledge
?
Risk Based
Computational
Analytical
Empirical
Tabular
1864
1900
1953
1965
1990
Time
2005
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Bad Weather?
Or only fast driving?
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Bad weather?
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Heavy Sea from Port Side
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Now it starts to be heavy Weather
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What about this situation?
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Or this situation?
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Or this?
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Class Rules vs. International Legislation
International Legislation covers aspects related
to Safety, Health and Environment
Accommodation Life saving Navigation Fire Load
Line, Stability Radio Communication Dangerous
goods Security Pollution Prevention Technical
safety (Class certificate) Manning ...
Traditional Classification coverage
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History - Disasters trigger new Rules
Titanic (1912) Torrey Canyon (1967) Amoco Cadiz
(1978) Herald of Free Enterprise (1987) Exxon
Valdez (1989) Scandinavian Star (1990) Bulk
Carriers lost early 1990 Estonia (1994) Erika
(1999) Prestige (2002)
SOLAS (1929) MARPOL (1973) / STCW (1978) SOLAS /
MARPOL 1978 Protocols ISM / SOLAS Ch. II-1 /
FSA OPA 90 / MARPOL SOLAS Ch. II-2 SOLAS Ch. XII
(1997) SOLAS Ch. II-1/Reg. 3-2 Coating of
ballast tanks (1998) SOLAS Ch. II-1 (1995) Erika
Pack I/II -gt EMSA SOLAS Ch. II-1 (2006) SOLAS Ch.
II-1/Reg. 3-2 Stricter requirements to
coating of ballast tanks (2008, 2006 for CSR)
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Focus is mainly on Tank and Bulk

• Tank - for reasons of environmental protection
  Keeping the oil inside
• the hull (Mainly EU driven)
• Bulk -for reasons of Safety Keeping the sea
  water outside the hull (Mainly IMO driven)

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RULE ASSUMPTION

• It is assumed that the ship,machinery
  installations and equipment are to be maintained
  at a standard complying with the requirements of
  the Rules
• It is assumed that the ship,machinery
  installations and equipment are to be adeqately
  manned and competently handled

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DNV Classification of Ships
Fail safe Redundancy
Validate Certificates
DESIGN PHILOSOPHY
Construction Survey Class Certificate
Design Approval
IN-SERVICE SURVEY
Concept safety evaluation
BUILDING INSPECTION
TECHNICAL ANALYSIS
Rules, Regulations and Instructions
RISK ANALYSIS
THREATS FROM ENVIRONMENT ACCIDENTAL LOADS ETC.
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Structural Damage and Deterioration

• In General caused by
• Excessive corrosion
• Design faults
• Bad workmanship
• Fatigue
• Contact, wear and tear
• Navigation in extreme weather conditions

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Hull inspection - where and what to look for
100 SURVEY OF A VLCC WOULD REQUIRE

• Height to climb 11 km
• Area to survey 300 000 m2
• Length of weld 1 200 km
• Length of longitudinals 58 km
• Bottom area 10 700 m2
• 1,0 pitting 85 000 pits

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Summary of CSRs
Publish 15 Jan 2006
30 Sep 2005
Jun 2004
1 Jan 2005
Apr 2005
1 Apr 2006
1 Jan 2006
1st Draft available to Public
2nd Draft available to Public
Industry comments 6 months
Industry comments 5 months
CSR Effective
CSR Adopted
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Feature Net Scantling Approach
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Feature Hull girder ultimate strength

• Harmonised design criteria
• JBP ultimate capacity method is included in the
  JTP Rules

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Harmonization and Maintenance
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Short-term harmonization

• Short-term harmonization issues identified as
  barriers to adoption have been concluded.
• Corrosion additions
• Rounding
• Wave loads (quartering sea, H.G. shear)
• Hull Girder Ultimate Strength
• Buckling (prescriptive buckling)
• Finite element analysis (two methods in JBP)

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Long-term harmonization

• Full harmonization required for
• Wave loads
• Fatigue
• Finite element analysis
• Buckling
• Prescriptive requirements

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CSR Tankers Table of Contents
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CSR Tankers
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CSR Tankers

• Major builder comments which have been
  accommodated
• a) General scantling increase - Feedback received
  that the general scantling increase needs
  justification and is not supported by damage
  records
• Rule change Criteria reviewed and some of the
  allowable stresses for plate and stiffener
  requirements have been increased by 5-7.
• b) Large localised increases from FE buckling -
  2nd draft JTP Rules require some areas where net
  scantlings are significantly above the as-built
  scantlings of present fleet. Typically buckling
  assessment for FE is the cause for the increase.
• Rule change FE procedure revised to take into
  account combined probability of cargo density,
  loading pattern and dynamic load level by
  introducing a correction factor applied on the
  cargo pressure for the extreme dynamic load
  combination.

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CSR Tankers

• Major owner comments which have been
  accommodated
• c) Corrosion margins- corrosion margins are too
  small for a design life of 25 years and will lead
  to a significant amount of steel replacement.
• Rule change upward adjustments made to the
  average and local (pitting, edge and groove)
  corrosion. IACS members agreed to review closely
  whether it is a need and possibility to update
  the margins taking into account all industry
  feedback and service records.
• d) Coating performance standard - lack of a
  minimum performance standard for coating leads to
  large variation in application and actual coating
  life. The coating of some ships is so poor that
  compete renewal by sandblasting and re-coating is
  needed after few years.
• Rule change IACS agreed to include a
  requirement for a minimum performance standard in
  the common structural Rules.
• e) Grinding - allowance for grinding as a measure
  for increasing the fatigue life was questioned.
• Rule change Rules modified to be more specific
  on where credit may be given for grinding.
  Details on what is required in terms of the
  actual grinding.

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CSR Tankers

• Major builder comments which have NOT been
  accommodated
• a) Fatigue - fatigue design standard of 25 year
  operation in North Atlantic wave environment is
  too severe taking into account the typical
  operation of the majority of tankers. The
  criteria in principle disallows designs with
  material of HT36 in deck.
• Reply As the 25 NA design standard is given in
  the draft IMO Goal Based Standard the project has
  decided not to make any amendments to the fatigue
  target.
• b) Hull girder ultimate strength - hull girder
  ULS requirement in the second draft is too severe
  and some existing vessels will not pass even in
  the as-built condition. Use of material of HT36
  is needed for compliance but contradicts the
  fatigue criteria.
• Reply Studies performed during the Rule
  development do not show the same problem.
  Further investigations are being done on the hull
  girder ULS criteria to see if further adjustment
  of the load combination factors are needed.
• c) IACS recommendation 47 Shipbuilding and Repair
  Quality Standard - IACS recommendation is not up
  to date and may cause conflicts with commonly
  used national standards.
• Reply The comment has been forwarded to IACS
  Survey Panel. The Rules have been updated to make
  it clear that acceptable national standards are
  allowed. Rec. 47 is used as common reference
  document for strength assessment (imperfections).

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CSR Tankers

• Major builder comments which have NOT been
  accommodated
• d) Delete primary support member prescriptive
  rules prescriptive requirements for PSM are not
  needed since the members are checked with FEM.
• Reply PMS requirements have been retained to
  have a consistent application of requirements, a
  solid baseline minimum strength level, and to
  catch limitations in the FE analysis such as
  limited quantity of loading cases/conditions and
  assumptions for boundary conditions. To account
  for differences between the two methods, the
  Rules to permit scantlings that are reduced to
  85 of the prescriptive requirements.

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CSR Tankers

• Major owner comments which have NOT been
  accommodated
• e) Rolling tolerances - The under tolerances are
  eating into the wastage allowance and should not
  be accepted. UGS also commented on lack of
  specified procedures/locations for performing
  thickness measurements.
• Reply Question/issue is being forwarded to IACS
  council for review and action.
• f) Approval of national fabrication standards -
  UGS raised concern about approval of national
  fabrication standards on a class by class basis
  without common procedures for the approval of
  such
• Reply The IACS members agreed to forward the
  request to IACS GPG for review and action.
• g) Corrosion Margins some owners wanted
  extremely large corrosion margins built in to the
  CSRs which are even larger than in todays rules.
• Reply The statistical analysis performed by
  IACS did not support such large increases. While
  some increases to the corrosion margins were
  accommodated in the rules, the very large values
  were not.

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Corrosion Margins Oil tankers
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Connection longitudinals and transverse web frames

• More robust web frames
• More robust longitudinals
• Improved end connection areas

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Inner and outer bottom longs

• Improved bottom longitudinals
• Improved inner bottom longitudinals
• Brackets at transverse bhds.

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Hopper web plates

• Possible
• Increase web thickness
• Re-arranged stiffening

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Bracket toes and heels of stringers and webframes

• Flange terminations
• Nice tapering and not too steep angle
• Stringer toe most critical

• Stringer heel
• Normally require back brackets

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Hopper Knuckles

• Change in local design
• Welding details and size
• Increase of plating thickness

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Transverse bulkhead inner bottom connections
Buttress toe connection to inner bottom
Transverse bulkhead stiffener toe connections to
inner bottom
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Transverse bulkhead stiffener toe connection to
main deck longitudinals

• Soft toe type
• Limit in allowable hull girder stress - i.e. AH36
  not fully utilized due to fatigue life.

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Tripping brackets
Tripping bracket connections to trv. bhd.
vertical stiffeners and curved large flanges
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Bilge Keels
Continuous ground bar
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Side longitudinals in the fore peak
Assessment for fatigue aft of the collision
bulkhead, but forward of bulkhead is not covered.
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Webs of primary support members in the fore peak
area

• Higher loads give stricter requirements
• Web frames -thickness
• Breast hooks

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CSR Bulk Carriers
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Main types of bulkcarriers
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Statistics
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Statistics

• Cracks and fractures may be caused by corrosion

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Typical structural damages in cargo area
Cross deck
Topside tank
Side
Transverse bulkhead
Double bottom and hopper tank
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CSR Bulk Carriers Table of Contents
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CSR Bulk Carriers

• 1st hearing (Jun Dec 2004)
• About 3000 comments received during hearing
  period
• 160 from DNV 75 lead to text modifications
• 17 major modifications in the Rules and
  re-writing of Chapters 7(Direct Strength
  Analysis), 8 (Fatigue), 11 (Construction) and 12
  (Ships in Service)
• Modifications issued in 2nd Draft
• 2nd hearing (Apr Sep 2005)
• About 1000 comments received during hearing
  period
• 155 from DNV 75 lead to text modifications
• 16 major modifications in the Rules
• Modifications issued in Final Draft
• Steel weight impact was about 3 to 4 addition
  for 1st Draft, and is 4 to 6 for final draft
  (compared to present designs compliant with UR
  S25)

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Major modifications of bulk carriers rules after
the first draft

• Larger uniform corrosion wastage allowances for
  transverse bulkheads, side shell in line with
  95 probability of non-exceedance (instead of
  90)
• Thickness rounding procedure is modified, due to
  harmonisation between JTP and JBP
• Harmonisation of ships in service requirements
  between JTP and JBP
• Rewritten FEM procedure Finite element models
  are now only three holds models, with modified
  boundary conditions to provide same results
  between direct and superposition methods
• Reduction of the number of loading cases to be
  considered in Direct strength analysis
• Compliance with new SOLAS requirements for
  flooding of DSS bulk carriers
• Quartering sea loading for cross-deck structure,
  further to harmonisation between JTP and JBP
• Mandatory GRAB notation for grab loading and
  steel coil requirements

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CSR Bulk Carriers
Major Industry comments which have been accepted
(page 1)

• Mandatory grab notation In order to protect the
  inner bottom against cargo damages, grab notation
  has been made mandatory (Ship owners comment)
• Increase in values of corrosion additions
  Wastage allowances have been increased by 1 mm to
  2 mm compared to first draft. Higher increases
  concern heated HFO tanks, transverse bulkheads
  and Side shell wind water strake (Ship owners
  comment)
• Modifications of prescriptive requirements in Ch
  3 Sec 6 Ch 9 Sec 1 2 Continuity of strength
  within primary members (from cargo area to engine
  room and fore/aft parts) has been put to the top
  level and the text modified to avoid vague
  expressions (UGS comment). Prescriptive
  requirements concerning spacing of primary
  members have been modified to suit successful
  recent designs (Shipyards comments)
• Prescriptive requirements for bulkheads -
  Prescriptive requirements for transverse
  bulkheads in way of ballast holds of ships
  smaller than 150 m in length have been added
  (Ship owners comments)
• Number of loading conditions for Direct Strength
  Analyses the number of cases to be computed has
  been divided by a factor 2 to consider only the
  cases having practical influence on the design
  (Shipyards comments)
• Buckling procedure the buckling requirements
  have been rewritten to be more explicit and easy
  to apply ( Shipyards comments)

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CSR Bulk Carriers
Major Industry comments which have been accepted
(page 2)

• g) Relative deflection criteria Relative
  deflection criteria between the double bottom and
  the transverse bulkheads has been added to cope
  with UGS concerns about flexible D/B structure
  (Ship owners comment)
• h) Permissible misalignments Values of IACS
  Rec. 47 for permissible misalignments of some
  important structural details have been included
  in the rules as minimum requirements (Ship
  owners comment)
• i) Minimum thickness Minimum thickness of
  weather deck has been found too conservative and
  aligned on Oil Tankers CSR and inner side of DSS
  bulk carriers has been reduced to be not greater
  than side shell (Shipyards comments)
• j) Requirements for pillars - Prescriptive
  requirements for pillars have been added and
  fillet weld accepted in compression only
  (Shipyards comments)
• k) Deep penetration welding The number of
  details where deep penetration welding is
  requested has been increased (Class comments)
• Scantling pressure for hatch covers in ballast
  holds the pressure has been reduced to take
  into account ullage effect ( Manufacturers
  comments)
• Prescriptive coating performance standard Lack
  of requirements in this case may lead to poor
  standards applied in practice (Shipowners
  comment)

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CSR Bulk Carriers
Major Industry comments which have NOT been
accepted

• Provide mandatory prescriptive requirements for
  the spacing/scantlings of all primary members
  Direct strength analysis ( stresses buckling
  deflections) is fundamentally trusted for
  scantlings of primary members in line with modern
  practices (Ship owners comment)
• Request complete ship extent FEM model - results
  of 3 holds models in the cargo area may be
  extrapolated to fore/aft regions (Ship owners
  comments)
• Increases of corrosion allowances not connected
  to IACS statistics partially accepted for areas
  where some damages could be omitted from the
  statistics (voluntary grounding, contact damages
  on side shell) but not in general, as corrosion
  allowances are based on IACS statistics ( Ship
  owners comments)
• Reduce mini thickness of longitudinals
  reducing mini thickness of longitudinals to fit
  present practices was refused due to increase of
  corrosion allowances (Shipyards comments)
• FEM analyses and fatigue procedure lead to
  unreasonable increases of scantlings These
  increases are justified by excessive spacing of
  primary members. FEM analysis is effective to
  detect this problem. Fatigue results are backed
  by real damage cases (Shipyards comments)

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Modifications between the third and final drafts

• Corrosion allowance change limit length is
  returned back to 150 m
• IACS statistics show a difference of corrosion
  between Handymax and Handysize on one side,
  Panamax and Capesize of the other side. The limit
  is 50, 000 dwt, corresponding approximately to
  190 m in length
• While the limit of 190 m is technically
  justified, an additional wastage margin was
  provided in 1st and 2nd drafts, that is better to
  keep
• CSR notation is introduced for vessels complying
  with new Rules
• This will allow easy identification of ships
  built according to the new Common Structural
  Rules for Oil Tankers and Bulk Carriers

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Corrosion Margins Bulk Carriers
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Side frames and longitudinals
Critical areas covered by CSR
Increased safety factor for single side shell
according to Solas XII
Longitudinals in way of the hopper tank at shell,
are most exposed to fatigue cracks. CSR require
25 years operational life in North Atlantic.
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Side frames tohopper tanks
Fatigue check of main frame connection to hopper
sloping plating
Improved steel grade for bracket
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Inner bottom, stool and hopper plate.
Fatigue check of inner bottom plating connection
with lower stool and hopper sloping plating
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Transverse bulkhead and lower stool
Fatigue check of lower stool and corrugated
bulkhead connection
Mandatory strengthening for grab loading
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IACS UR S21 (Rev. 4) for Hatch Covers and Hatch
Coamings
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SOLAS Reg.II-1/3-2 - Protective Coatings

• Motivation
• Coating considered to be a safety issue!
• Valid for protective coatings in
• dedicated seawater ballast tanks - all types of
  ships 500 GRT
• double-side skin spaces of bulk carriers 150 m
  in length

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SOLAS Reg.II-1/3-2 Protective Coatings
Implementation Enter into force dates
Draft PSPC (DE 49)
Adoption of PSPC and revisedSOLAS II-1/3-2
(MSC 82)
Approval of PSPC and SOLAS II-1/3-2 (MSC 81)
SOLAS XII/6.3 enters into force recommending PSPC
for Bulk Carriers
2 12
2 3 4 5 6 7 8 9 10
11 12
2
7 8
2 7 8
2
2007(Jan)
2006(Jan)
2008(Jan)
2009(Jan)
2012(Jan)
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SOLAS reg.II-1/3-2 Now both Newbuilding (PSPC)
Maintenance

• Newbuilding Coating according to PSPC
  (Performance Standard for Protective Coatings)
• Maintenance of coating to be verified by
  Administration based on IMO Guidelines - to be
  developed.
• IACS Rec. No. 87 may be used as basis for
  developing these Guidelines

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IMO PSPC in brief
Target useful life of 15 years

• Sa 2½, sharp edges removed, St 3 on erection
  joint
• 2 x Main coat
• epoxy based, DFT 320 ?m, light color
• On top of shop primer
• zinc based, compatible, intact and clean
• 2 x Stripe coats

• Basic surface preparation
• Basic coating requirements

• Coating system pre-qualified
• Laboratory test or
• Field exposure for min. 5 years GOOD

• IMO minor spot rusting ref.A.744(18)
• IACS PR 34
• spot rusting lt 3 of area under consideration
  no visible failure of coating
• rusting at edges or welds lt 20 of edges or
  welds in area under consideration

• During blasting prior to applying coating
• relative humidity 85
• surface temperature 3C above dew point
• Rust, grease, dust, salt, oil etc. removed
• 50 mg/m2 of Sodium Chloride (NaCl)

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IACS interpretation of PSPC for CSR

• Items of importance in PSPC
• Coating system approval (5)
• Pre-qualification of coating systems
• Inspection Agreement (3.2)
• to be established, also required before PSPC
• Coating Technical File (CTF) (3)
• to be compiled
• Coating inspection (6)
• during coating preparation and application
• Verification (7)

Whom is responsible?
? Coating Manufacturer
? Yard together with Owner/ Coating Manufacturer
? Yard
? Yard
? Class Society
DNV provides a new Class notation to document
compliance with the PSPC

• Refers to the relevant section in the PSPC

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Class involvement for CSR Vessels

• By Whom in Class?
• AE Approval Engineers
• PM Project Managers
• CE Coating Experts

• Where?
• RAC Responsible Approval Centre
• SO Site Office
• CHO Class Head Office
• LO Local Office
• Coating Specification only

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Some consequences of the PSPC

• Administrations/Class
• Implement manage amended regulations
• Prepare instructions guidelines? consistent
  and objective approach needed
• Prepare new Class notations, as needed
• Training of
• Approval engineers Project Managers -
  understand the PSPC
• dedicated staff to NACE/FROSIO, or equivalent

• Shipyards
• Only use pre-qualified coating systems
• Inspection agreement - clarified
• CTF prepared
• Possible upgrading of production system
• Documentation of coating inspectors
  qualifications
• Train/hire qualified coating inspectors
• Increased involvement from Administrations(i.e.
  Class Society for CSR)
• Construction time may increase

• Shipowner
• Maintenance
• recorded in CTF kept onboard
• efficiency of coating - verified by
  Administration
• Better prepared for evaluation by oil companies,
  e.g. Vetting and Rate (A)
• Cost increase - however at same time
• reduced life-cycle costs and better second-hand
  value of vessel!
• ? Increased safety!

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Ships built to the new rules should be at least
as safe and durable as today
CAP 1
THICKNESS
CAP 2
CAP 3
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• In the future we will get
• More and more detailed international regulations
  covering more areas than today
• Environmental regulations will be in focus in the
  immediate future, and we will see a shift from
  local to global regulations (from NOx/SOx to CO2)
• Increased focus on liability for all partners
  within the maritime industry
• Corporate Social Responsibility will play an
  increasing role in shaping the maritime industry

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Thank you for your attendance!