Z10.5

Z10.5
HULL SURVEYS OF DOUBLE SKIN BULK
Z10.5
(Dec.
(cont)CARRIERS
2003)(Corr.1 Jan
2004)(Rev.1
June 2005)(Rev.2
Jan. 2006)(Rev.3
Jan 2006)(Rev.4
June 2006)(Rev.5
Feb 2007)(Rev.6
Apr 2007)(Rev.7
July 2007)(Rev.8
Nov 2007)(Rev.9Mar 2009)(Rev.10
Mar 2011)(Rev.11
July 2011)(Rev.12
May 2012)(Rev.13
June 2013)(Rev.14
Jan 2014)(Rev.15
Feb 2015)(Rev.16
Nov 2016)(Rev.17
Aug 2017)(Rev.18
Jan 2018)(Rev.19
May 2019)(Rev.20
Feb 2023)

1.
1.1
1.2
1.3
1.4

GeneralApplication
Definitions
Repairs
Thickness Measurements And Close-Up Surveys

2.
2.1
2.2
2.3
2.4
2.5
2.6

Special Survey
Schedule
Scope
Extent Of Overall And Close-Up Surveys
Extent Of Thickness Measurements
Extent Of Tank Testing
Additional Special Survey Requirements After Determining Compliance with SOLAS
XII/12 And XII/13

3.
3.1
3.2
3.3

Annual Survey
Schedule
Scope
Additional Annual Survey Requirements After Determining Compliance with SOLAS
XII/12 And XII/13
Examination of double-side skin void spaces for bulk carriers exceeding 20 years ofage and of 150 m in length and upwards

3.4
4.
4.1
4.2

Intermediate Survey
Schedule
Scope

5.
5.1
5.2
5.3
5.4
5.5
5.6
5.7

Preparation For Survey
Survey Programme
Conditions For Survey
Access To Structures
Equipment For Survey
Rescue and emergency response equipment
Survey At Sea Or At Anchorage
Survey Planning Meeting

6.
6.1
6.2
6.3
6.4

Documentation On Board
GeneralSurvey Report FileSupporting Documents
Review Of Documentation On Board

7.
7.1
7.2
7.3
7.4

Procedures For Thickness Measurement
GeneralCertification Of Thickness Measurement Firm
Number and Locations of Measurements
Reporting

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8.
8.1
8.2
8.3
8.4

Acceptance Criteria
General
Acceptance criteria for pitting corrosion of CSR ships
Acceptance criteria for edge corrosion of CSR ships
Acceptance criteria for grooving corrosion of CSR ships

9.
9.1
9.2

Reporting and Evaluation of Survey
Evaluation of Survey Report
Reporting

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ENCLOSURES
Table I:

Minimum Requirements For Close-Up Survey At Special Hull Survey

Table II:

Minimum Requirements For Thickness Measurements At Special Hull Survey Of
Double Skin Bulk Carriers

Table III:

Owners Inspection Report

Table III IV:Requirements For Extent Of Thickness Measurements At Those Areas Of
Substantial Corrosion Of Double Skin Bulk Carriers Within The Cargo Length
Area
Table IV V: Minimum Requirements Of Overall And Close-Up Survey And Thickness
Measurements At Intermediate Survey Of Double Skin Bulk Carriers
Table V VI: Procedures For Certification Of Firms Engaged In Thickness Measurement Of
Hull Structures
Table VI VII:Survey Reporting Principles
Table VII VIII:Executive Hull Summary
Annex I:

Guidelines For Technical Assessment In Conjunction With Planning
For Enhanced Surveys Of Double Skin Bulk Carriers - Special Survey- HullAnnex II:

Recommended Procedures For Thickness Measurements Of Double
Skin Bulk Carriers
IACS Recommended Procedures For Thickness Measurements Of
Double Skin Bulk Carriers Built Under IACS Common Structural Rules

Annex IIIA:

Survey ProgrammeAppendix 1
Appendix 2
Appendix 3

Annex IIIB:

List of Plans
Survey Planning Questionnaire
Other documentation

Survey Planning Questionnaire

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Note:
1.

This Unified Requirement is to be implemented by IACS Members and Associatesfrom 1 January 2005.

2.

Changes introduced in Rev.1 are to be uniformly implemented from 1 July 2006.

3.

Changes introduced in Rev. 2 (para. 1.4, 5.5.4, 5.5.6 and 7.1.3) are to be uniformly
applied by IACS Societies on surveys commenced on or after 1 January 2007.

4.

Changes introduced in Rev. 3 (para. 2.6 and 3.3) are to be uniformly applied by IACS
Societies on surveys commenced on or after 1 January 2007.

5.

Changes introduced in Rev.4 are to be uniformly applied by IACS Societies on
surveys commenced on or after 1 July 2007.

6.

Changes introduced in Rev.5 are to be uniformly implemented for surveys
commenced on or after 1 January 2008, whereas statutory requirements of IMO Res.
MSC 197(80) apply on 1 January 2007.

7.

Changes introduced in Rev.6 are to be uniformly implemented by IACS Societies forsurveys commenced on or after 1 July 2008.

8.

Changes introduced in Rev.7 are to be uniformly applied by IACS Societies on
surveys commenced on or after 1 July 2008.

9.

Changes introduced in Rev.8 are to be uniformly applied by IACS Societies forsurveys commenced on or after the 1 January 2009.

10.

Changes introduced in Rev.9 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 July 2010.
As for the requirements regarding semi-hard coatings, these coatings, if alreadyapplied, will not be accepted from the next special or intermediate survey commenced
on or after 1 July 2010, whichever comes first, with respect to waiving the annualinternal examination of the ballast tanks.

11.

Changes introduced in Rev.10 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 July 2012.

12.

Changes introduced in Rev.11 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 July 2012.

13.

Changes introduced in Rev.12 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 January 2013.

14.

The changes to section 6 introduced in Rev.13 are to be uniformly applied by IACS
Societies for surveys commenced on or after 1 July 2016.
The other changes introduced in Rev.13 are to be uniformly applied by IACS Societies
for surveys commenced on or after 1 July 2014.

15.

Changes introduced in Rev.14 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 January 2015.

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16.

Changes introduced in Rev.15 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 July 2016.

17.

Changes introduced in Rev.16 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 January 2018.

18.

Changes introduced in Rev.17 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 January 2019.

19.

Changes introduced in Rev.18 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 January 2019.

20.

Changes introduced in Rev.19 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 July 2020.

21.

Changes introduced in Rev.20 are to be uniformly applied by IACS Societies forsurveys commenced on or after 1 July 2024.

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1.

GENERAL

1.1

Application

1.1.1 The requirements apply to all self-propelled Double Skin Bulk Carriers.
1.1.2 For bulk carriers with hybrid cargo hold arrangements, e.g. with some cargo holds ofsingle side skin and others of double side skin, the requirements of UR Z10.2 are to apply tocargo holds of single side skin.
1.1.3 The requirements apply to surveys of hull structure and piping systems in way ofcargo holds, cofferdams, pipe tunnels, void spaces, fuel oil tanks within the cargo length area
and all ballast tanks. The requirements are additional to the classification requirements
applicable to the remainder of the ship. Refer to Z7.
1.1.4 The requirements contain the minimum extent of examination, thickness
measurements and tank testing. The survey is to be extended when Substantial Corrosion
and/or structural defects are found and include additional close-up survey when necessary.
1.2

Definitions

1.2.1 Double Skin Bulk Carrier
A Double Skin Bulk Carrier is a ship which is constructed generally with single deck, double
bottom, top-side tanks and hopper side tanks in cargo spaces, and is intended primarily tocarry dry cargo in bulk, including such types as ore carriers and combination carriers1), in
which all cargo holds are bounded by a double-side skin (regardless of the width of the wing
space). Ore and combination carriers are not covered by the IACS Common Structural Rules.
1.2.2 Ballast Tank
A Ballast Tank is a tank which is used solely primarily for salt water ballast, or, whereapplicable, a space which is used for both cargo and salt water ballast will be treated as a
Ballast tank when substantial corrosion has been found in that space. A Double Side Tank is
to be considered as a separate tank even if it is in connection to either the topside tank or thehopper side tank.
1.2.3 Spaces
Spaces are separate compartments including holds, tanks, cofferdams and void spacesbounding cargo holds, decks and the outer hull.
1.2.4 Overall Survey
An Overall Survey is a survey intended to report on the overall condition of the hull structureand determine the extent of additional close-up surveys.
1.2.5 Close-up Survey
A Close-up Survey is a survey where the details of structural components are within the close
visual inspection range of the Surveyor, i.e. normally within reach of hand.
1)

For combination carriers with longitudinal bulkheads additional requirements are specified in UR
Z10.1 or UR Z10.4, as applicable.

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1.2.6 Transverse Section
A Transverse Section includes all longitudinal members such as plating, longitudinals andgirders at the deck, sides, bottom, inner bottom, hopper sides, inner sides top wing innersides and longitudinal bulkheads. For transversely framed vessels, a transverse section
includes adjacent frames and their end connections in way of transverse sections.
1.2.7 Representative Space
Representative Spaces are those which are expected to reflect the condition of other spacesof similar type and service and with similar corrosion prevention systems. When selecting
Representative Spaces account is to be taken of the service and repair history onboard andidentifiable Critical Structural Areas and/or Suspect Areas.
NOTE: Critical Structural Areas are defined in Annex I.
1.2.8 Suspect Area
Suspect Areas are locations showing Substantial Corrosion and/or are considered by thesurveyor to be prone to rapid wastage.
1.2.9 Critical Structural Area
Critical Structural Areas are locations which have been identified from calculations to requiremonitoring or from the service history of the subject ship or from similar or sister ships (ifavailable) to be sensitive to cracking, buckling or corrosion which would impair the structural
integrity of the ship.
1.2.10 Renewal Thickness
Renewal thickness (tren) is the minimum allowable thickness, in mm, below which renewal ofstructural members is to be carried out.
1.2.11 Substantial Corrosion
Substantial Corrosion is an extent of corrosion such that assessment of corrosion patternindicates a wastage in excess of 75% of allowable margins, but within acceptable limits.
For vessels built under the IACS Common Structural Rules, substantial corrosion is an extent
of corrosion such that the assessment of the corrosion pattern indicates a measured
thickness between tren + 0.5mm and tren.
1.2.12 Corrosion Prevention System
A Corrosion Prevention System is normally considered a full hard protective coating.
Hard Protective Coating is usually to be epoxy coating or equivalent. Other coating systems,
which are neither soft nor semi-hard coatings, may be considered acceptable as alternatives
provided that they are applied and maintained in compliance with the manufacturer’s
specifications.

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1.2.13 Coating Condition
Coating condition is defined as follows:• GOOD

condition with only minor spot rusting,• FAIR

condition with local breakdown at edges of stiffeners and weld connections
and/or light rusting over 20% or more of areas under consideration, but lessthan as defined for POOR condition,• POOR

condition with general breakdown of coating over 20% or more, or hardscale at 10% or more, of areas under consideration

1.2.14 Cargo Length Area
Cargo Length Area is that part of the ship which contains cargo holds and adjacent areas
including fuel tanks, cofferdams, ballast tanks and void spaces.
1.2.15 Special Consideration
Special consideration or specially considered (in connection with close-up surveys andthickness measurements) means sufficient close-up inspection and thickness measurements
are to be taken to confirm the actual average condition of the structure under the coating.
1.2.16 Prompt and Thorough Repair
A Prompt and Thorough Repair is a permanent repair completed at the time of survey to thesatisfaction of the Surveyor, therein removing the need for the imposition of any associatedcondition of class.
1.2.17 Pitting Corrosion
Pitting corrosion is defined as scattered corrosion spots/areas with local material reductions
which are greater than the general corrosion in the surrounding area. Pitting intensity isdefined in Figure 1.
1.2.18 Edge Corrosion
Edge corrosion is defined as local corrosion at the free edges of plates, stiffeners, primary
support members and around openings. An example of edge corrosion is shown in Figure 2.
1.2.19 Grooving Corrosion
Grooving corrosion is typically local material loss adjacent to weld joints along abutting
stiffeners and at stiffener or plate butts or seams. An example of groove corrosion is shown in
Figure 3.

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Figure 1 - Pitting intensity diagrams

Figure 2 - Edge corrosion

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Figure 3 - Grooving corrosion
1.3

Repairs

1.3.1 Any damage in association with wastage over the allowable limits (including buckling,
grooving, detachment or fracture), or extensive areas of wastage over the allowable limits,which affects or, in the opinion of the Surveyor, will affect the vessel’s structural,watertight or weathertight integrity, is to be promptly and thoroughly (see 1.2.15) repaired.
Areas to be considered include:- bottom structure and bottom plating- side structure and side plating- deck structure and deck plating- inner bottom structure and inner bottom plating- inner side structure and inner side plating- watertight or oiltight bulkheads- hatch covers and hatch coamings- items in 3.2.3.10.

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Z10.5(cont)For locations where adequate repair facilities are not available, consideration may be given to
allow the vessel to proceed directly to a repair facility. This may require discharging the cargo
and/or temporary repairs for the intended voyage.
1.3.2 Additionally, when a survey results in the identification of structural defects or
corrosion, either of which, in the opinion of the Surveyor, will impair the vessel’s fitness forcontinued service, remedial measures are to be implemented before the ship continues inservice.
1.3.3 Where the damage found on structure mentioned in Para. 1.3.1 is isolated and of a
localised nature which does not affect the ship's structural integrity, consideration may be
given by the surveyor to allow an appropriate temporary repair to restore watertight orweather tight integrity and impose a condition of class in accordance with IACS PR 35, with a
specific time limit.
1.4

Thickness measurements and close-up surveys

In any kind of survey, i.e. special, intermediate, annual or other surveys having the scope ofthe foregoing ones, thickness measurements, when required by Table II, of structures inareas where close-up surveys are required shall be carried out simultaneously with close-up
surveys.

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2.

SPECIAL SURVEY

2.1

Schedule

2.1.1 Special Surveys are to be carried out at 5 years intervals to renew the Classification
Certificate.
2.1.2 The first Special Survey is to be completed within 5 years from the date of the initialclassification survey and thereafter within 5 years from the credited date of the previous
Special Survey. However, an extension of class of 3 months maximum beyond the 5th year
can be granted in exceptional circumstances.
In this case, the next period of class will start from the expiry date of the Special Survey
before the extension was granted.
2.1.3 For surveys completed within 3 months before the expiry date of the Special Survey,
the next period of class will start from the expiry date of the Special Survey. For surveys
completed more than 3 months before the expiry date of the Special Survey, the period ofclass will start from the survey completion date. In cases where the vessel has been laid up
or has been out of service for a considerable period because of a major repair or modificationand the owner elects to only carry out the overdue surveys, the next period of class will startfrom the expiry date of the special survey. If the owner elects to carry out the next due special
survey, the period of class will start from the survey completion date.
2.1.4 The Special Survey may be commenced at the 4th Annual Survey and be progressedwith a view to completion by the 5th anniversary date. When the Special Survey iscommenced prior to the 4th Annual Survey, the entire survey is to be completed within 15
months if such work is to be credited to the Special Survey.
2.1.5 Concurrent crediting to both Intermediate Survey (IS) and Special Survey (SS) for
surveys and thickness measurements of spaces are not acceptable.
2.2

Scope

2.2.1 General
2.2.1.1 The Special Survey is to include, in addition to the requirements of the annual survey,
examination, tests and checks of sufficient extent to ensure that the hull and related piping,
as required in 2.2.1.3, is in a satisfactory condition and is fit for its intended purpose for the
new period of class of 5 years to be assigned, subject to proper maintenance and operationand to periodical surveys being carried out at the due dates.
2.2.1.2 All cargo holds, ballast tanks, including double bottom and double side tanks, pipetunnels, cofferdams and void spaces bounding cargo holds, decks and outer hull are to be
examined, and this examination is to be supplemented by thickness measurement andtesting as required in 2.4 and 2.5, to ensure that the structural integrity remains effective. The
aim of the examination is to discover Substantial Corrosion, significant deformation, fractures,
damages or other structural deterioration, that may be present.
2.2.1.3 All piping systems within the above spaces are to be examined and operationallytested to working pressure to attending Surveyor’s satisfaction to ensure that tightness andcondition remain satisfactory.
Some member Societies use the term "Special Periodical Survey" others use the term "Class Renewal
Survey" instead of the term "Special Survey".

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2.2.1.4 The survey extent of ballast tanks converted to void spaces is to be speciallyconsidered in relation to the requirements for ballast tanks.
2.2.2 Dry Dock Survey
2.2.2.1 A survey in dry dock is to be a part of the Special Survey. The overall and close-up
surveys and thickness measurements, as applicable, of the lower portions of the cargo holds
and ballast tanks are to be carried out in accordance with the applicable requirements forSpecial Surveys, if not already performed.
Note: Lower portions of the cargo holds and ballast tanks are considered to be the parts
below light ballast water line.
2.2.3 Space Protection
2.2.3.1 Where provided, the condition of the corrosion prevention system of ballast tanks is to
be examined. For ballast tanks, excluding double bottom tanks, where a hard protective
coating is found in POOR to be in less than GOOD condition, and it is not renewed, where
soft or semi-hard coating has been applied, or where a hard protective coating has not been
applied from the time of construction, the tanks in question are to be examined at annualintervals. Thickness measurements are to be carried out as deemed necessary by theSurveyor.
When such a breakdown of hard protective coating is found in water ballast double bottom
tanks and it is not renewed, where a soft or semi-hard coating is applied, or where a hardProtective Coating has not been applied from the time of construction, the tanks in question
may be examined at annual intervals. When considered necessary by the Surveyor, or where
extensive corrosion exists, thickness measurements are to be carried out.
2.2.3.2 Where a hard protective coating is provided in cargo holds, as defined by Z9 and isfound in GOOD condition, the extent of close-up surveys and thickness measurements may
be specially considered.
2.2.3.3 For double-side skin void spaces bounding cargo holds for bulk carriers exceeding 20
years of age and of 150 m in length and upwards, where provided, the condition of thecorrosion prevention system of void spaces shall be examined. Where a hard protective
coating is found to be in POOR condition, and it is not renewed, or where a soft or semi-hardcoating has been applied, or where a hard protective coating has not been applied from thetime of construction, the void spaces in question shall be examined at annual intervals.
Thickness measurements shall be carried out as deemed necessary by the surveyor.
2.2.4 Hatch Covers and Coamings
The hatch covers and coamings are to be surveyed as follows:
2.2.4.1 A thorough inspection of the items listed in 3.2.3 is to be carried out, in addition to all
hatch covers and coamings.

1

Subject to cargo hold hatch covers of approved design which structurally have noaccess to the internals, close-up survey/thickness measurement shall be done ofaccessible parts of hatch covers structures.

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2.2.4.2 Checking of the satisfactory operation of all mechanically operated hatch covers is to
be made, including:• stowage and securing in open condition;• proper fit and efficiency of sealing in closed condition;• operational testing of hydraulic and power components, wires, chains, and link
drives.
2.2.4.3 Checking the effectiveness of sealing arrangements of all hatch covers by hosetesting or equivalent.
2.2.4.4 Close-up survey and thickness measurement1 of the hatch cover and coaming plating
and stiffeners is to be carried out as given in Table I and Table II.
2.3

Extent of Overall and Close-up Surveys

2.3.1 An overall survey of all tanks and spaces is to be carried out at each Special Survey.
Fuel oil tanks in the cargo length area are to be surveyed as follows:
Special Survey
No.1
Age ≤ 5Special Survey
No.2
5 < Age ≤ 10

Special Survey
No.3
10 < Age ≤ 15

None

One

Two

Special Survey
No.4
and Subsequent
15 < AgeHalf, minimum two

Notes
1. These requirements apply to tanks of integral (structural) type.
2. If a selection of tanks is accepted to be examined, then different tanks are to be examinedat each special survey, on a rotational basis.
3. Peak tanks (all uses) are subject to internal examination at each special survey.
4. At special survey No.3 and subsequent special surveys, one deep tank for fuel oil in the
cargo area is to be included, if fitted.
2.3.2 The minimum requirements for close-up surveys at Special Surveys are given in
Table I/Sheet 1 for double skin bulk carriers, excluding ore carriers and in Table I/Sheet 2 forore carriers, respectively.
2.3.3 The Surveyor may extend the close-up survey as deemed necessary taking into
account the maintenance of the spaces under survey, the condition of the corrosion
prevention system and where spaces have structural arrangements or details which havesuffered defects in similar spaces or on similar ships according to available information.
2.3.4 For areas in spaces where hard protective coatings are found to be in a GOOD
condition, the extent of close-up surveys according to Table I may be specially considered,refer also to 2.2.3.2.
2.4

Extent of Thickness Measurements

2.4.1 The minimum requirements for thickness measurements at Special Surveys are given
in Table II.

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2.4.2 Provisions for extended measurements for areas with Substantial Corrosion are given
in Table III IV and as may be additionally specified in the Survey Programme as required by
5.1. These extended thickness measurements are to be carried out before the survey iscredited as completed. Suspect Areas identified at previous surveys are to be examined.
Areas of substantial corrosion identified at previous surveys are to have thickness
measurements taken.
For vessels built under IACS Common Structural Rules, the identified substantial corrosion
areas may be:a) protected by coating applied in accordance with the coating manufacturer’s requirements
and examined at annual intervals to confirm the coating in way is still in good condition, or
alternativelyb) required to be measured at annual intervals.
2.4.3 The Surveyor may further extend the thickness measurements as deemed necessary.
2.4.4 For areas in tanks where hard protective coatings are found to be in a GOOD
condition, the extent of thickness measurements according to Table II may be speciallyconsidered. Refer also to 2.2.3.2.
2.4.5 Transverse sections are to be chosen where the largest reductions are suspected tooccur or are revealed from deck plating measurements, one of which is to be in the amidships
area.
2.4.6 Representative thickness measurement to determine both general and local levels ofcorrosion in the transverse web frames in all water ballast tanks is to be carried out.
Thickness measurement is also to be carried out to determine the corrosion levels on thetransverse bulkhead plating. The extent of thickness measurements may be speciallyconsidered provided the surveyor is satisfied by the close-up survey, that there is no
structural diminution, and the hard protective coating where applied remains efficient.
2.5

Extent of Tank Testing

2.5.1 All boundaries of water ballast tanks, deep tanks and cargo holds used for waterballast within the cargo length area are to be pressure tested. For Fuel Oil Tanks, only
representative tanks are to be pressure tested.
2.5.2 The Surveyor may extend the tank testing as deemed necessary.
2.5.3 Boundaries of ballast tanks are to be tested with a head of liquid to the top of air pipes.
2.5.4 Boundaries of ballast holds are to be tested with a head of liquid to near to the top of
hatches.
2.5.5 Boundaries of fuel oil tanks are to be tested with a head of liquid to the highest pointthat liquid will rise under service conditions. Tank testing of fuel oil tanks may be speciallyconsidered based on a satisfactory external examination of the tank boundaries, and aconfirmation from the Master stating that the pressure testing has been carried out according
to the requirements with satisfactory results.
2.5.6 The testing of double bottom tanks and other spaces not designed for the carriage ofliquid may be omitted, provided a satisfactory internal examination together with an
examination of the tanktop is carried out.
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2.6
Additional special survey requirements after determining compliance withSOLAS XII/12 and XII/13
2.6.1 For ships complying with the requirements of SOLAS XII/12 for hold, ballast and dry
space water level detectors, the special survey is to include an examination and a test of thewater ingress detection systems and of their alarms.
2.6.2 For ships complying with the requirements of SOLAS XII/13 for the availability ofpumping systems, the special survey is to include an examination and a test of the means fordraining and pumping ballast tanks forward of the collision bulkhead and bilges of dry spaces
any part of which extends forward of the foremost cargo hold, and of their controls.

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3.

ANNUAL SURVEY

3.1

Schedule

3.1.1 Annual Surveys are to be held within 3 months before or after the anniversary datefrom the date of the initial classification survey or of the date credited for the last Special
Survey.
3.2

Scope

3.2.1 General
3.2.1.1 The survey is to consist of an examination for the purpose of ensuring, as far aspracticable, that the hull, weather decks, hatch covers, coamings and piping are maintainedin a satisfactory condition and should take into account the service history, condition andextent of the corrosion prevention system of ballast tanks and areas identified in the survey
report file.
3.2.2 Examination of the hull
3.2.2.1 Examination of the hull plating and its closing appliances as far as can be seen.
3.2.2.2 Examination of watertight penetrations as far as practicable.
3.2.3 Examination of weather decks, hatch covers and coamings
3.2.3.1 Confirmation is to be obtained that no unapproved changes have been made to thehatch covers, hatch coamings and their securing and sealing devices since the last survey.
3.2.3.2 A thorough survey of cargo hatch covers and coamings is only possible byexamination in the open as well as closed positions and is to include verification of proper
opening and closing operation. As a result, the hatch cover sets within the forward 25% of
the ship’s length and at least one additional set, such that all sets on the ship are assessed atleast once in every 5-year period, are to be surveyed open, closed and in operation to the full
extent on each direction at each annual survey, including:.1 stowage and securing in open condition;.2 proper fit and efficiency of sealing in closed condition; and.3 operational testing of hydraulic and power components, wires, chains, and link
drives.
The closing of the covers is to include the fastening of all peripheral, and cross joint cleats orother securing devices. Particular attention is to be paid to the condition of the hatch covers
in the forward 25% of the ship’s length, where sea loads are normally greatest.
3.2.3.3 If there are indications of difficulty in operating and securing hatch covers, additional
sets above those required by 3.2.3.2, at the discretion of the surveyor, are to be tested inoperation.
3.2.3.4 Where the cargo hatch securing system does not function properly, repairs are to be
carried out under the supervision of the Classification Society. Where hatch covers or
coamings undergo substantial repairs, the strength of securing devices should be upgradedto comply with S21.5 of UR S21.

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3.2.3.5 For each cargo hatch cover set, at each annual survey, the following items are to be
surveyed:
1. Cover panels, including side plates, and stiffener attachments that may beaccessible in the open position by close-up survey (for corrosion, cracks,
deformation);
2. sealing arrangements of perimeter and cross joints (gaskets for condition andpermanent deformation, flexible seals on combination carriers, gasket lips,
compression bars, drainage channels and non return valves);
3. clamping devices, retaining bars, cleating (for wastage, adjustment, and conditionof rubber components);
4. closed cover locating devices (for distortion and attachment);
5. chain or rope pulleys;
6. guides;
7. guide rails and track wheels;
8. stoppers;
9. wires, chains, tensioners, and gypsies;
10. hydraulic system, electrical safety devices and interlocks; and11. end and interpanel hinges, pins and stools where fitted.
3.2.3.6 At each hatchway, at each annual survey, the coamings, with plating, stiffeners andbrackets are to be checked for corrosion, cracks and deformation, especially of the coaming
tops, including close-up survey.
3.2.3.7 Where considered necessary, the effectiveness of sealing arrangements may be
proved by hose or chalk testing supplemented by dimensional measurements of seal
compressing components.
3.2.3.8 Where portable covers, wooden or steel pontoons are fitted, checking the satisfactory
condition, where applicable, of:-wooden covers and portable beams, carriers or sockets for the portable beam, andtheir securing devices;
steel pontoons, including close-up survey of hatchcover plating;tarpaulins;
cleats, battens and wedges;
hatch securing bars and their securing devices;loading pads/bars and the side plate edge;
guide plates and chocks;
compression bars, drainage channels and drain pipes (if any).

3.2.3.9 Examination of flame screens on vents to all bunker tanks.
3.2.3.10 Examination of bunker and vent piping systems, including ventilators.

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3.2.4 Examination of Cargo Holds.
3.2.4.1 Double Skin Bulk Carriers 10-15 years of age. The following is to apply:a)Overall survey of two selected cargo holds.

b)When considered necessary by the Surveyor, or where extensive corrosion exists,
thickness measurement is to be carried out. If the results of these thickness
measurements indicate that Substantial Corrosion is found, the extent of thickness
measurements is to be increased in accordance with Table III IV. These extended
thickness measurements are to be carried out before the annual survey iscredited ascomplete. Suspect Areas identified at previous surveys are to be examined.
Areas of substantial corrosion identified at previous surveys are to have thickness
measurements taken.
For vessels built under the IACS Common Structural Rules, the annual thickness
gauging may be omitted where a protective coating has been applied in accordancewith the coating manufacturer’s requirements and is maintained in good condition.
c)

All piping and penetrations in cargo holds, including overboard piping, are to be
examined.

3.2.4.2 Double Skin Bulk Carriers over 15 years of age. The following is to apply:a)Overall survey of all cargo holds.

b)When considered necessary by the Surveyor, or where extensive corrosion exists,
thickness measurement is to be carried out. If the results of these thickness
measurements indicate that Substantial Corrosion is found, the extent of thickness
measurements is to be increased in accordance with Table III IV. These extended
thickness measurements are to be carried out before the annual survey iscredited as
com plete. Suspect Areas identified at previous surveys are to be examined.
Areas of substantial corrosion identified at previous surveys are to have thickness
measurements taken.
For vessels built under the IACS Common Structural Rules, the annual thickness
gauging may be omitted where a protective coating has been applied in accordancewith the coating manufacturer’s requirements and is maintained in good condition.
c)

All piping and penetrations in cargo holds, including overboard piping, are to be
examined.

3.2.5 Examination of Ballast Tanks
3.2.5.1 Examination of Ballast Tanks when required as a consequence of the results of theSpecial Survey and Intermediate Survey is to be carried out. When considered necessary by
the surveyor, or where extensive corrosion exists, thickness measurements are to be carriedout. If the results of these thickness measurements indicate that Substantial Corrosion isfound, the extent of thickness measurements is to be increased in accordance with Table III
IV. These extended thickness measurements are to be carried out before the survey iscredited as complete.
Suspect Areas identified at previous surveys are to be examined. Areas of substantial
corrosion identified at previous surveys are to have thickness measurements taken.
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Z10.5(cont)For vessels built under the IACS Common Structural Rules, the annual thickness gauging
may be omitted where a protective coating has been applied in accordance with the coating
manufacturer’s requirements and is maintained in good condition.
3.3
Additional annual survey requirements after determining compliance withSOLAS XII/12 and XII/13
3.3.1 For ships complying with the requirements of SOLAS XII/12 for hold, ballast and dry
space water level detectors, the annual survey is to include an examination and a test, at
random, of the water ingress detection systems and of their alarms.
3.3.2 For ships complying with the requirements of SOLAS XII/13 for the availability ofpumping systems, the annual survey is to include an examination and a test, of the means fordraining and pumping ballast tanks forward of the collision bulkhead and bilges of dry spaces
any part of which extends forward of the foremost cargo hold, and of their controls.
3.4
Examination of double-side skin void spaces for bulk carriers exceeding 20
years of age and of 150 m in length and upwards
Examination of double-side skin void spaces, for bulk carriers exceeding 20 years of age andof 150 m in length and upwards, are to be carried out when required as a consequence of theresults of the renewal survey (as required by para 2.2.3.3) and intermediate survey (asrequired by 4.2.4.1). When considered necessary by the Administration, or when extensive
corrosion exists, thickness measurements should be carried out. If the results of thesethickness measurements indicate that substantial corrosion is found, the extent of thickness
measurements should be increased in accordance with table IV. These extended thickness
measurements should be carried out before the survey is credited as completed. Suspectareas identified at previous surveys should be examined. Areas of substantial corrosion
identified at previous surveys should have thickness measurements taken.
For bulk carriers built under the IACS Common Structural Rules, the annual thickness
gauging may be omitted where a protective coating has been applied in accordance with thecoating manufacturer's requirements and is maintained in good condition.

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4.

INTERMEDIATE SURVEY

4.1

Schedule

4.1.1 The Intermediate Survey is to be held at or between either the 2nd or 3rd Annual
Survey.
4.1.2 Those items, which are additional to the requirements of the Annual Survey, may besurveyed either at or between the 2nd and 3rd Annual Survey.
4.1.3 Concurrent crediting to both Intermediate Survey (IS) and Special Survey (SS) for
surveys and thickness measurements of spaces are not acceptable.
4.2

Scope

4.2.1 General
4.2.1.1 The survey extent is dependent on the age of the vessel as specified in 4.2.2 to 4.2.4
and shown in Table IV V.
4.2.2 Double Skin Bulk Carriers 5 - 10 years of age. The following is to apply:
4.2.2.1 Ballast Tanksa)

For tanks used for water ballast, an overall survey of representative tanks selectedby the Surveyor is to be carried out. The selection is to include fore and aft peaktanks and a number of other tanks, taking into account the total number and typeof ballast tanks. If such overall survey reveals no visible structural defects, theexamination may be limited to verification that the corrosion prevention systemremains efficient.

b)

Where POOR coating a hard coating is found to be in less than GOOD condition,
corrosion or other defects are found in water Ballast tanks or where a hard Protective
Coating was not applied from the time of construction, the examination is to beextended to other Ballast tanks of the same type.

c)

In ballast tanks other than double bottom tanks, where a hard Protective Coating isfound in POOR to be in less than GOOD condition, and it is not renewed, or where
soft or semi-hard coating has been applied, or where a hard protective coating was
not applied from the time of construction, the tanks in question are to be examined
and thickness measurements carried out as considered necessary at annual intervals.
When such breakdown of hard protective coating is found in ballast double bottom
tanks, or where a soft or semi-hard coating has been applied, or where a hardprotective coating has not been applied, the tanks in question may be examined atannual intervals. When considered necessary by the Surveyor, or where extensive
corrosion exists, thickness measurements are to be carried out.

d)In addition to the requirements above, suspect areas identified at previous surveys
are to be overall and close-up surveyed.

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4.2.2.2 Cargo Holdsa)

An overall survey of all cargo holds is to be carried out.

b)

Where considered necessary by the Surveyor as a result of the overall survey as
described in 4.2.2.2a, the survey is to be extended to include a close-up survey ofthose areas of structure in the cargo holds selected by the Surveyor.

4.2.2.3 Extent of Thickness Measurementsa)Thickness measurements are to be carried out to an extent sufficient to determine
both general and local corrosion levels at areas subject to close-up survey, whererequired as per 4.2.2.2b), and as provided in 4.2.2.1c).

b)

The extent of thickness measurement may be specially considered provided theSurveyor is satisfied by the close-up survey that there is no structural diminution
and the hard protective coatings are found to be in a GOOD condition.

c)

Where Substantial Corrosion is found, the extent of thickness measurements is to
be increased in accordance with the requirements of Table IV. These extended
thickness measurements are to be carried out before the survey is credited ascompleted. Suspect Areas identified at previous surveys are to be examined.
Areas of substantial corrosion identified at previous surveys are to have thickness
measurements taken.
For vessels built under IACS Common Structural Rules, the identified substantial
corrosion areas may be:a) protected by coating applied in accordance with the coating manufacturer’s
requirements and examined at annual intervals to confirm the coating in way is still ingood condition, or alternativelyb) required to be measured at annual intervals.

d)Where the hard protective coating in cargo holds, as defined by Z9 is found to be in
GOOD condition, the extent of close-up surveys and thickness measurements may be
specially considered.

Explanatory note:
For existing bulk carriers, where owners may elect to coat or recoat cargo holds as noted
above, consideration may be given to the extent of the close-up and thickness measurement
surveys. Prior to the coating of cargo holds of existing ships, scantlings are to be ascertainedin the presence of a surveyor.
4.2.3 Double Skin Bulk Carriers 10 – 15 years of age. The following is to apply:
4.2.3.1 The requirements of the Intermediate Survey are to the same extent as the previous
Special Survey as required in 2 and 5.1. However, internal examination of fuel oil tanks andpressure testing of all tanks are not required unless deemed necessary by the attending
Surveyor.
4.2.3.2 In application of 4.2.3.1, the intermediate survey may be commenced at the second
annual survey and be progressed during the succeeding year with a view to completion at thethird annual survey in lieu of the application of 2.1.4.

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4.2.3.3 In application of 4.2.3.1, an under water survey may be considered in lieu of therequirement of 2.2.2.
4.2.4 Double Skin Bulk Carriers over 15 years of age. The following is to apply:
4.2.4.1 The requirements of the Intermediate Survey are to be to the same extent as theprevious Special Survey as required in 2 and 5.1.
However, internal examination of fuel oil tanks and pressure testing of all tanks are notrequired unless deemed necessary by the attending Surveyor.
4.2.4.2 In application of 4.2.4.1, the intermediate survey may be commenced at the second
Annual Survey and be progressed during the succeeding year with a view to completion at
the third Annual Survey in lieu of the application of 2.1.4.
4.2.4.3 In application of 4.2.4.1, a survey in dry dock is to be part of the Intermediate Survey.
The overall and close-up surveys and thickness measurements, as applicable, of the lower
portions of the cargo holds and ballast tanks are to be carried out in accordance with theapplicable requirements for Intermediate Surveys, if not already performed.
Note: Lower portions of the cargo holds and ballast tanks are considered to be the parts
below light ballast water line.

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5.

PREPARATION FOR SURVEY

5.1

Survey Programme

5.1.1 The Owner in co-operation with the Classification Society is to work out a specificSurvey Programme prior to the commencement of any part of:•

the Special Survey•

the Intermediate Survey for double skin bulk carriers over 10 years of age.

The Survey Programme is to be in a written format based on the information in Annex IIIA.
The survey is not to commence until the Survey programme has been agreed.
5.1.1.1 Prior to the development of the survey programme, the survey planning questionnaire
is to be completed by the owner based on the information set out in Annex IIIB, andforwarded to the Classification Society.
5.1.1.2 The Survey Programme at Intermediate Survey may consist of the Survey
Programme at the previous Special Survey supplemented by the Executive Hull Summary ofthat Special Survey and later relevant survey reports.
The Survey Programme is to be worked out taking into account any amendments to thesurvey requirements implemented after the last Special Survey carried out.
5.1.2 In developing the Survey Programme, the following documentation is to be collected
and consulted with a view to selecting holds, tanks, areas, and structural elements to be
examined:• survey status and basic ship information,• documentation on-board, as described in 6.2 and 6.3,
• main structural plans (scantlings drawings), including information regarding useof high tensile steels (HTS),• relevant previous survey and inspection reports from both Classification Society
and the Owner,• information regarding the use of the ship’s holds and tanks, typical cargoes andother relevant data,• information regarding corrosion prevention level on the new-building,• information regarding the relevant maintenance level during operation.
5.1.3 The submitted Survey Programme is to account for and comply, as a minimum, withthe requirements of Tables I and II and paragraph 2.5 for close-up survey, thickness
measurement and tank testing, respectively, and is to include relevant information including
at least:• basic ship information and particulars,• main structural plans (scantling drawings), including information regarding use ofhigh tensile steels (HTS),
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Z10.5• plan of holds and tanks,

Z10.5• list of holds and tanks with information on use, protection and condition of
coating,(cont)• conditions for survey (e.g., information regarding hold and tank cleaning, gas
freeing, ventilation, lighting, etc.),• provisions and methods for access to structures,• equipment for surveys,• nomination of holds and tanks and areas for close-up survey (per 2.3),• nominations of sections and areas for thickness measurement (per 2.4),• nomination of tanks for tank testing (per 2.5),• damage experience related to the ship in question.
5.1.4 The Classification Society will advise the Owner of the maximum acceptable structural
corrosion diminution levels applicable to the vessel.
5.1.5 Use may also be made of the Guidelines for Technical Assessment in Conjunction
with Planning for Enhanced Surveys of Double Skin Bulk Carriers - Special Survey - Hull,contained in Annex I. These guidelines are a recommended tool which may be invoked at thediscretion of the Classification Society, when considered necessary and appropriate, in
conjunction with the preparation of the required Survey Programme.
5.2

Conditions for survey

5.2.1 The Owner is to provide the necessary facilities for a safe execution of the survey.
5.2.1.1 In order to enable the attending surveyors to carry out the survey, provisions forproper and safe access, are to be agreed between the owner and the Classification society
are to be in accordance with IACS PR 37.
5.2.1.2 Details of the means of access are to be provided in the survey planningquestionnaire.
5.2.1.3 In cases where the provisions of safety and required access are judged by theattending surveyor(s) not to be adequate, the survey of the spaces involved is not to proceed.
5.2.2 Cargo holds, tanks and spaces are to be safe for access. Cargo holds, tanks andspaces are to be gas free and properly ventilated. Prior to entering a tank, void or enclosed
space, it is to be verified that the atmosphere in the tank is free from hazardous gas andcontains sufficient oxygen.
5.2.3 In preparation for survey and thickness measurements and to allow for a thoroughexamination, all spaces are to be cleaned including removal from surfaces of all loose
accumulated corrosion scale. Spaces are to be sufficiently clean and free from water, scale,dirt, oil residues etc. to reveal corrosion, deformation, fractures, damages, or other structural
deterioration as well as the condition of the coating. However, those areas of structure whose
renewal has already been decided by the owner need only be cleaned and descaled to theextent necessary to determine the limits of the areas to be renewed.
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5.2.4 Sufficient illumination is to be provided to reveal corrosion, deformation, fractures,
damages or other structural deterioration as well as the condition of the coating.
5.2.5 Where Soft or Semi-hard Coatings have been applied, safe access is to be provided
for the Surveyor to verify the effectiveness of the coating and to carry out an assessment of
the conditions of internal structures which may include spot removal of the coating. Whensafe access cannot be provided, the soft or semi-hard coating is to be removed.
5.3

Access to structures

5.3.1 For overall surveys, means are to be provided to enable the Surveyor to examine thehull structure in a safe and practical way.
5.3.2 For close-up surveys, one or more of the following means for access, acceptable to
the Surveyor, is to be provided:

5.4•

permanent staging and passages through structures,•

temporary staging, e.g. ladders and passages through structures,•

hydraulic arm vehicles such as conventional cherry pickers, lifts and movable
platforms,•

portable ladders,•boats or rafts,•

other equivalent means.

Equipment for survey

5.4.1 Thickness measurement is normally to be carried out by means of ultrasonic test
equipment. The accuracy of the equipment is to be proven to the Surveyor as required.
5.4.2 One or more of the following fracture detection procedures may be required if deemednecessary by the Surveyor:• radiographic equipment,• ultrasonic equipment,• magnetic particle equipment,• dye penetrant.
5.4.3 Explosimeter, oxygen-meter, breathing apparatus, lifelines, riding belts with rope andhook and whistles together with instructions and guidance on their use are to be madeavailable during the survey. A safety check-list is to be provided.
5.4.4 Adequate and safe lighting is to be provided for the safe and efficient conduct of thesurvey.
5.4.5 Adequate protective clothing is to be made available and used (e.g. safety helmet,
gloves, safety shoes, etc.) during the survey.
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5.5

Rescue and emergency response equipment

If breathing apparatus and/or other equipment is used as ‘Rescue and emergency response
equipment’ then it is recommended that the equipment should be suitable for theconfiguration of the space being surveyed.
5.6

Survey at sea or at anchorage

5.6.1 Survey at sea or at anchorage may be accepted provided the Surveyor is given thenecessary assistance from the personnel onboard. Necessary precautions and proceduresfor carrying out the survey are to be in accordance with 5.1, 5.2, 5.3 and 5.4.
5.6.2 A communication system is to be arranged between the survey party in the spaces
under examination and the responsible officer on deck. This system is to also include thepersonnel in charge of ballast pump handling if boats or rafts are used.
5.6.3 Surveys of tanks or applicable holds by means of boats or rafts may only beundertaken with the agreement of the Surveyor, who is to take into account the safety
arrangements provided, including weather forecasting and ship response under foreseeableconditions and provided the expected rise of water within the tank does not exceed 0.25m.
5.6.4 When rafts or boats will be used for close-up survey the following conditions are to beobserved:.1

only rough duty, inflatable rafts or boats, having satisfactory residual buoyancy
and stability even if one chamber is ruptured, are to be used;.2

the boat or raft is to be tethered to the access ladder and an additional person
is to be stationed down the access ladder with a clear view of the boat or raft;.3

appropriate lifejackets are to be available for all participants;.4

the surface of water in the tank or hold is to be calm (under all foreseeableconditions the expected rise of water within the tank is not to exceed 0.25 m)
and the water level stationary. On no account is the level of the water to berising while the boat or raft is in use;.5

the tank, hold or space must contain clean ballast water only. Even a thinsheen of oil on the water is not acceptable; and.6

at no time is the water level to be allowed to be within 1 m of the deepest
under deck web face flat so that the survey team is not isolated from a direct
escape route to the tank hatch. Filling to levels above the deck transverses isonly to be contemplated if a deck access manhole is fitted and open in the bay
being examined, so that an escape route for the survey party is available at all
times. Other effective means of escape to the deck may be considered.

5.6.5 Rafts or boats alone may be allowed for inspection of the under deck areas for tanks
or spaces, if the depth of the webs is 1.5 m or less.
5.6.6 If the depth of the webs is more than 1.5 m, rafts or boats alone may be allowed only:.1 when the coating of the under deck structure is in GOOD condition and there isno evidence of wastage; orPage 27 of 127

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if a permanent means of access is provided in each bay to allow safe entry andexit. This means:i.

access direct from the deck via a vertical ladder and a small platform
fitted approximately 2 m below the deck in each bay; orii.

access to deck from a longitudinal permanent platform having ladders to
deck in each end of the tank. The platform shall, for the full length of thetank, be arranged in level with, or above, the maximum water levelneeded for rafting of under deck structure. For this purpose, the ullage
corresponding to the maximum water level is to be assumed not morethan 3m from the deck plate measured at
the midspan of decktransverses and in the middle length of the tank.

If neither of the above conditions are met, then staging or an “other equivalent means”
is to be provided for the survey of the under deck areas.
5.6.7 The use of rafts or boats alone in paragraphs 5.6.5 and 5.6.6 does not preclude theuse of boats or rafts to move about within a tank during a survey.
Reference is made to IACS Recommendation 39 - Guidelines for the use of Boats or Rafts for
Close-up surveys.
5.7

Survey Planning Meeting

5.7.1 The establishment of proper preparation and the close co-operation between theattending surveyor(s) and the owner’s representatives onboard prior to and during the survey
are an essential part in the safe and efficient conduct of the survey. During the survey onboard safety meetings are to be held regularly.
5.7.2 Prior to commencement of any part of the renewal and intermediate survey, a survey
planning meeting is to be held between the attending surveyor(s), the owner’s representativein attendance, the TM firm representative, where involved, and the master of the ship or an
appropriately qualified representative appointed by the master or Company for the purpose toascertain that all the arrangements envisaged in the survey programme are in place, so as toensure the safe and efficient conduct of the survey work to be carried out. See also 7.1.2.
5.7.3 The following is an indicative list of items that are to be addressed in the meeting:.1

schedule of the vessel (i.e. the voyage, docking and undocking manoeuvres,periods alongside, cargo and ballast operations, etc.);.2

provisions and arrangements for thickness measurements (i.e. access,cleaning/de-scaling, illumination, ventilation, personal safety);.3extent of the thickness measurements;.4

acceptance criteria (refer to the list of minimum thicknesses);.5

extent of close-up survey and thickness measurement considering the coating
condition and suspect areas/areas of substantial corrosion;.6

execution of thickness measurements;.7

taking representative readings in general and where uneven corrosion/pitting
is found;.8

mapping of areas of substantial corrosion; andPage 28 of 127

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Z10.5(cont).9communication between attending surveyor(s) the thickness measurement
firm operator(s) and owner representative(s) concerning findings.

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6.

DOCUMENTATION ON BOARD

6.1

General6.1.1 The Owner is to obtain, supply and maintain on board documentation as specified in
6.2 and 6.3, which is to be readily available for the Surveyor.
6.1.2 The documentation is to be kept on board for the life time of the ship.
6.1.3 For tankers and bulk carriers subject to SOLAS Chapter II-1 Part A-1 Regulation 3-10,
the Owner is to arrange the updating of the Ship Construction File (SCF) throughout the
ship’s life whenever a modification of the documentation included in the SCF has taken place.
Documented procedures for updating the SCF are to be included within the Safety
Management System.
6.2

Survey report file

6.2.1 A Survey Report File is to be a part of the documentation on board consisting of• reports of structural surveys,• Executive Hull Summary,• thickness measurement reports.
6.2.2 The Survey Report File is to be available also in the Owner's and the Classification
Society's management offices.
6.3

Supporting documents

6.3.1 The following additional documentation is to be available onboard:• Survey Programme as required by 5.1 until such time as the Special Survey orIntermediate Survey, as applicable, has been completed,• Main structural plans of cargo holds and ballast tanks (for CSR ships these plans

are to include for each structural element both the as-built and renewal thickness.
Any thickness for voluntary addition is also to be clearly indicated on the plans. The
midship section plan to be supplied on board the ship is to include the minimum
allowable hull girder sectional properties for hold transverse section in all cargoholds),• Previous repair history,• Cargo and ballast history,• Inspection by ship's personnel with reference to- Structural deterioration in general,- Leakage in bulkheads and piping,- Condition of corrosion prevention system, if any.
- A guidance for reporting is shown in Table III• Any other information that will help identify critical structural areas and/or Suspect
Areas requiring inspection.
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6.3.2 For tankers and bulk carriers subject to SOLAS Chapter II-1 Part A-1 Regulation 3-10,
the Ship Construction File (SCF), limited to the items to be retained on board, is to beavailable on board.
6.4

Review of documentation on board

6.4.1 Prior to survey, the Surveyor is to examine the completeness of the documentation
onboard, and its contents as a basis for the survey.
6.4.2 For tankers and bulk carriers subject to SOLAS Chapter II-1 Part A-1 Regulation 3-10,
on completion of the survey, the surveyor is to verify that the update of the Ship Construction
File (SCF) has been done whenever a modification of the documentation included in the SCF
has taken place.
6.4.2.1 For the SCF stored on board ship, the surveyor is to examine the information on
board ship.
In cases where any major event, including, but not limited to, substantial repair andconversion, or any modification to the ship structures, the surveyor is to also verify that the
updated information is kept on board the ship.
If the updating of the SCF onboard is not completed at the time of survey, the Surveyor
records it and requires confirmation at the next periodical survey.
6.4.2.2 For the SCF stored on shore archive, the surveyor is to examine the list of information
included on shore archive.
In cases where any major event, including, but not limited to, substantial repair andconversion, or any modification to the ship structures, the surveyor is to also verify that the
updated information is stored on shore archive by examining the list of information included
on shore archive or kept on board the ship.
In addition, the surveyor is to confirm that the service contract with of the Archive Center isvalid.
If the updating of the SCF Supplement ashore is not completed at the time of survey, theSurveyor records it and requires confirmation at the next periodical survey.
6.4.3 For tankers and bulk carriers subject to SOLAS Chapter II-1 Part A-1 Regulation 3-10,
on completion of the survey, the surveyor is to verify any addition and/or renewal of materials
used for the construction of the hull structure are documented within the Ship Construction
File inventory list.

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7.

PROCEDURES FOR THICKNESS MEASUREMENT

7.1

General7.1.1 The required thickness measurements, if not carried out by the Classification Society
itself, are to be witnessed by a Surveyor of the Society. The Surveyor is to be on board to theextent necessary to control the process.
7.1.2 The thickness measurement firm is to be part of the survey planning meeting to beheld prior to commencing the survey.
7.1.3
Thickness measurements of structures in areas where close-up surveys are required
shall be carried out simultaneously with close-up surveys.
7.1.4 In all cases the extent of thickness measurements is to be sufficient as to represent
the actual average condition.
7.2

Certification of thickness measurement firm

7.2.1 The thickness measurement is to be carried out by a qualified firm certified by theClassification Society according to principles stated in Table V VI.
7.3

Number and locations of measurements

7.3.1 Application
The item 7.3 only applies to vessels built under the IACS Common Structural Rules 1. For
vessels not built under IACS Common Structural Rules, the requirements for number andlocations of measurements are according to the Rules of the individual Classification Society
and/or specific IACS URs depending on ship’s age and structural elements concerned.
7.3.2 Number of measurements
Considering the extent of thickness measurements according to the different structuralelements of the ship and surveys (special, intermediate and annual), the locations of thepoints to be measured are given for the most important items of the structure.
7.3.3 Locations of measurements
Table 1 provides explanations and/or interpretations for the application of those requirements
indicated in the Rules, which refer to both systematic thickness measurements related to thecalculation of global hull girder strength and specific measurements connected to close-up
surveys.
Fig 4 to Fig 9 are provided to facilitate the explanations and/or interpretations given in Table 1,
to show typical arrangements of double side skin bulk carriers.

1 IACS Common Structural Rules mean IACS Common Structural Rules for Bulk Carriers (IACS CSR for Bulk

Carriers) or IACS Common Structural Rules for Bulk Carriers and Oil Tankers (IACS CSR BC&OT).

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Z10.5(cont)

Table 1: Interpretations of rule requirements for the locations and number of points tobe measured for CSR bulk carriers (double skin)
Item
Selected plates on deck,tank top, bottom, double
bottom and wind-andwater area
All deck, tank top andbottom plates and windand-water strakes

Transverse section

All cargo hold hatch
covers and coamings
Transverse section ofdeck plating outside line ofcargo hatch openings

All deck plating andunderdeck structure inside
line of hatch openings
between cargo holdhatchesInterpretation«Selected» means at leasta single point on one outof three plates, to bechosen on representative
areas of average corrosion
At least two points oneach plate to be taken
either at each 1/4
extremity of plate or atrepresentative areas of
average corrosion
A transverse section
includes all longitudinal
members such as plating,longitudinals and girders
at the deck, sides, bottom,
inner bottom, hopper
sides, inner sides and top
wing inner sides.
Including plates andstiffeners
Two single points on eachdeck plate (to be taken
either at each 1/4
extremity of plate or atrepresentative areas of
average corrosion)
between the ship sides
and hatch coamings in thetransverse section
concerned«All deck plating» means
at least two points on eachplate to be taken either at
each 1/4 extremity of plateor at representative areasof average corrosion.

Figure reference

Fig 4

Locations of points are
given in Fig 5

Extent of areas is shownin Fig 10
Locations of points are
given in Fig 9“Under deck structure”: ateach short longitudinal
girder: three points for web
plating (fwd/middle/aft),single point for face plate,
one point for web plating
and one point for faceplating of transverse beam
in way. At each ends oftransverse beams, one
point for web plating andone point for face plating
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Z10.5(cont)

Item
Transverse frame indouble skin tankTransverse bulkheads incargo holds

One transverse bulkheadin each cargo holdTransverse bulkheads in
one topside, hopper anddouble bottom ballast tankTransverse webs in ballast
tanks

Interpretation

Figure reference
Fig 4

Includes bulkhead plating,stiffeners and girders,
including internal structureof upper and lower stools,
where fitted. Two selectedbulkheads: one is to be
the bulkhead between thetwo foremost cargo holds
and the second may bechosen in other positions
This means that the closeup survey and related
thickness measurements
are to be performed on
one side of the bulkhead;
the side is to be chosen
based on the outcome ofthe overall survey of bothsides. In the event of
doubt, the Surveyor may
also require (possibly
partial) close-up survey on
the other side
Includes bulkhead andstiffening systems.

Areas of measurements
are shown in Fig 10

The ballast tank is to bechosen based on thehistory of ballasting among
those prone to have themost severe conditions
Includes web plating, faceplates, stiffeners andassociated plating andlongitudinals.
One of the representative
tanks of each type (i.e.
topside or hopper or sidetank) is to be chosen in
the forward part

Page 34 of 127

Locations of points are
given in Fig 7

Areas of measurements
are shown in Fig 10
Locations of points are
given in Fig 7

Locations of points are
given in Fig 8

Areas of measurements
are shown in Fig 10
Locations of points are
given in Fig 6

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Z10.5

Z10.5(cont)

Note: Measurements are to be taken on both port and starboard sides of the selectedtransverse section.
Figure 4 - Transverse section of a double skin bulk carrier

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Z10.5(cont)

Notes:
1.

Three sections at L/4, L/2, 3L/4 of hatch cover length, including:• one measurement of each hatch cover plate and skirt plate• measurements of adjacent beams and stiffeners• one measurement of coaming plates and coaming flange, each side2.

Measurements of both ends of hatch cover skirt plate, coaming plate and coaming
flange3.

One measurement (two points for web plate and one point for face plate) of one out of
three hatch coaming brackets and bars, on both sides and both ends
Figure 5 - Locations of measurements on hatch covers and coamings

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Z10.5

Z10.5(cont)

Figure 6 - Locations of measurements on structural members in ballast tanks ofdouble skin bulk carriers (topside or hopper or side tank)

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Z10.5

Z10.5(cont)

Note: Measurements to be taken in each shaded area as per views A - A and B - B
Figure 7 - Locations of measurements on cargo hold transverse bulkheads(additional measurements to internal structure of upper and lower stools to be added,
e.g. two points in the upper and two points in the lower stools to be indicated in
section A - A)

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Z10.5

Z10.5(cont)

Note: Measurements to be taken in each vertical section as per view A - A
Figure 8 - Locations of measurements on transverse bulkheads of topside, hopper anddouble bottom tanks (two additional measurements to internal structure of double
bottom tank to be added at midspan)

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Z10.5

Z10.5(cont)

Figure 9 - Locations of measurements on underdeck structure
7.4

Reporting

7.4.1 A thickness measurement report is to be prepared. The report is to give the location of
measurement, the thickness measured as well as corresponding original thickness.
Furthermore, the report is to give the date when the measurements were carried out, type ofmeasuring equipment, names of personnel and their qualifications and has to be signed by
the operator.
The thickness measurement report is to follow the principles as specified in the
Recommended Procedures for Thickness Measurement of Double Skin Bulk Carriers,
contained in Annex II.
7.4.2 The Surveyor is to review the final thickness measurement report and countersign the
cover page.

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Z10.5

Z10.5(cont)

8.

ACCEPTANCE CRITERIA

8.1

General8.1.1 For vessels built under IACS Common Structural Rules, the Acceptance Criteria is
according to IACS Common Structural Rules 1 and as specified in 8.2, 8.3 and 8.4.
8.1.2 For vessels not built under IACS Common Structural Rules, the Acceptance Criteria
are according to the Rules of the individual Classification Society and/or specific IACS URs
depending on ship’s age and structural elements concerned, e.g. UR S18 for corrugatedtransverse watertight bulkheads, UR S19 for the transverse watertight corrugated bulkhead
between Cargo Holds Nos. 1 and 2, and UR S21 for all cargo hatch covers and hatch forward
and side coamings on exposed decks in position 1 (as defined in ILLC), as applicable.
8.2

Acceptance criteria for pitting corrosion of CSR ships

8.2.1 Side structures
If pitting intensity in an area where coating is required, according to IACS Common Structural
Rules 2, is higher than 15% (see Figure 1), thickness measurements are to be performed tocheck the extent of pitting corrosion. The 15% is based on pitting or grooving on only one
side of a plate.
In cases where pitting is exceeding 15%, as defined above, an area of 300 mm or more, atthe most pitted part of the plate, is to be cleaned to bare metal and the thickness is to bemeasured in way of the five deepest pits within the cleaned area. The least thickness
measured in way of any of these pits is to be taken as the thickness to be recorded.
The minimum remaining thickness in pits, grooves or other local areas is to be greater than
70% of the as-built thickness, in the side shell, hopper tank and topside tank plating attachedto the each side frame, over a width up to 30 mm from each side of it, without being greaterthan tren.
8.2.2 Other structures
For plates with pitting intensity less than 20%, see Figure 1, the measured thickness, tm of
any individual measurement is to meet the lesser of the following criteria:
tm ≥ 0.7 (tas-built - tvol add) mm
tm ≥ tren - 1 mm
Where:
tas-built

As-built thickness of the member, in mm

tvol add

Voluntary thickness addition; thickness, in mm, voluntarily added as the
Owner’s extra margin for corrosion wastage in addition to tC

tren

Renewal thickness; minimum allowable thickness, in mm, below which
renewal of structural members is to be carried out

1 Ch.13 of IACS CSR for Bulk Carriers, or Ch. 13, Part 1 of IACS CSR BC&OT

2 Sec. 5, Ch. 3 of IACS CSR for Bulk Carriers, or Sec. 4, Ch. 3, Part 1 of IACS CSR BC&OT

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tC

Total corrosion addition, in mm, defined in IACS Common Structural Rules 1

tm

Measured thickness, in mm, on one item, i.e. average thickness on one item
using the various measurements taken on this same item during periodical
ship’s in service surveys.

The average thickness across any cross section in the plating is not to be less than the
renewal criteria for general corrosion given in Chapter 13 of CSR.
8.3

Acceptance criteria for edge corrosion of CSR ships

8.3.1 Provided that the overall corroded height of the edge corrosion of the flange, or web in
the case of flat bar stiffeners, is less than 25%, see Figure 2, of the stiffener flange breadth or
web height, as applicable, the measured thickness, tm, is to meet the lesser of the following
criteria:
tm ≥ 0.7 (tas-built - tvol add) mm
tm ≥ tren - 1 mm
8.3.2 The average measured thickness across the breadth or height of the stiffener is not tobe less than that defined in IACS Common Structural Rules 2.
8.3.3 Plate edges at openings for manholes, lightening holes etc. may be below theminimum thickness given in IACS Common Structural Rules2 provided that:(a)the maximum extent of the reduced plate thickness, below the minimum given in IACS
Common Structural Rules2, from the opening edge is not more than 20% of the smallest
dimension of the opening and does not exceed 100mm.

(b)rough or uneven edges may be cropped-back provided that the maximum dimensionof the opening is not increased by more than 10% and the remaining thickness of the
new edge is not less than tren - 1 mm.

8.4

Acceptance criteria for grooving corrosion of CSR ships

8.4.1 Where the groove breadth is a maximum of 15% of the web height, but not more than
30mm, see Figure 3, the measured thickness, tm, in the grooved area is to meet the lesser ofthe following criteria:
tm ≥ 0.75 (tas-built - tvol add) mm
tm ≥ tren - 0.5 mm
but is not to be less thantm = 6 mm
8.4.2 Structural members with areas of grooving greater than those in 8.4.1 above are to beassessed based on the criteria for general corrosion as defined in IACS Common Structural
Rules2 using the average measured thickness across the plating/stiffener.

1 Sec. 3, Ch. 3 of IACS CSR for Bulk Carriers, or Sec. 3, Ch. 3, Part 1of IACS CSR BC & OT
2 Ch.13 of IACS CSR for Bulk Carriers, or Ch. 13, Part 1 of IACS CSR BC&OT

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Z10.5(cont)

9

REPORTING AND EVALUATION OF SURVEY

9.1

Evaluation of survey report

9.1.1 The data and information on the structural condition of the vessel collected during thesurvey is to be evaluated for acceptability and continued structural integrity of the vessel.
9.1.1.1 For CSR bulk carriers, the ship’s longitudinal strength is to be evaluated by using the
thickness of structural members measured, renewed and reinforced, as appropriate, during
the special surveys carried out after the ship reached 15 years of age (or during the special
survey no. 3, if this is carried out before the ship reaches 15 years) in accordance with thecriteria for longitudinal strength of the ship’s hull girder for CSR bulk carriers specified in IACS
Common Structural Rules 1.
9.1.1.2 The final result of evaluation of the ship’s longitudinal strength required in 9.1.1.1,
after renewal or reinforcement work of structural members, if carried out as a result of initial
evaluation, is to be reported as a part of the Executive Hull Summary.
9.2

Reporting9.2.1 Principles for survey reporting are shown in Table VI VII.
9.2.2 When a survey is split between different survey stations, a report is to be made foreach portion of the survey. A list of items examined and / or tested (pressure testing,thickness measurements etc.) and an indication of whether the item has been credited, are to
be made available to the next attending Surveyor(s), prior to continuing or completing thesurvey.
9.2.3 An Executive Hull Summary of the survey and results is to be issued to the Owner asshown in Table VII VIII and placed on board the vessel for reference at future surveys. The
Executive Hull Summary is to be endorsed by the Classification Society's head office orregional managerial office.

1 Ch.13 of IACS CSR for Bulk Carriers, or Ch. 13, Part 1 of IACS CSR BC&OT

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Z10.5

Z10.5(cont)TABLE I / Sheet I
MINIMUM REQUIREMENTS FOR CLOSE-UP SURVEY AT SPECIAL HULL SURVEY OF
DOUBLE SKIN BULK CARRIERS, EXCLUDING ORE CARRIERSSpecial Survey
No.1
age ≤ 5
One transverse web
with associated plating
and longitudinals in two
representative waterballast tanks of each
type. (This is to include
the foremost topsideand double side waterballast tanks on either
side)
(A)

Special Survey
No.2
5 < age ≤ 10
One tranverse web withassociated plating andlongitudinals asapplicable in eachwater ballast tank.
(A)

Special Survey
No.3
10 < age ≤ 15
All tranverse webs withassociated plating andlongitudinals asapplicable in eachwater ballast tank.
(A)

Special Survey
No.4 and subsequent
age > 15
All tranverse webs withassociated plating andlongitudinals asapplicable in eachwater ballast tank.
(A)

Forward and afttransverse bulkheads
including stiffening
system in a transverse
section including
topside, hopper sideand double side ballast
tanks on one side of
the ship (i.e. port or
starboard).
(A)

All transverse
bulkheads including
stiffening system ineach water ballast tank.
(A)

All transverse
bulkheads including
stiffening system ineach water ballast tank.
(A)

25% of ordinarytransverse frames
for transverse framing
system or 25% of
longitudinals forlongitudinal framing
system on side shelland inner side plating
at forward, middle andaft parts, in all doubleside tanks.
(B)

All ordinary transverse
frames for transverse
framing system or all of
longitudinals forlongitudinal framing
system on side shelland inner side plating
at forward, middle andaft parts, in all doubleside tanks.
(B)

25% of ordinarytransverse frames
for transverse framing
system or 25% of
longitudinals forlongitudinal framing
system on side shelland inner side plating
at forward, middle andaft parts, in theforemost double sidetanks.
(B)

Two selected cargohold transverse
bulkheads, includinginternal structure ofupper and lower stools,
where fitted.
(C)
All cargo hold hatch
covers and coamings(platings andstiffeners).
(D)

One transverse
bulkhead in each cargohold, including internal
structure of upper andlower stools, where
fitted.
(C)
All cargo hold hatch
covers and coamings(platings andstiffeners).
(D)

Areas (C) – (E) as forage interval 10 to 15
years.

All cargo holdtransverse bulkheads,
including internal
structure of upper andlower stools, where
fitted.
(C)
All cargo hold hatch
covers and coamings(platings andstiffeners).
(D)

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Z10.5All deck plating andunder deck structure
inside line of hatch
openings between all
cargo hold hatches.
(E)

Z10.5
(cont)All deck plating andunder deck structure
inside line of hatch
openings between all
cargo hold hatches.
(E)(A), (B), (C), (D) and (E) are areas to be subjected to close-up surveys and thickness measurements(see Figure 10 and 11).
(A):

Transverse web frame or watertight transverse bulkhead in topside, hopper side and doubleside ballast tanks. In fore and aft peak tanks transverse web frame means a complete
transverse web frame ring including adjacent structural members(B):

Ordinary transverse frame in double side tanks(C):

Cargo hold transverse bulkheads plating, siffeners and girders(D):

Cargo hold hatch covers and coamings. Subject to cargo hold hatch covers of approved design
which structurally have no access to the internals, close-up survey/thickness measurement
shall be done of accessible parts of hatch covers structures.

(E):

Deck plating and under deck structure inside line of hatch openings between cargo holdhatches

Note: Close-up survey of transverse bulkheads to be carried out at four levels:
Level (a):Immediately above the inner bottom and immediately above the line of gussets (iffitted) and shedders for ships without lower stool.

Level (b):Immediately above and below the lower stool shelf plate (for those ships fitted withlower stools), and immediately above the line of the shedder plates.

Level (c):Above mid-height of the bulkhead.

Level (d):Immediately below the upper deck plating and immediately adjacent to the upper wingtank, and immediately below the upper stool shelf plate for those ships fitted withupper stools, or immediately below the topside tanks.

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Z10.5

Z10.5(cont)TABLE I / Sheet 2
MINIMUM REQUIREMENTS FOR CLOSE-UP SURVEY AT SPECIAL HULLSURVEY OF ORE CARRIERSSpecial Survey
No.1
age ≤ 5Special Survey
No.2
5 < age ≤ 10

Special Survey
No.3
10 < age ≤ 15

One web frame ring
complete including
adjacent structuralmembers in a ballast
wing tank.
(A)

All web frame rings
complete including
adjacent structuralmembers in a ballast
wing tank.
(A)

All web frame rings
complete including
adjacent structuralmembers in each ballast
tank.
(A)

One transverse
bulkhead lower part including girder
system and adjacentstructural members in a ballast tank.
(A)

One deck transverse
including adjacentdeck structuralmembers in eachremaining ballast tank.
(A)

All transverse bulkheads
complete - including
girder system andadjacent structuralmembers - in eachballast tank.
(A)

Forward and afttransverse bulkheads
complete - including
girder system andadjacent structuralmembers - in a ballast
wing tank.
(A)

One web frame ring
complete including
adjacent structuralmembers in each wing
void space.
(A)

One transverse
bulkhead lower part including girder
system and adjacentstructural members in each remaining
ballast tank.
(A)
One transverse
bulkhead in eachcargo hold, includinginternal structure ofupper and lower
stools, where fitted.
(C)
All cargo hold hatch
covers and coamings(plating and stiffeners).
(D)

Additional web framerings in void spaces as
deemed necessary by
the Classification
Society.
(A)

All deck plating andunder deck structure
inside line of hatch
openings between all
cargo hold hatches.
(E)

All deck plating andunder deck structure
inside line of hatch
openings between all
cargo hold hatches.
(E)

Two selected cargohold transverse
bulkheads, includinginternal structure ofupper and lower
stools, where fitted.
(C)
All cargo hold hatch
covers and coamings(plating andstiffeners).
(D)

All cargo hold transverse
bulkheads, includinginternal structure ofupper and lower stools,
where fitted.
(C)

Special Survey
No.4
and subsequent
age > 15
As for Special Survey forage from 10 to 15 years.

Areas (C) - (E) as for age
interval 10 to 15 years.

All cargo hold hatch
covers and coamings(plating and stiffeners).
(D)

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Z10.5

Z10.5(cont)(A), (C), (D) and (E) are areas to be subjected to close-up surveys and thickness measurements(see Figure 10 and Figure 11).
(A):

Transverse web frame or watertight transverse bulkhead in ballast wing tanks and void
spaces. In fore and aft peak tanks transverse web frame means a complete transverse web
frame ring including adjacent structural members(C):

Cargo hold transverse bulkheads plating, stiffeners and girders(D):

Cargo hold hatch covers and coamings. Subject to cargo hold hatch covers of approved design
which structurally have no access to the internals, close-up survey/thickness measurement
shall be done of accessible parts of hatch covers structures.

(E):

Deck plating and under deck structure inside line of hatch openings between cargo holdhatches

Note:

Close-up Survey of transverse bulkheads to be carried out at four levels:

Level (a):Immediately above the inner bottom and immediately above the line of gussets (if fitted)
and shedders for ships without lower stool.

Level (b):Immediately above and below the lower stool shelf plate (for those ships fitted with lower
stools), and immediately above the line of the shedder plates.

Level (c):About mid-height of the bulkhead.

Level (d):Immediately below the upper deck plating and immediately adjacent to the upper wingtank, and immediately below the upper stool shelf plate for those ships fitted with upperstools, or immediately below the topside tanks.

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Z10.5

Z10.5(cont)TABLE IIMINIMUM REQUIREMENTS FOR THICKNESS MEASUREMENTS AT SPECIAL HULLSURVEY OF DOUBLE SKIN BULK CARRIERSSpecial Survey
No.1
age ≤ 5Suspect areas

Special Survey
No.2
5 < age ≤ 10
Suspect areas

Special Survey
No.3
10 < age ≤ 15
Suspect areas

Special Survey
No.4 and subsequent
age > 15
Suspect areas

Within the cargo
length:Within the cargo length:

Within the cargo length:- each deck plateoutside line of cargo
hatch openings- each deck plateoutside line of cargo
hatch openings- two transverse
sections, one in theamidship area,
outside line of cargo
hatch openings- three transverse
sections, one in theamidship area,
outside line of cargo
hatch openings- all wind and water
strakes
Selected wind andwater strakes outside
the cargo length area

- each bottom plate

Measurements, forgeneral assessment
and recording of
corrosion pattern, of
those structuralmembers subject toclose-up survey
according toTable I/Sheet 1 orTable I/Sheet 2, asapplicable.

Measurements, forgeneral assessment
and recording of
corrosion pattern, of
those structuralmembers subject toclose-up survey
according toTable I/Sheet 1 orTable I/Sheet 2, asapplicable.

- Two transverse
sections of deck
plating outside line ofcargo hatch openings

Wind and water strakes
in way of the twotransverse sections
considered above
Selected wind andwater strakes outside
the cargo length area
Measurements, forgeneral assessment
and recording of
corrosion pattern, of
those structuralmembers subject toclose-up survey
according toTable I/Sheet 1 orTable I/Sheet 2, asapplicable.

Page 48 of 127

All wind and water
strakes, full length

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Z10.5(cont)TABLE III
Ship Name: ................................
OWNERS INSPECTION REPORT - Structural Condition
For Tank/Hold No: .......................
Grade of Steel:

Deck
Bottom: .................
: .................

Elements
Other

BucklesCorrosion

CracksSide
Long. Bhd
Coating
cond.

Pitting: .................
: .................
Mod.
/Rep.

Deck:

Bottom:

Side:

Long.
Bulkheads:
Transv.
Bulkheads:
Repairs carried out due to:Thickness measurements carried out, dates:
Results in General:
Overdue Surveys:
Outstanding Conditions of class:Comments:*Repairs are to be surveyed by the classification society

Date ofInspection:
Inspected by:
Signature:

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Z10.5

Z10.5(cont)TABLE III IV/ Sheet 1
REQUIREMENTS FOR EXTENT OF THICKNESS MEASUREMENTS AT THOSE AREAS
OF SUBSTANTIAL CORROSION OF DOUBLE SKIN BULK CARRIERS WITHIN THE
CARGO LENGTH AREA
BOTTOM, INNER BOTTOM AND HOPPER STRUCTURE
Structural member

Extent of measurement

Pattern of measurement

Bottom, inner bottom andhopper structure plating

Minimum of three bays
across double bottom tank,including aft bay

Five-point pattern for eachpanel between longitudinals
and floors

Bottom, inner bottom andhopper structure longitudinals
Bottom girders, including thewatertight ones

Bottom floors, including thewatertight ones

Hopper structure web framering
Hopper structure transverse
watertight bulkhead or swash
bulkhead

Measurements around andunder all suction bell mouths
Minimum of threelongitudinals in each bay
where bottom plating
measured
At fore and aft watertightfloors and in centre of tanks

Three floors in the bays
where bottom plating
measured, withmeasurements at both ends
and middle
Three floors in bays where
bottom plating measured- lower 1/3 of bulkhead- upper 2/3 of bulkhead- stiffeners(minimum of three)

Plate stiffening

Where applicable

Page 50 of 127

Three meaurements in line
across the flange and threemeasurements on the vertical
web
Vertical line of single
measurements on girder
plating with one
measurement between eachpanel stiffener, or a minimumof three measurements
Five-point pattern over twosquare metre area

Five-point pattern over one
square metre of plating
Single measurements onflange- five-point pattern over
one square metre ofplating- five-point pattern overtwo square metre ofplating- For web, five-point
pattern over span (twomeasurements across
web at each end
and one at centre ofspan). For flange, single
measurements at eachend and centre of spanSingle measurements

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Z10.5

Z10.5(cont)TABLE III IV / Sheet 2
REQUIREMENTS FOR EXTENT OF THICKNESS MEASUREMENTS AT THOSE AREAS
OF SUBSTANTIAL CORROSION OF DOUBLE SKIN BULK CARRIERS WITHIN THE
CARGO LENGTH AREA
DECK STRUCTURE INCLUDING CROSS STRIPS, MAIN CARGO HATCHWAYS, HATCH
COVERS, COAMINGS AND TOPSIDE TANKS
Structural member

Extent of measurement

Cross Deck Strip plating

Suspect Cross Deck Strip plating

Underdeck Stiffeners

Transverse members
Longitudinal member

Hatch Covers

Hatch Coamings
Topside Ballast Tanks

Topside Ballast Tanks

Topside Ballast TanksSide and end skirts, each threelocations

Pattern of measurement
Five-point pattern between
underdeck siffeners over 1 metre
lengthFive-point pattern at each end andmid spanFive-point pattern on both web andflangeFive-point pattern at each location

Three longitudinal bands, outboard
strakes (2) and centreline strake (1)Each side and end of coaming, one
band lower 1/3, one band upper 2/3
of coaminga) watertight transverse bulkheads:

Five-point measurement each band

- Lower 1/3 of bulkhead

Five-point pattern over
1 sq. metre of plating- Upper 2/3 of bulkhead

Five-point pattern over
1 sq. metre of plating- Stiffeners

Five-point pattern over
1 metre lengthFive-point measurement each bandi.e. end or side coamingb) two representative swash
transverse bulkheads:- Lower 1/3 of bulkhead

Five-point pattern over
1 sq. metre of plating- Upper 2/3 of bulkhead

Five-point pattern over
1 sq. metre of plating- Stiffeners

Five-point pattern over
1 metre lengthc) three representative bays of slope
plating- Lower 1/3 of tank

Five-point pattern over
1 sq. metre of plating- Upper 2/3 of tank

Five-point pattern over
1 sq. metre of plating

Main Deck Platingd) Longitudinals, suspect andadjacent
Suspect plates and adjacent (4)Five-point pattern on both web andflange over 1 metre lengthFive-point pattern over
1 sq. metre of plating

Main Deck Longitudinals

Suspect Plates

Web Frames/Transverses

Suspect PlatesFive-point pattern on both web andflange over 1 metre lengthFive-point pattern over
1 sq. metre

Topside Ballast Tanks

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Z10.5

Z10.5(cont)TABLE III IV / Sheet 3
REQUIREMENTS FOR EXTENT OF THICKNESS MEASUREMENTS AT THOSE AREAS
OF SUBSTANTIAL CORROSION OF DOUBLE SKIN BULK CARRIERS WITHIN THE
CARGO LENGTH AREASTRUCTURE IN DOUBLE SIDE SPACES OF DOUBLE SKIN BULK CARRIERS INCLUDINGWING VOID SPACES OF ORE CARRIERSStructural member

Extent of measurement

Pattern of measurement

Side shell and inner plating:- Upper strake andstrakes in way ofhorizontal girders- Plating between eachpair of transverse
frames / longitudinals ina minimum of threebays (along the tank)- Single measurement- All other strakes- Plating between every thirdpair of longitudinals in same
three bays

- Single measurement- upper strake- Each transverse frame /longitudinal in same
three bays

- Three measurements
across web and 1
measurement on flange- all other strakes- Every third transverse
frame / longitudinal insame three bays
Minimum of three at top,
middle and bottom of tank insame three bays

- Three measurements
across web and 1
measurement on flange
Five-point pattern over areaof bracket- strakes in way ofhorizontal girders- Minimum of two webs
and both transverse
bulkeads- Five-point pattern overapprox. two square
metre area

- other strakes- Minimum of two webs
and both transverse
bulkeads- Two measurements
between each pair ofvertical stiffeners

Horizontal girders

Plating on each girder in aminimum of three bays

Plate stiffening

Where applicable

Two measurements between
each pair of longitudinal
girder stiffeners
Single measurements

Side shell and inner sidetransverse frames /longitudinals on:

Transverse frames /Longitudinals- brackets
Vertical web and transverse
bulkheads:

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Z10.5

Z10.5(cont)TABLE III IV / Sheet 4
REQUIREMENTS FOR EXTENT OF THICKNESS MEASUREMENTS AT THOSE AREAS
OF SUBSTANTIAL CORROSION OF DOUBLE SKIN BULK CARRIERS WITHIN THE
CARGO LENGTH AREA
TRANSVERSE BULKHEADS IN CARGO HOLDS
Structural member
Lower stool, where fitted

Transverse bulkheads

Extent of measurement

Pattern of measurement- Transverse band within
25mm of welded
connection to inner
bottom- Five-point pattern
between stiffeners overone metre length- Transverse bands
within 25mm of welded
connection to shelf
plate- Transverse band at
approximately midheight- Five-point pattern
between stiffeners overone metre length- Transverse band at partof bulkhead adjacent toupper deck or below
upper stool shelf plate(for those ships fitted withupper stools)- Five-point pattern over
one square metre ofplating

Page 53 of 127- Five-point pattern over
one square metre ofplating

IACS Req. 2003/Rev.20 2023

Z10.5

Z10.5(cont)TABLE IV V
MINIMUM REQUIREMENTS OF OVERALL AND CLOSE-UP SURVEY AND THICKNESSMEASUREMENTS AT INTERMEDIATE SURVEY OF DOUBLE SKIN BULK CARRIERSAge of ship at time of intermediate survey due date
5 < age ≤ 10
Overall survey ofRepresentative ballast tanks
selected by the attending
surveyor (the selection is toinclude fore and aft peak tanks
and a number of other tanks,
taking into account the total
number and type of ballast
tanks)Overall and close-up survey ofSuspect Areas identified at
previous surveys

10 < age ≤ 15
The requirements of theprevious special survey

age > 15
The requirements of theprevious special survey(see 4.2.3)(see 4.2.4)

Overall survey of all cargo holds
Thickness measurements to an
extent sufficient to determine
both general and local corrosion
levels at areas subject to closeup survey at ‘suspect areas’
identified at previous surveys

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Z10.5TABLE V VI

Z10.5

PROCEDURES FOR CERTIFICATION OF FIRMS ENGAGED IN THICKNESSMEASUREMENT OF HULL STRUCTURES(cont)

1.

Application
This guidance applies for certification of the firms which intend to engage in the
thickness measurement of hull structures of the vessels.

2.

Procedures for Certification(1)

Submission of Documents:
Following documents are to be submitted to the Society for approval:

(2)

a)

Outline of firm, e.g. organization and management structure.

b)

Experience of the firm on thickness measurement inter alia of hull structures ofthe vessels.

c)Technicians’ careers, i.e. experience of technicians as thickness measurement
operators, technical knowledge of hull structure, etc. Operators, are to bequalified according to a recognized industrial NDT Standard.

d)Equipment used for thickness measurement such as ultra-sonic testingmachines and its maintenance/calibration procedures.

e)

A guide for thickness measurement operators.

f)Training programmes of technicians for thickness measurement.

g)Measurement record format in accordance with the Recommended
Procedures for Thickness Measurements of Bulk Carriers, contained in Annex
II.

Auditing of the firm:Upon reviewing the documents submitted with satisfactory results, the firm is audited
in order to ascertain that the firm is duly organised and managed in accordance withthe documents submitted, and eventually is capable of conducting thickness
measurement of the hull construction of the ships.

(3)

Certification is conditional on an onboard demonstration at thickness measurements
as well as satisfactory reporting.

3.

Certification(1)

Upon satisfactory results of both the audit of the firm in 2(2) and the demonstration
tests in 2(3) above, the Society will issue a Certificate of Approval as well as a noticeto the effect that the thickness measurement operation system of the firm has beencertified by the Society.

(2)

Renewal/endorsement of the Certificate is to be made at intervals not exceeding 3
years by verification that original conditions are maintained.
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Z10.5Z10.5

4.

(cont)

Information of any alteration to the Certified Thickness Measurement Operation
SystemIn case where any alteration to the certified thickness measurement operation systemof the firm is made, such an alteration is to be immediately informed to the Society.
Re-audit is made where deemed necessary by the Society.

5.

Cancellation of Approval
Approval may be cancelled in the following cases:(1)

Where the measurements were improperly carried out or the results were
improperly reported.

(2)

Where the Society's surveyor found any deficiencies in the approved thickness
measurement operation systems of the firm.

(3)

Where the firm failed to inform of any alteration in 4 above to the Society.

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Z10.5TABLE VI VII

Z10.5

SURVEY REPORTING PRINCIPLES(cont)As a principle, for bulk carriers subject to ESP, the surveyor is to include the following content
in his report for survey of hull structure and piping systems, as relevant for the survey.
The structure of the reporting content may be different, depending on the report system forthe respective Societies.
1. General
1.1 A survey report is to be generated in the following cases:- In connection with commencement, continuation and / or completion of periodical hullsurveys, i.e. annual, intermediate and special surveys, as relevant-

When structural damages / defects have been found
When repairs, renewals or modifications have been carried out
When condition of class has been imposed or deleted

1.2 The purpose of reporting is to provide:-

Evidence that prescribed surveys have been carried out in accordance with applicableclassification rules
Documentation of surveys carried out with findings, repairs carried out and conditionof class imposed or deleted
Survey records, including actions taken, which shall form an auditable documentary
trail. Survey reports are to be kept in the survey report file required to be on board
Information for planning of future surveys
Information which may be used as input for maintenance of classification rules andinstructions

1.3 When a survey is split between different survey stations, a report is to be made for eachportion of the survey. A list of items surveyed, relevant findings and an indication of whether
the item has been credited, are to be made available to the next attending surveyor, prior tocontinuing or completing the survey. Thickness measurement and tank testing carried out isalso to be listed for the next surveyor.
2. Extent of the survey
2.1 Identification of compartments where an overall survey has been carried out.
2.2 Identification of locations, in each ballast tank and cargo hold including hatch covers andcoamings, where a close-up survey has been carried out, together with information of themeans of access used.
2.3 Identification of locations, in each ballast tank and cargo hold including hatch covers andcoamings, where thickness measurement has been carried out.
Note:

As a minimum, the identification of location of close-up survey and thickness
measurement is to include a confirmation with description of individual structuralmembers corresponding to the extent of requirements stipulated in UR Z10.2 basedon type of periodical survey and the ship's age.

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Z10.5

Z10.5(cont)

Where only partial survey is required, i.e. 25% of shell frames, one transverse web, twoselected cargo hold transverse bulkheads, the identification is to include location within eachballast tank and cargo hold by reference to frame numbers.
2.4 For areas in ballast tanks and cargo holds where protective coating is found to be in
GOOD condition and the extent of close-up survey and / or thickness measurement has been
specially considered, structures subject to special consideration are to be identified.
2.5 Identification of tanks subject to tank testing.
2.6 Identification of piping systems on deck and within cargo holds, ballast tanks, pipetunnels, cofferdams and void spaces where:-

Examination including internal examination of piping with valves and fittings andthickness measurement, as relevant, has been carried out-

Operational test to working pressure has been carried out

3. Result of the survey
3.1 Type, extent and condition of protective coating in each tank, as relevant (rated GOOD,
FAIR or POOR).
3.2 Structural condition of each compartment with information on the following, as relevant:--Identification of findings, such as:•
Corrosion with description of location, type and extent•
Areas with substantial corrosion•
Cracks / fractures with description of location and extent•
Buckling with description of location and extent•
Indents with description of location and extent
Identification of compartments where no structural damages / defects are foundThe report may be supplemented by sketches / photos.
3.3 Thickness measurement report is to be verified and signed by the surveyor controllingthe measurements on board.
4. Actions taken with respect to findings
4.1 Whenever the attending surveyor is of the opinion that repairs are required, each item tobe repaired is to be identified in the survey report. Whenever repairs are carried out, details of
the repairs effected are to be reported by making specific reference to relevant items in thesurvey report.
4.2 Repairs carried out are to be reported with identification of:Compartment
Structural member
Repair method (i.e. renewal or modification) including:- steel grades and scantlings (if different from the original);- sketches/photos, as appropriate.
Repair extent
NDT / Tests

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Z10.5

Z10.5(cont)

4.3 For repairs not completed at the time of survey, condition of class is to be imposed with a
specific time limit for the repairs. In order to provide correct and proper information to thesurveyor attending for survey of the repairs, condition of class is to be sufficiently detailed
with identification of each item to be repaired. For identification of extensive repairs, reference
may be given to the survey report.

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Z10.5TABLE VII VIII (i)Z10.5

IACS UNIFIED REQUIREMENTS FOR ENHANCED SURVEYSEXECUTIVE HULL SUMMARY(cont)

Issued upon Completion of Special Survey
GENERAL PARTICULARSSHIP’S NAME:

CLASS IDENTIFY NUMBER:
IMO IDENTIFY NUMBER:

PORT OF REGISTRY:NATIONAL FLAG:

DEADWEIGHT (M. TONNES):GROSS TONNAGE:
NATIONAL:
ITC (69):

DATE OF BUILD:

CLASSIFICATION NOTATION:DATE OF MAJOR CONVERSION:
TYPE OF CONVERSION:a)

The survey reports and documents listed below have been reviewed by theundersigned and found to be satisfactoryb)

A summary of the survey is attached herewith on sheet 2c)

The hull special survey has been completed in accordance with the Regulations on[date]

Executive Summary
Report completed by:

Name

OFFICE

DATE

Executive Summary
Report verified by:

Name

OFFICE

DATE

Title

Signature

Title

Signature

Attached reports and documents:
1)
2)
3)
4)
5)
6)
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Z10.5TABLE VII VIII (ii)

Z10.5

EXECUTIVE HULL SUMMARY(cont)A)

General Particulars: -Ref.Table VIII (i)B)

Report Review:-

Where and how survey was done

C)

Close-up Survey:-

Extent (Which tanks)

D)

Thicknessmeasurements:-

Reference to Thickness Measurement report-

Summary of where measured-

Separate form indicating the tanks/areas with
Substantial Corrosion, and corresponding-

Thickness diminution-

Corrosion pattern

E)

Tank / hold /double-side skin
void space Protection -F)

Repairs:

G)

Conditions of Class:

H)

Memoranda:

I)

Conclusion:

Separate form indicating:Location of coating-

Condition of coating (if applicable)-

Identification of tanks/areas-

Acceptable defects-

Any points of attention for future surveys, e.g. forSuspect Areas.

-

Extended Annual/Intermediate survey Examination ofballast tanks and double-side skin void spaces at annual
surveys due to coating breakdown-

Statement on evaluation/verification of survey report

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Z10.5TABLE VII VIII (iii) A – non CSR vessels

Z10.5

EXTRACT OF THICKNESS MEASUREMENT(cont)

Reference is made to the thickness measurements report:

Position ofsubstantiallycorroded
Tanks/Areas or
Areas with deep
pitting1)

Thicknessdiminution[%]Corrosion pattern2)

Remarks:e.g. Ref. attachedsketches

Remarks:
1)

Substantial corrosion, i.e. 75 – 100% of acceptable margins wasted.

2)

P = Pitting; C = Corrosion in General
Any bottom plating with a pitting intensity of 20% or more, with wastage in thesubstantial corrosion range or having an average depth of pitting of 1/3 or more ofactual plate thickness is to be noted.

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Z10.5TABLE VII VIII (iii) B – CSR vessels

Z10.5

EXTRACT OF THICKNESS MEASUREMENTS(cont)

Reference is made to the thickness measurements report:
1)

2)

Position ofsubstantiallycorroded
Tanks/Areas or
Areas with deep
pittingtm - tren (mm)Corrosion pattern

Remarks: e.g. Ref.
Attached sketches

Remarks
1)

Substantial corrosion, an extent of corrosion such that the assessment of the corrosion
pattern indicates a measured thickness between tren + 0.5mm and tren.

2)

P = Pitting
C = Corrosion in General
Areas with deep pitting assessed according to 8.2 are to be recorded in this column.

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Z10.5TABLE VII VIII (iv)

Z10.5

TANK PROTECTION(cont)

Tank/hold/void nos.1)

Tank/hold/void
protection2)

Coating condition3)

Remarks

Remarks:
1)

All ballast tanks, and cargo holds and double-side skin void spaces to be listed.

2)

C = Coating; NP = No Protection

3)

Coating condition according to the following standard:
GOOD

condition with only minor spot rusting.

FAIR

condition with local breakdown at edges of stiffeners and weld
connections and/or light rusting over 20% or more of areas underconsideration, but less than as defined for POOR condition.

POOR

condition with general breakdown of coating over 20% or more of areasor hard scale at 10% or more of areas under consideration.

For ballast tanks, if coating condition less than “GOOD” "POOR" is given, tanks are to be
examined at annual surveys. extended annual surveys are to be introduced. This is to be
noted in part H) of the Executive Hull Summary.
For double-side skin void spaces on bulk carriers exceeding 20 years of age and of 150 m inlength and upwards, if coating condition POOR is given, those voids are to be examined atannual surveys. This is to be noted in part H of Executive Hull Summary.

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Z10.5

Z10.5(cont)

Figure 10 - Close-up survey and thickness measurement areas

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Z10.5

Z10.5(cont)

Figure 11(a) - Close-up survey and thickness measurement areas
ordinary transverse frame in double skin tank

Figure 11(b) - Close-up survey and thickness measurement areas
ordinary longitudinal structure in double skin tank
End ofSection
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Z10.5 Annex I

ANNEX I

Z10.5
(cont)GUIDELINES FOR TECHNICAL ASSESSMENT IN CONJUNCTION WITH PLANNING FOR
ENHANCED SURVEYS OF DOUBLE SKIN BULK CARRIERS SPECIAL
SURVEY– HULL
Contents:
1.

INTRODUCTION

2.
2.1
2.2
2.3
2.4

PURPOSE AND PRINCIPLES
PurposeMinimum Requirements
TimingAspects to be considered

3.

TECHNICAL ASSESSMENT

3.1
3.2

General
Methods
3.2.1 Design Details
3.2.2 Corrosion
3.2.3 Locations for Close-up Survey and Thickness Measurement

REFERENCES
1. IACS, Unified Requirement Z10.5, "Hull Surveys of Double Skin Bulk Carriers"
2. IACS Recommendation 76, "Bulk Carriers: Guidelines for Surveys, Assessment and Repairof Hull Structures – Bulk Carriers, 2007
23. TSCF, "Guidelines for the Inspection and Maintenance of Double Hull Tanker Structures,
1995"
34. TSCF, "Guidance Manual for Tanker Structures, 1997"
1.

INTRODUCTION

These guidelines contain information and suggestions concerning technical assessments,
which may be of use in conjunction with the planning of enhanced Special Surveys of double
skin bulk carriers. As indicated in 5.1.5 of IACS Unified Requirement Z10.5, "Hull Surveys of
Double Skin Bulk Carriers" (Ref. 1), the guidelines are a recommended tool which may be
invoked at the discretion of an IACS Member Society, when considered necessary andappropriate, in conjunction with the preparation of the required Survey Programme.
2.

PURPOSE AND PRINCIPLES

2.1

PurposeThe purpose of the technical assessments described in these guidelines is to assist in
identifying critical structural areas, nominating suspect areas and in focusing attention on
structural elements or areas of structural elements which may be particularly susceptible to,or evidence a history of, wastage or damage. This information may be useful in nominating
locations, areas holds and tanks for thickness measurement, close-up survey and tanktesting.

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Z10.5 Annex I

Z10.5(cont)

Critical Structural Areas are locations which have been identified from calculations to requiremonitoring or from the service history of the subject ship or from similar or sister ships (ifavailable) to be sensitive to cracking, buckling or corrosion which would impair the structural
integrity of the ship.
2.2

Minimum Requirements

However, these guidelines may not be used to reduce the requirements pertaining tothickness measurement, close-up survey and tank testing contained in Tables I and II and inparagraph 2.5, respectively, of Z10.5, which are, in all cases, to be complied with as aminimum.
2.3

TimingAs with other aspects of survey planning, the technical assessments described in theseguidelines should be worked out by the Owner or operator in cooperation with theClassification Society well in advance of the commencement of the Special Survey, i.e. prior
to commencing the survey and normally at least 12 to 15 months before the survey's
completion due date.
2.4

Aspects to be consideredTechnical assessments, which may include quantitative or qualitative evaluation of relative
risks of possible deterioration, of the following aspects of a particular ship may be used as abasis for the nomination of holds, tanks and areas for survey:•

Design features such as stress levels on various structural elements, design details
and extent of use of high tensile steel.

•

Former history with respect to corrosion, cracking, buckling, indents and repairs forthe particular ship as well as similar vessels, where available.

•

Information with respect to types of cargo carried, use of different holds/tanks forcargo/ballast, protection of holds and tanks and condition of coating, if any.

Technical assessments of the relative risks of susceptibility to damage or deterioration ofvarious structural elements and areas are to be judged and decided on the basis ofrecognized principles and practices, such as may be found in publications of IACS (Ref 21)
and Tanker Structure Cooperative Forum (TSCF), (Refs. 32 and 43).
3.

TECHNICAL ASSESSMENT

3.1

GeneralThere are three basic types of possible failure, which may be the subject of technicalassessment in connection with planning of surveys; corrosion, cracks and buckling.
Contact damages are not normally covered by the survey planning since indents are usually
noted in memoranda and assumed to be dealt with as a normal routine by Surveyors.
Technical assessments performed in conjunction with the survey planning process are, in
principle, to be as shown schematically in Figure 1. The approach is basically an evaluationof the risk in the following aspects based on the knowledge and experience related to:
DesignCorrosion.

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Z10.5 Annex I

Z10.5(cont)The design is to be considered with respect to structural details, which may be susceptible tobuckling or cracking as a result of vibration, high stress levels or fatigue.
Corrosion is related to the ageing process, and is closely connected with the quality ofcorrosion prevention systems fitted at new building, and subsequent maintenance during theservice life. Corrosion may also lead to cracking and/or buckling.
3.2

Methods

3.2.1

Design Details

Damage experience related to the ship in question and sister and/or similar ships, whereavailable, is the main source of information to be used in the process of planning. In addition,a selection of structural details from the design drawings is to be included.
Typical damage experience to be considered will consist of:
Number, extent, location and frequency of cracks
Location of buckles.
This information may be found in the survey reports and/or the Owner's files, including theresults of the Owner's own inspections. The defects are to be analyzed, noted and marked on
sketches.
In addition, general experience is to be utilized. Also, reference is to be made to IACS's "Bulk
Carriers: Guidelines for Survey, Assessment and Repair," (Ref. 21) which contains acatalogue of typical damages and proposed repair methods for various structural details on
single skin bulk carriers. Reference should also be made to the TSCF's publication mentioned
in Ref. 32, which contains catalogues of typical damages and proposed repair methods fordouble hull oil tanker structural details which may to some extent be similar to structuraldetails in double skin bulk carriers. Such figures are to be used together with a review of themain drawings, in order to compare with the actual structure and search for similar details
that may be susceptible to damage. In particular, Chapter 3 of Ref. 32 deals with various
aspects specific to double hull tankers, such as stress concentration locations, misalignment
during construction, corrosion trends, fatigue considerations and areas requiring special
attention, while Chapter 4 of Ref. 32 addresses experience gained on structural defects indouble hulls (chemical tankers, OBO carriers, ore/oil carriers, gas carriers), which are also to
be considered in working out the survey planning.
The review of the main structural drawings, in addition to using the above-mentioned figures,is to include checking for typical design details where cracking has been experienced. The
factors contributing to damage are to be carefully considered.
The use of high tensile steel (HTS) is an important factor. Details showing good service
experience where ordinary, mild steel has been used may be more susceptible to damage
when HTS, and its higher associated stresses, are utilized. There is extensive and, in general,
good experience, with the use of HTS for longitudinal material in deck and bottom structures.
Experience in other locations, where the dynamic stresses may be higher, is less favourable,
e.g. side structures.
In this respect, stress calculations of typical and important components and details, inaccordance with the latest Rules or other relevant methods may prove useful and are to beconsidered.
The selected areas of the structure identified during this process should be recorded andmarked on the structural drawings to be included in the Survey Programme.

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Z10.5 Annex I

Z10.5(cont)

3.2.2

Corrosion

In order to evaluate relative corrosion risks, the following information is generally to beconsidered:-

Usage of Tanks, Holds and Spaces
Condition of Coatings
Cleaning Procedures
Previous Corrosion Damage
Ballast use and time for Cargo Holds
Risk of Corrosion in Cargo Holds and Ballast Tanks
Location of Ballast Tanks Adjacent to Heated Fuel Oil Tanks

Ref. 43 gives definitive examples which can be used for judging and describing coating
condition, using typical pictures of conditions.
The evaluation of corrosion risks is to be based on information in both Ref. 21 and Ref. 43, as
far as applicable to double skin bulk carriers, together with relevant information on the
anticipated condition of the ship as derived from the information collected in order to prepare
the Survey Programme and the age of the ship. The various holds, tanks and spaces are to
be listed with the corrosion risks nominated accordingly.
3.2.3

Locations for Close-up Survey and Thickness Measurement

On the basis of the table of corrosion risks and the evaluation of design experience, thelocations for initial close-up survey and thickness measurement (areas and sections) may be
nominated.
The sections subject to thickness measurement are to normally be nominated in tanks, holds
and spaces where corrosion risk is judged to be the highest.
The nomination of tanks, holds and spaces for close-up survey is to, initially, be based onhighest corrosion risk, and is to always include ballast tanks. The principle for the selection
should that the extent is increased by age or where information is insufficient or unreliable.

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Z10.5 Annex I

Z10.5(cont)

Input:
Drawings, Reports,
Acceptable Corrosion
Allowance

Collection of Information

Coating Condition
Usage of Tanks

Corrosion Risk

Design Related Risk
Analyse:Hull Damage
This Ship

Coating condition
Usage of Tanks

Corrosion
Damage This
Ship

Analyse:Hull Damage
for Similar Ships
Where Available

Corrosion
Damage Similar
Ship where
Available

Hull Damage:
General Experience
Present Areas
where Damage has
been found andRisks consideredhigh. Mark Sketches
or Drawings

Location for Thickness Measurement and Close-Up Survey

SurveyProgramme

Acceptance byClass & Owner

SurveyFigure 1: Technical Assessment & the Survey Planning Process
End of Annex I
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Z10.5 Annex II

ANNEX II

Z10.5
(cont)

RECOMMENDED PROCEDURES FOR THICKNESS MEASUREMENTS OF DOUBLE
SKIN BULK CARRIERS **Note: Annex II is recommendatory.

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Z10.5 Annex II

Z10.5(cont)CONTENTS

Sheet 1

Sheet 1-

Contents

Sheet 2-

Instructions

Sheet 3-General Particulars

Sheet 4-

Report TM1-DSBC for recording the thickness measurements of alldeck plating, all bottom shell plating and side shell plating

Sheet 5-

Report TM2-DSBC (i) for recording the thickness measurement ofshell and deck plating at transverse sections - strength deck andsheerstrake plating

Sheet 6-

Report TM2-DSBC (ii) for recording the thickness measurement ofshell and deck plating at transverse sections - shell plating

Sheet 7-

Report TM3-DSBC for recording the thickness measurement of
longitudinal members at transverse sections (including double hull
structure)

Sheet 8-

Report TM4-DSBC for recording the thickness measurement oftransverse structural members (including common frames, web frames
and transverse bulkheads in double hull tanks)

Sheet 9-

Report TM5-DSBC for recording the thickness measurement of W.T.
transverse bulkheads in cargo holds

Sheet 10-

Report TM6-DSBC for recording the thickness measurement of
miscellaneous structural members

Sheet 11-

Typical transverse section of a double skin bulk carrier.
The diagram includes details of the items to be measured and thereport forms to be used.

Sheet 12-

Typical transverse section of an ore carrier.
The diagram includes details of the items to be measured and thereport forms to be used.

Sheet 13-

Thickness Measurement - Double Skin Bulk Carriers
Transverse section outline. The diagram may be used for those ships
where the diagrams on sheet 11 and 12 are not suitable.

Sheet 14-

Thickness Measurement - Ore Carriers
Areas subject to close-up surveys and thickness measurements areas (A) to (E) as defined in Table I of the UR Z10.5.

REPORTSGUIDANCE

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Z10.5 Annex II

Z10.5(cont)INSTRUCTION

Sheet 2

Recommended Procedures for Thickness Measurements of Double Skin Bulk Carriers
1.

This document is to be used for recording thickness measurements as required by
IACS Unified Requirement Z10.5.

2.

Reporting forms TM1-DSBC, TM2-DSBC, TM3-DSBC, TM4-DSBC, TM5-DSBC and
TM6-DSBC (sheets 4-10) are to be used for recording thickness measurements andthe maximum allowable diminution should be stated.
The maximum allowable diminution could be stated in an attached document.

3.

The remaining sheets 11-14 are guidance diagrams and notes relating to the reporting
forms and the procedure for the thickness measurements.

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Z10.5 Annex II

Z10.5(cont)

GENERAL PARTICULARS

Sheet 3Ship’s name:IMO Number:Class Identification number:Port of registry:Gross tons:Deadweight:Date of build:Classification Society:-

Name of Firm performing the thickness measurement:Thickness measurement firm certified by:Certificate No. :Certificate valid from..................to................
Place of measurement:First date of measurement:Last date of measurement:Special survey/intermediate survey due:-*
Details of measurement equipment:Qualification of operator:Report Number:-Consisting of......Sheets

Name of operator:-........................

Name of surveyor:-........................

Signature of operator:-.

.......................

Signature of surveyor:-........................

Firm official stamp:-........................

Classification Society
Official Stamp:-........................

* Delete as appropriate

Page 75 of 127

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Z10.5 Annex II

Z10.5(cont)

TM1-DSBC

Report on THICKNESS MEASUREMENT of ALL DECK PLATING, ALL BOTTOM SHELL PLATING
and SIDE SHELL PLATING*(* - delete as appropriate)

Ship’s name.........................
STRAKEPOSITIONPLATE
POSITION
12th forward
11th
10th
9th
8th
7th
6th
5th
4th
3rd
2nd
1st
Amidships
1st aft
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th

No.
or
Letter

Org.
Thk.
mm

Class Identity No. .........................

Report No. .........................

GaugedForward Reading
Diminution P
Diminution S

GaugedAft Reading
Diminution P

Diminution S

P

mm

P

mm

mm

S

%

mm

%

Operators Signature.............................................

Sheet 4S%%

Mean Diminution%
P

S

Maximum
Allowable
Diminutionmm

NOTES – See Reverse

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Z10.5 Annex II

Z10.5

NOTES TO REPORT TM1-DSBC(cont)

1.

2.

This report is to be used for recording the thickness measurement of:1.1

All strength deck plating within cargo length area.

1.2

All keel, bottom shell plating and bilge plating within the cargo length area.

1.3

Side shell plating including selected wind and water strakes outside cargo
length area.

1.4

All wind and water strakes within cargo length area.

The strake position is to be cleared indicates as follows:2.1

For strength deck indicate the number of the strake of plating inboard from thestringer plate.

2.2

For bottom plating indicate the number of the strake of plating outboard fromthe keel plate.

2.3

For side shell plating give number of the strake of plating sheerstrake andletter as shown on shell expansion.

3.

Only the deck plating strakes outside line of openings are to be recorded.

4.

Measurements are to be taken at the forward and aft areas of all plates and whereplates cross ballast/cargo tank boundaries separate measurements for the area of
plating in way of each type of tank are to be recorded.

5.

The single measurements recorded are to represent the average of multiple
measurements.

6.

The maximum allowable diminution could be stated in an attached document.

Page 77 of 127

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Z10.5 Annex II

Z10.5(cont)

TM2-DSBC (i)Report on THICKNESS MEASUREMENT OF SHELL AND DECK PLATING at transverse sections(one, two or three transverse sections)

Ship’s name.........................

Class Identity No. .........................

Sheet 5

Report No. .........................

STRENGTH DECK AND SHEERSTRAKE PLATINGFIRST TRANSVERSE SECTION AT FRAME NUMBER
STRAKEPOSITION
StringerPlate
1st strake
inboard
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th
13th
14th
centrestrakesheerstrakeTOPSIDE
TOTAL

No.
or
LetterSECOND TRANSVERSE SECTION AT FRAME NUMBER

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

%

%

No.
or
Letter

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

Operators Signature.............................................

%%THIRD TRANSVERSE SECTION AT FRAME NUMBER
No.
or
Letter

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

%

NOTES – See Reverse

Page 78 of 127

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Z10.5 Annex II

Z10.5

NOTES TO REPORT TM2-DSBC (i)(cont)

1.

This report is to be used for recording the thickness measurement of:Strength deck plating and sheerstrake plating transverse sections:One, two or three sections within the cargo length area, comprising thestructural items (0), (1) and (2) as shown on the diagrams of typical transverse
sections illustrated on sheets 11, 12 and 13 of this document.

2.

Only the deck plating strakes outside line of hatch openings are to be recorded.

3.

The top side area comprises deck plating, stringer plate and sheerstrake (including
rounded gunwales).

4.

The exact frame station of measurement is to be stated.

5.

The single measurements recorded are to represent the average of multiple
measurements.

6.

The maximum allowable diminution could be stated in an attached document.

Page 79 of 127

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Z10.5 Annex II

Z10.5(cont)

TM2-DSBC (ii)

Report on THICKNESS MEASUREMENT OF SHELL AND DECK PLATING at transverse sections(one, two or three transverse sections)

Ship’s name.........................

Class Identity No. .........................

Sheet 6

Report No. .........................

SHELL PLATINGFIRST TRANSVERSE SECTION AT FRAME NUMBER
STRAKEPOSITION
1st below
sheer
strake
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th
13th
14th
15th
16th
17th
18th
19th
20th
keel strake
BOTTOM
TOTAL

No.
or
LetterSECOND TRANSVERSE SECTION AT FRAME NUMBER

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

%

%

No.
or
Letter

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

Operators Signature.............................................

%%THIRD TRANSVERSE SECTION AT FRAME NUMBER
No.
or
Letter

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

%

NOTES – See Reverse

Page 80 of 127

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Z10.5 Annex II

Z10.5(cont)NOTES TO REPORT TM2-DSBC (ii)1.

This report is to be used for recording the thickness measurement of:Shell plating at transverse sections:
One, two or three sections within the cargo length area, comprising the structural
items (3), (4), (5) and (6) as shown on the diagrams of typical transverse sections
illustrated on sheets 11, 12 and 13 of this document.

2.

The bottom area comprises keel, bottom and bilge plating.

3.

The exact frame station of measurement is to be stated.

4.

The single measurements recorded are to represent the average of multiple
measurements.

5.

The maximum allowable diminution could be stated in an attached document.

Page 81 of 127

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Z10.5 Annex II

Z10.5(cont)

TM3-DSBC

Report on THICKNESS MEASUREMENT OF LONGITUDINAL MEMBERS at transverse sections(one, two or three transverse sections)

Ship’s name.........................

Class Identity No. .........................

FIRST TRANSVERSE SECTION AT FRAME NUMBER
STRUCTURAL
MEMBER

Item
No.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

%

Report No. ........................

SECOND TRANSVERSE SECTION AT FRAME NUMBER

Org.
Thk.

%

Item
No.

Sheet 7

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

Operators Signature.............................................

%%THIRD TRANSVERSE SECTION AT FRAME NUMBER
Item
No.

Org.
Thk.

Max.
Alwb.
Dim.

GaugedDiminution
P

Diminution
S

mm

mm

P

mm

mm

S

%

NOTES – See Reverse

Page 82 of 127

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Z10.5 Annex II

Z10.5(cont)NOTES TO REPORT TM3-DSBC
1.

This report is to be used for recording the thickness measurement of:Longitudinal Members at transverse sections:Two, or three sections within the cargo length area comprising the appropriate
structural items (10) to (25) as shown on diagrams of typical transverse
sections illustrated on sheets 11, 12 and 13 of this document.

2.

The exact frame station of measurement is to be stated.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The maximum allowable diminution could be stated in an attached document.

Page 83 of 127

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Z10.5 Annex II

Z10.5(cont)

TM4-DSBC

Report on THICKNESS MEASUREMENT OF TRANSVERSE STRUCTURAL MEMBERS
In the double bottom, hopper side and topside water ballast tanks

Ship’s name.........................

Class Identity No. .........................

Sheet 8

Report No. ........................

TANK DESCRIPTION:
LOCATION OF STRUCTURE:
STRUCTURAL MEMBER

ITEM

Original
Thickness
mm

Max.
Alwb.
Dim.
mm

GaugedP

Operators Signature.............................................

Diminution
P
S

mm

Diminution
S
%

mm

%

NOTES – See Reverse

Page 84 of 127

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Z10.5 Annex II

Z10.5(cont)NOTES TO REPORT TM4-DSBC
1.

This report is to be used for recording the thickness measurement of:Transverse structural members, comprising the appropriate structural items (30) to(34) as shown on diagrams of typical transverse sections illustrated on sheets 11, 12
and 13 of this document.

2.

Guidance for areas of measurements is indicated on sheet 14 of this document.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The maximum allowable diminution could be stated in an attached document.

Page 85 of 127

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Z10.5 Annex II

Z10.5(cont)

TM5-DSBC

Report on THICKNESS OF WATERTIGHT TRANSVERSE BULKHEADS IN CARGO HOLDS

Ship’s name.........................

Class Identity No. .........................

LOCATION OF STRUCTURE:

Sheet 9

Report No. ........................
FRAME NO.:STRUCTURAL COMPONENT (PLATING/STIFFENER)
Original
Thickness
mm

Max.
Alwb.
Dim.
mm

GaugedPort

Operators Signature.............................................

Starboard

Diminution
P
mm

Diminution
S
%

mm

%

NOTES – See Reverse

Page 86 of 127

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Z10.5 Annex II

Z10.5(cont)NOTES TO REPORT TM5-DSBC
1.

This report form is to be used for recording the thickness measurement of:W.T. transverse bulkheads in cargo holds

2.

Guidance for areas of measurements is indicated on sheet 14 of this document.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The maximum allowable diminution could be stated in an attached document.

Page 87 of 127

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Z10.5 Annex II

Z10.5(cont)

TM6-DSBC

Report on THICKNESS MEASUREMENT OF MISCELLANEOUS STRUCTURAL MEMBERS

Ship’s name.........................

Class Identity No. .........................

Sheet 10
Report No. ........................

STRUCTURAL MEMBER:

SKETCHLOCATION OF STRUCTURE:
Description

Org.
Thk.
mm

Max.
Alwb.
Dim.
mm

GaugedDiminution
P

Diminution
S

P

mm

mm

S

%

Operators Signature.............................................

%NOTES – See Reverse

Page 88 of 127

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Z10.5 Annex II

Z10.5

NOTES TO REPORT TM6-DSBC(cont)

1.

This report is to be used for recording the thickness measurement of:Miscellaneous structural members including the structural items (40), (41) and(42) as shown on diagrams of typical transverse sections illustrated on sheets
11, 12 and 13 of this document.

2.

Guidance for areas of measurement is indicated on sheet 14 of this document.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The maximum allowable diminution could be stated in an attached document.

Page 89 of 127

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Z10.5 Annex II
Sheet 11

Z10.5
(cont)

1.
2.
3.
4.
5.
6.
7.

Report on TM2-DSBC(i) & (ii)Strength deck plating
Stringer plate
Sheerstrake
Side shell plating
Bilge plating
Bottom shell plating
Keel plate

23.
25.
34.
-

Report on TM3-DSBC
8.
9.
10.
11.
12.
13.
14.
15.
16.

Deck longitudinals
Deck girders
Sheerstrake longitudinals
Topside tank sloping plate
Topside tank sloping plate longitudinals
Bottom longitudinals
Bottom girders
Bilge longitudinals
Side shell longitudinals, if any

Report on TM4-DSBC
Double bottom tank floors
Hopper side tank transverses
Transverse web frame
Topside tank transverses

28.
-

17.
18.
19.
20.
31.
-

Inner bottom plating
Inner bottom longitudinals
Hopper plating
Hopper longitudinals
Inner side plating
Inner side longitudinals, if any
Horizontal girders in wing ballast tanks

Report on TM6-DSBC
Hatch coamings
Deck plating between hatches
Hatch covers

Page 90 of 127

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Z10.5 Annex II
Sheet 12Z10.5
(cont)

1.
2.
3.
4.
5.
6.
7.

Report on TM2-DSBC(i) & (ii)Strength deck plating
Stringer plate
Sheerstrake
Side shell plating
Bilge plating
Bottom shell plating
Keel plate

8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.

Report on TM3-DSBC
Deck longitudinals
Deck girders
Sheerstrake longitudinals
Longitudinal bulkhead top strake
Bottom longitudinals
Bottom girders
Bilge longitudinals
Longitudinal bulkhead lower strake
Side shell longitudinals
Longitudinal bulkhead plating (remainder)
Longitudinal bulkhead longitudinals
Inner bottom plating
Inner bottom longitudinals

25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.

36.
37.
38.
39.
40.

Page 91 of 127

Report on TM4-DSBC
Deck transverse centre tank
Bottom transverse centre tank
Deck transverse wing tank
Side shell vertical web
Longitudinal bulkhead vertical web
Bottom transverse wing tank
StrutsTransverse web face plate
D.B. Floors

Report on TM6-DSBC
Hatch coamings
Deck plating between hatches
Hatch covers

IACS Req. 2003/Rev.20 2023

Z10.5 Annex II

Z10.5

Sheet 13(cont)

1.
2.
3.
4.
5.
6.
7.

Report on TM2-DSBC(i) & (ii)Strength deck plating
Stringer plate
Sheerstrake
Side shell plating
Bilge plating
Bottom shell plating
Keel plate

23.
25.
34.
-

Report on TM3-DSBC
8.
9.
10.
11.
12.
13.
14.
15.
16.

Deck longitudinals
Deck girders
Sheerstrake longitudinals
Topside tank sloping plate
Topside tank sloping plate longitudinals
Bottom longitudinals
Bottom girders
Bilge longitudinals
Side shell longitudinals, if any

Report on TM4-DSBC
Double bottom tank floors
Hopper side tank transverses
Transverse web frame
Topside tank transverses

28.
-

17.
18.
19.
20.
31.
-

Inner bottom plating
Inner bottom longitudinals
Hopper plating
Hopper longitudinals
Inner side plating
Inner side longitudinals, if any
Horizontal girders in wing ballast tanks

Report on TM6-DSBC
Hatch coamings
Deck plating between hatches
Hatch covers

Page 92 of 127

IACS Req. 2003/Rev.20 2023

Z10.5 Annex II

Z10.5

Sheet 14(cont)

Page 93 of 127

IACS Req. 2003/Rev.20 2023

Z10.5 Annex II (CSR)

Z10.5(cont)

ANNEX II (CSR)
IACS RECOMMENDED PROCEDURES FOR THICKNESS MEASUREMENTS OF
DOUBLE SKIN BULK CARRIERS BUILT UNDER IACS COMMON STRUCTURAL RULES**
Note: Annex II (CSR) is recommendatory.

Page 94 of 127

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Z10.5 Annex II (CSR)

Z10.5(cont)CONTENTS

Sheet 1

Sheet 1-

Contents

Sheet 2-

Instructions

Sheet 3-General particulars

Sheet 4-

Report TM1-DSBC(CSR) for recording the thickness measurement of
all deck plating, all bottom plating and side shell plating

Sheet 5-

Report TM2-DSBC(CSR) (i) for recording the thickness measurementof shell and deck plating at transverse sections - strength deck andsheerstrake plating

Sheet 6-

Report TM2-DSBC(CSR) (ii) for recording the thickness measurementof shell plating at transverse sections

Sheet 7-

Report TM3-DSBC(CSR) for recording the thickness measurement of
longitudinal members at transverse sections (including double hull
structure)

Sheet 8-

Report TM4-DSBC(CSR) for recording the thickness measurement oftransverse structural members (including common frames, web frames
and transverse bulkheads in double hull tanks)

Sheet 9-

Report TM5-DSBC(CSR) for recording the thickness measurement ofW.T. transverse bulkheads in cargo holds

Sheet 10-

Report TM6-DSBC(CSR) for recording the thickness measurement of
miscellaneous structural members

Sheet 11-

Typical transverse section of a double skin bulk carrier.
The diagram includes details of the items to be measured and thereport forms to be used.

Sheet 12-

Thickness Measurement - Double Skin Bulk Carriers
Transverse section outline. This diagram may be used for those ships
where the diagram on sheet 11 is not suitable.

Sheet 13-

Sketches of double skin bulk carrier showing typical areas for thickness
measurement of structural members and transverse bulkheads inassociation with close-up survey requirements. – areas (A) to (E) as
defined in Table I of the UR Z10.5.

REPORTSGUIDANCE

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Z10.5 Annex II (CSR)

Z10.5

INSTRUCTIONS(cont)

Sheet 2

IACS Recommended Procedures for Thickness Measurements of Double Skin Bulk
Carriers Built under IACS Common Structural Rules
1.

This document is to be used for recording thickness measurements of double skinbulk carriers built under IACS Common Structural Rules as required by the IACS
Unified Requirement Z10.5.

2.

Reporting forms TM1-DSBC(CSR), TM2-DSBC(CSR) (i) and (ii), TM3-DSBC(CSR),
TM4-DSBC(CSR), TM5-DSBC(CSR) and TM6-DSBC(CSR) (sheets 4-10) are to be
used for recording thickness measurements. The as-built thickness and the voluntary
thickness addition and renewal thickness (minimum allowable thickness) are to bestated in the said forms.

3.

The remaining sheets 11-13 are guidance diagrams and notes relating to the reporting
forms and the procedure for the thickness measurement.

Page 96 of 127

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Z10.5 Annex II (CSR)

Z10.5(cont)

Sheet 3

GENERAL PARTICULARS
Ships name:IMO number:Class identity number:Port of registry:Gross tons:Deadweight:Date of build:Classification Society:Name of Firm performing thickness measurement:Thickness measurement firm certified by:Certificate No:Certificate valid from..................to................
Place of measurement:First date of measurement:Last date of measurement:Special survey/intermediate survey due:-*
Details of measurement equipment:Qualification of operators:Report Number:-consisting of......Sheets

Name of operator:-........................

Name of surveyor:-........................

Signature of operator:-.

.......................

Signature of surveyor:-........................

Firm official stamp:-

Classification Society
Official Stamp:-* Delete as appropriate

Page 97 of 127

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Z10.5 Annex II (CSR)

Z10.5 TM1-DSBC(CSR)(cont)

Report on THICKNESS MEASUREMENT of ALL DECK PLATING, ALL BOTTOM PLATING
or SIDE SHELL PLATING*(* - delete as appropriate)

Ship’s name.........................
STRAKEPOSITIONPLATE
POSITION
12th forward
11th
10th
9th
8th
7th
6th
5th
4th
3rd
2nd
1st
Amidships
1st aft
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th

No.
or
LetterAs Built
Thk.
mm

Class Identity No.........................

Voluntary
Thickness
Additionmm

RenewalThicknessmm(a)Forward Reading
Gauged Thk.
Remaining Corr.
mm
Addition, mm(b1)(c1)=(b1)-(a)P
S
PS

Operators Signature.............................................

Sheet 4

Report No.........................

Gauged Thk.
mm
(b2)
P
S

Aft Reading
Remaining Corr.
Addition, mm(c2)=(b2)-(a)P
S

Mean Remaining Corr.
Addition, mm[(c1)+(c2)]/2
PS

NOTES – See Reverse

Page 98 of 127

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Z10.5 Annex II (CSR)

Z10.5

NOTES TO REPORT TM1-DSBC(CSR)(cont)

1.

2.

This report is to be used for recording the thickness measurement of:1.1

All strength deck plating within cargo length area.

1.2

All keel, bottom shell plating and bilge plating within the cargo length area.

1.3

Side shell plating including selected wind and water strakes outside the cargo
length area.

1.4

All wind and water strakes within the cargo length area.

The strake position is to be cleared indicated as follows:2.1

For strength deck indicate the number of the strake of plating inboard from thestringer plate.

2.2

For bottom plating indicate the number of the strake of plating outboard fromthe keel plate.

2.3

For side shell plating give number of the strake of plating sheerstrake andletter as shown on shell expansion.

3.

Only the deck plating strakes outside line of openings are to be recorded.

4.

Measurements are to be taken at the forward and aft areas of all plates and the single
measurements recorded are to represent the average of multiple measurements.

5.

The remaining corrosion addition is to be recorded with result of gauged
thickness minus renewal thickness. If the result is negative, the structure in
way shall be renewed, and the mark “R” is to be indicated in the right-handcolumn. If the result is between 0 and 0.5 mm (0 included), the structure in
way shall be additional gauged, and the mark “S” is to be indicated in the righthand column.

Page 99 of 127

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Z10.5 Annex II (CSR)
on THICKNESS MEASUREMENT OF SHELL AND DECK PLATING
Z10.5 TM2-DSBC(CSR) (i) Report(one, two or three transverse sections)

Sheet 5

(cont)

Ship’s name.........................

Class Identity No.........................

Report No.........................

STRENGTH DECK AND SHEERSTRAKE PLATINGFIRST TRANSVERSE SECTION AT FRAME NUMBER
STRAKEPOSITION
StringerPlate
1st strake
inboard
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th
13th
14th
centrestrakesheerstrakeTOPSIDE
TOTAL

No.
or
Letter

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Remaining Corr.
Addition, mm

P(b)-(a)S

SECOND TRANSVERSE SECTION AT FRAME NUMBER
No.
or
Letter

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Operators Signature.............................................

Remaining Corr.
Addition, mm

P(b)-(a)S

THIRD TRANSVERSE SECTION AT FRAME NUMBER
No.
or
Letter

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Remaining Corr.
Addition, mm

P(b)-(a)NOTES – See Reverse

Page 100 of 127

IACS Req. 2003/Rev.20 2023

S

Z10.5 Annex II (CSR)

Z10.5

NOTES TO REPORT TM2-DSBC(CSR) (i)(cont)

1.

This report is to be used for recording the thickness measurement of:Strength deck plating and sheerstrake plating transverse sections:One, two or three sections within the cargo length area, comprising of thestructural items (1), (2) and (3) as shown on the diagram of typical transverse
sections illustrated on sheets 11 and 12 of this document.

2.

Only the deck plating strakes outside the line of openings are to be recorded.

3.

The topside area comprises deck plating, stringer plate and sheerstrake (including
rounded gunwales).

4.

The exact frame station of measurement is to be stated.

5.

The single measurements recorded are to represent the average of multiple
measurements.

6.

The remaining corrosion addition is to be recorded with result of gauged thickness
minus renewal thickness. If the result is negative, the structure in way shall berenewed, and the mark “R” is to be indicated in the right-hand column. If the result is
between 0 and 0.5 mm (0 included), the structure in way shall be additional gauged,
and the mark “S” is to be indicated in the right-hand column.

Page 101 of 127

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Z10.5 Annex II (CSR)
on THICKNESS MEASUREMENT OF SHELL PLATING
Z10.5 TM2-DSBC(CSR) (ii) Report(one, two or three transverse sections)

Sheet 6

(cont)

Ship’s name.........................

Class Identity No.........................

Report No.........................

SHELL PLATINGFIRST TRANSVERSE SECTION AT FRAME NUMBER
STRAKEPOSITION
1st below
sheer
strake
2nd
3rd
4th
5th
6th
7th
8th
9th
10th
11th
12th
13th
14th
15th
16th
17th
18th
19th
20th
Keel strake
BOTTOM
TOTAL

No.
or
Letter

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Remaining Corr.
Addition, mm

P(b)-(a)S

SECOND TRANSVERSE SECTION AT FRAME NUMBER
No.
or
Letter

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Operators Signature.............................................

Remaining Corr.
Addition, mm

P(b)-(a)S

THIRD TRANSVERSE SECTION AT FRAME NUMBER
No.
or
Letter

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Remaining Corr.
Addition, mm

P(b)-(a)NOTES – See Reverse

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S

Z10.5 Annex II (CSR)

Z10.5(cont)NOTES TO REPORT TM2-DSBC(CSR) (ii)1.

This report is to be used for recording the thickness measurement of:Shell plating at transverse sections:One, two or three sections within the cargo length area, comprising of thestructural items (4), (5), (6) and (7) as shown on the diagram of typical transverse
sections illustrated on sheets 11 and 12 of this document.

2.

The bottom area comprises keel, bottom and bilge plating.

3.

The exact frame station of measurement is to be stated.

4.

The single measurements recorded are to represent the average of multiple
measurements.

5.

The remaining corrosion addition is to be recorded with result of gauged thickness
minus renewal thickness. If the result is negative, the structure in way shall be renewed,
and the mark “R” is to be indicated in the right-hand column. If the result is between 0
and 0.5 mm (0 included), the structure in way shall be additional gauged, and the mark“S” is to be indicated in the right-hand column.

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Z10.5 Annex II (CSR)

Z10.5 TM3-DSBC(CSR)

Report on THICKNESS MEASUREMENT OF LONGITUDINAL MEMBERS(one, two or three transverse sections)(cont)

Ship’s name.........................
FIRST TRANSVERSE SECTION AT FRAME NUMBER
STRUCTURAL
MEMBER

Item
No.

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Remaining Corr.
Addition, mm

P(b)-(a)S

Sheet 7

Class Identity No.........................

Report No........................

SECOND TRANSVERSE SECTION AT FRAME NUMBER

THIRD TRANSVERSE SECTION AT FRAME NUMBER

Item
No.

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Operators Signature.............................................

Remaining Corr.
Addition, mm

P(b)-(a)

S

Item
No.

As
Built
Thk.
mm

Vol.
Thk.
Add.
mm

Ren.
Thk.
mm
(a)

Gauged
Thk.
mm
(b)

P

S

Remaining Corr.
Addition, mm

P(b)-(a)NOTES – See Reverse

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S

Z10.5 Annex II (CSR)

Z10.5

NOTES TO REPORT TM3-DSBC(CSR)(cont)

1.

This report is to be used for recording the thickness measurement of:Longitudinal Members at transverse sections:One, two or three sections within the cargo length area, comprising of theappropriate structural items (8) to (20) and (31) as shown on diagram of typicaltransverse sections illustrated on sheets 11 and 12 of this document.

2.

The exact frame station of measurement is to be stated.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The remaining corrosion addition is to be recorded with result of gauged thickness
minus renewal thickness. If the result is negative, the structure in way shall berenewed, and the mark “R” is to be indicated in the right-hand column. If the result is
between 0 and 0.5 mm (0 included), the structure in way shall be additional gauged,
and the mark “S” is to be indicated in the right-hand column.

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Z10.5 Annex II (CSR)

Z10.5 TM4-DSBC(CSR)(cont)

Report on THICKNESS MEASUREMENT OF TRANSVERSE STRUCTURAL MEMBERS
In the double bottom, hopper side and topside water ballast tanks

Ship’s name.........................

Class Identity No.........................

Sheet 8

Report No........................

TANK DESCRIPTION:
LOCATION OF STRUCTURE
STRUCTURAL MEMBERITEM

As Built
Thicknessmm

Voluntary
Thickness
Additionmm

RenewalThicknessmm(a)Operators Signature.............................................

Gauged Thickness
mm
(b)

P

S

Remaining Corr. Additionmm(b)-(a)PS

NOTES – See Reverse

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Z10.5 Annex II (CSR)

Z10.5(cont)NOTES TO REPORT TM4-DSBC(CSR)
1.

This report is to be used for recording the thickness measurement of:Transverse structural members, comprising of the appropriate structural items (23) to(25) and (34) as shown on diagram of typical transverse section, illustrated on sheets
11 and 12 of this document.

2.

Guidance for areas if measurement is indicated on the diagrams shown on sheet 13of this document.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The remaining corrosion addition is to be recorded with result of gauged thickness
minus renewal thickness. If the result is negative, the structure in way shall berenewed, and the mark “R” is to be indicated in the right-hand column. If the result is
between 0 and 0.5 mm (0 included), the structure in way shall be additional gauged,
and the mark “S” is to be indicated in the right-hand column.

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Z10.5 Annex II (CSR)

Z10.5 TM5-DSBC(CSR)

Report on THICKNESS OF CARGO HOLD TRANSVERSE BULKHEADS

Sheet 9(cont)

Ship’s name.........................

Class Identity No.........................

Report No........................

HOLD DESCRIPTION:
LOCATION OF STRUCTURE:
STRUCTURAL COMPONENT(PLATING/STIFFENER)

FRAME NO.:As Built
Thicknessmm

Voluntary
Thickness
Additionmm

RenewalThicknessmm(a)Operators Signature.............................................

Gauged Thickness
mm
(b)

P

S

Remaining Corr. Additionmm(b)-(a)PS

NOTES – See Reverse

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Z10.5 Annex II (CSR)

Z10.5(cont)NOTES TO REPORT TM5-DSBC(CSR)
1.

This report form is to be used for recording the thickness measurement of:W.T. transverse bulkheads in cargo holds

2.

Guidance for areas of measurement is indicated on the diagrams shown on sheet 13of this document.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The remaining corrosion addition is to be recorded with result of gauged thickness
minus renewal thickness. If the result is negative, the structure in way shall berenewed, and the mark “R” is to be indicated in the right-hand column. If the result is
between 0 and 0.5 mm (0 included), the structure in way shall be additional gauged,
and the mark “S” is to be indicated in the right-hand column.

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Z10.5 Annex II (CSR)

Z10.5 TM6-DSBC(CSR)

Report on THICKNESS MEASUREMENT OF MISCELLANEOUS STRUCTURAL MEMBERS

Sheet 10(cont)

Ship’s name.........................

Class Identity No.........................

Report No........................

STRUCTURAL MEMBER:

SKETCHLOCATION OF STRUCTURE:
Description

As
Built
Thk.
mm

Voluntary
Thickness
Additionmm

Renewal Gauged Thickness
Thickness
mm
mm
(b)
(a)

P

S

Remaining Corr. Additionmm(b)-(a)P

Operators Signature.............................................

SNOTES – See Reverse

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Z10.5 Annex II (CSR)

Z10.5(cont)NOTES TO REPORT TM6-DSBC(CSR)
1.

This report is to be used for recording the thickness measurement of:Miscellaneous structural members including the structural items (28) as shownon diagram of typical transverse section illustrated on sheets 11 and 12 of thisdocument.

2.

Guidance for areas of measurement is indicated on sheet 13 of this document.

3.

The single measurements recorded are to represent the average of multiple
measurements.

4.

The remaining corrosion addition is to be recorded with result of gauged thickness
minus renewal thickness. If the result is negative, the structure in way shall berenewed, and the mark “R” is to be indicated in the right-hand column. If the result is
between 0 and 0.5 mm (0 included), the structure in way shall be additional gauged,
and the mark “S” is to be indicated in the right-hand column.

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Z10.5 Annex II (CSR)

Z10.5

Sheet 11
Thickness Measurement - Double Skin Bulk Carriers(cont)

Typical transverse section of a double skin bulk carrier with indication of longitudinal andtransverse members

Report on TM2-DSBC(CSR)(i) & (ii)1.
Strength deck plating
2.
Stringer plate3.
Sheerstrake
4.
Side shell plating
5.
Bilge plating
6.
Bottom plating
7.
Keel plate

23.
24.
25.
34.
-

Report on TM3-DSBC(CSR)
8.
9.
10.
11.
12.
13.
14.
15.
16.

Deck longitudinals
Deck girders
Sheerstrake longitudinals
Topside tank sloping plate
Topside tank sloping plate longitudinals
Bottom longitudinals
Bottom girders
Bilge longitudinals
Side shell longitudinals, if any

Report on TM4-DSBC(CSR)
Double bottom tank floors
Topside tank transverses
Hopper side tank transverses
Transverse web frame
Ordinary transverse frame indouble skin tank

28.
-

17.
18.
19.
20.
31.
-

Inner bottom plating
Inner bottom longitudinals
Hopper plating
Hopper longitudinals
Inner side plating
Inner side longitudinals, if any
Horizontal girders in wing ballast tanks

Report on TM6-DSBC(CSR)
Hatch coamings
Deck plating between hatches
Hatch covers

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Z10.5 Annex II (CSR)

Z10.5(cont)

Thickness Measurement - Double Skin Bulk Carriers

Sheet 12

Transverse section outline: This diagram may be used for those ships where the diagram on
sheet 11 is not suitable

Report on TM2-DSBC(CSR)(i) & (ii)1.
Strength deck plating
2.
Stringer plate3.
Sheerstrake
4.
Side shell plating
5.
Bilge plating
6.
Bottom plating
7.
Keel plate

23.
24.
25.
34.
-

Report on TM3-DSBC(CSR)
8.
9.
10.
11.
12.
13.
14.
15.
16.

Deck longitudinal
Deck girders
Sheerstrake longitudinals
Topside tank sloping plating
Topside tank sloping plating longitudinal
Bottom longitudinals
Bottom girders
Bilge longitudinals
Side shell longitudinals, if any

Report on TM4-DSBC(CSR)
Double bottom tank floors
Topside tank transverses
Hopper side tank transverses
Transverse web frame
Ordinary transverse frame indouble skin tank

28.
-

17.
18.
19.
20.
31.
-

Inner bottom plating
Inner bottom longitudinals
Hopper plating
Hopper longitudinals
Inner side plating
Inner side longitudinals, if any
Horizontal girders in wing ballast tanks

Report on TM6-DSBC(CSR)
Hatch coamings
Deck plating between hatches
Hatch covers

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Z10.5 Annex II (CSR)

Z10.5

Close-up Survey and Thickness Measurement Areas(cont)

Sheet 13

Typical transverse section
Areas A and D

Thickness to be reported on TM3-DSBC(CSR), TM4DSBC(CSR),TM6-DSBC(CSR) as appropriate

A cargo hold, transverse bulkhead
Area C

Typical areas of deck plating inside lineof hatch openings between cargo hold hatches

Thickness to be reported on TM5-DSBC(CSR)

Area E

Thickness to be reported on TM6-DSBC(CSR)

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Z10.5 Annex II (CSR)

Z10.5(cont)

Framing in double-side tanks
Area (B)

Ordinary transverse frame in double skin tankOrdinary longitudinal structure in double skin tankThickness to be reported on TM4-DSBC(CSR)

End ofAnnex II

End of Annex II

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Z10.5 Annex III

Z10.5(cont)

ANNEX III

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Z10.5 Annex IIIA

Z10.5

ANNEX IIIA

(cont)SURVEY PROGRAMME
Basic information and particulars

Name of ship:
IMO number:
Flag State:
Port of registry:
Gross tonnage:
Deadweight (metric tonnes):
Length between perpendiculars (m):Shipbuilder:
Hull number:Classification Society:
Class ID:
Date of build of the ship:
Owner:
Thickness measurement firm:

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Z10.5 Annex IIIA

Z10.5 1
(cont)

1.1

PreambleScope

1.1.1 The present survey programme covers the minimum extent of overall surveys, close-up
surveys, thickness measurements and pressure testing within the cargo length area, cargoholds, ballast tanks, including fore and aft peak tanks, required by UR Z10.5.
1.1.2 The arrangements and safety aspects of the survey are to be acceptable to theattending surveyor(s).
1.2Documentation

All documents used in the development of the survey programme are to be available onboard
during the survey as required by section 6.
2

Arrangement of cargo holds, tanks and spaces

This section of the survey programme is to provide information (either in the form of plans ortext) on the arrangement of cargo holds, tanks and spaces that fall within the scope of thesurvey.
3

List of cargo holds, tanks and spaces with information on their use, extent of
coatings and corrosion prevention system

This section of the survey programme is to indicate any changes relating to (and is to update)the information on the use of the holds and tanks of the ship, the extent of coatings and thecorrosion prevention system provided in the Survey Planning Questionnaire.
4

Conditions for survey

This section of the survey programme is to provide information on the conditions for survey,
e.g. information regarding cargo hold and tank cleaning, gas freeing, ventilation, lighting, etc.
5

Provisions and method of access to structures

This section of the survey programme is to indicate any changes relating to (and is to update)the information on the provisions and methods of access to structures provided in the Survey
Planning Questionnaire.
6

List of equipment for survey

This section of the survey programme is to identify and list the equipment that will be madeavailable for carrying out the survey and the required thickness measurements.
7

Survey requirements

7.1

Overall survey

This section of the survey programme is to identify and list the spaces that should undergo an
overall survey for this ship in accordance with 2.3.1.

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Z10.5 Annex IIIA

Z10.5 7.2
(cont)

Close-up survey

This section of the survey programme is to identify and list the hull structures that are toundergo a close-up survey for this ship in accordance with 2.3.2.
8Identification of tanks for tank testingThis section of the survey programme is to identify and list the cargo holds and tanks that are
to undergo tank testing for this ship in accordance with 2.5.
9Identification of areas and sections for thickness measurements

This section of the survey programme is to identify and list the areas and sections where
thickness measurements are to be taken in accordance with 2.4.1.
10

Minimum thickness of hull structures

This section of the survey programme is to specify the minimum thickness for hull structuresof this ship that are subject to UR Z10.5 (indicate either (a) or preferably (b), if suchinformation is available):(a)

Determined from the attached wastage allowance table and the original thickness tothe hull structure plans of the ship;(b)

Given in the following table(s):Area or location

Deck
Plating
Longitudinals
Longitudinal girders
Cross deck plating
Cross deck stiffeners
BottomPlating
Longitudinals
Longitudinal girders
Inner bottom
Plating
Longitudinals
Longitudinal girders
Floors
Ship side in way of topside tanks
Plating
Longitudinals
Ship side in way of hopper side tanks
Plating
Longitudinals
Ship side in way of double hull tanks
Plating
Longitudinals or ordinary transverse frames

Original asbuilt
thickness(mm)

Page 119 of 127

Minimum
thickness(mm)

Substantial
corrosion
thickness(mm)

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Z10.5 Annex IIIA

Z10.5 Longitudinal stringers(cont)

Longitudinal bulkhead (inner side)
Plating
Longitudinals or ordinary transverse framesLongitudinal girders (if applicable)
Transverse bulkheads
Plating
Stiffeners (if applicable)
Upper stool plating
Upper stool stiffeners
Lower stool plating
Lower stool stiffeners
Transverse web frames in topside tanks
Plating
Flanges
Stiffeners
Transverse web frames in double hulltanks
Plating
Flanges
Stiffeners
Transverse web frames in hopper tanks
Plating
Flanges
Stiffeners
Hatch Covers
Plating
Stiffeners
Hatch Coamings
Plating
Stiffeners
Note: The wastage allowance tables are to be attached to the survey programme.
For vessels built under IACS Common Structural Rules, the renewal thickness of the hull
structure elements is indicated in the appropriate drawings.
11

Thickness measurement firmThis section of the survey programme is to identify changes, if any, relating to the informationon the thickness measurement firm provided in the Survey Planning Questionnaire.
12

Damage experience related to the ship

This section of the survey programme is to, using the tables provided below, provide detailsof the hull damages for at least the last three years in way of the cargo holds, ballast tanks
and void spaces within the cargo length area. These damages are subject to survey.

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Z10.5 Annex IIIA

Z10.5

Hull damages sorted by location for this ship(cont)

Cargo hold,tank or
space
number or
area

Possiblecause, if
known

Descriptionof thedamages

Location

RepairDate ofrepairHull damages for sister or similar ships (if available) in the case ofdesign related damage
Cargo hold,tank or
space
number or
area

13

Possiblecause, if
known

Descriptionof thedamages

Location

RepairDate ofrepairAreas identified with substantial corrosion from previous surveys

This section of the survey programme is to identify and list the areas of substantial corrosion
from previous surveys.
14

Critical structural areas and suspect areas

This section of the survey programme is to identify and list the critical structural areas andthe suspect areas, when such information is available.
15

Other relevant comments and information

This section of the survey programme is to provide any other comments and information
relevant to the survey.
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Z10.5 Annex IIIA

Z10.5 Appendices(cont)

Appendix 1 - List of plans
Paragraph 5.1.3 requires that main structural plans of cargo holds and ballast tanks (scantling
drawings), including information regarding use of high tensile steel (HTS) are to be available.
This Appendix of the survey programme is to identify and list the main structural plans which
form part of the survey programme.
Appendix 2 - Survey Planning Questionnaire
The Survey Planning Questionnaire (annex IIIB), which has been submitted by the owner, is
to be appended to the survey programme.
Appendix 3 - Other documentation
This part of the survey programme is to identify and list any other documentation that forms
part of the plan.
Prepared by the owner in co-operation with the Classification Society for compliance with
5.1.3:
Date:…………………………(name and signature of authorized owner’s representative)
Date:…………………………(name and signature of authorized representative of theClassification Society)

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Z10.5 Annex IIIB

Z10.5

ANNEX IIIB

(cont)SURVEY PLANNING QUESTIONNAIRE
1 The following information will enable the owner in co-operation with the Classification
Society to develop a Survey Programme complying with the requirements of UR Z10.5. It isessential that the owner provides, when completing the present questionnaire, up-to-date
information. The present questionnaire, when completed, shall provide all information andmaterial required by UR Z10.5.
Particulars
Ship’s name:
IMO number:
Flag State:
Port of registry:
Owner:Classification Society:
Class ID:
Gross tonnage:
Deadweight (metric tonnes):
Date of build:
Information on access provision for close-up surveys and thickness measurement
2 The owner is to indicate, in the table below, the means of access to the structures subject
to close-up survey and thickness measurement. A close-up survey is an examination where
the details of structural components are within the close visual inspection range of theattending surveyor, i.e. normally within reach of hand.

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Z10.5 Annex IIIB

Z10.5
(cont)

Hold/
Tank
No.

Structure

Permanent
Means ofAccessTemporarystaging

F.P.
A.P.
CARGO
HOLDS

Fore Peak
Aft PeakHatch side coamings
Topside sloping plate
Upper stool plating
Cross deck
Double side tankplating
Transverse bulkhead
Hopper tank platting
Lower stool plating
Tank top
TOPSIDE Underdeck structure
TANKS
Side shell & structure
Sloping plate &structure
Webs & bulkheads
HOPPER Hopper sloping plate
TANKS& structure
Side shell & structure
Bottom structure
Webs & bulkheads
DOUBLE Side shell & structure
SIDE
Inner skin & structure
SKIN
Webs & bulkheads
TANKS
Double bottom
structure
Upper stool internal
structure
Lower stool internal
structure
WING
Underdeck &TANKS
structure
OF ORE Side shell & structure
CARRIE Side shell verticalRS
web & structureLongitudinalbulkhead & structureLongitudinalbulkhead web &structure
Bottom plating &structure
Cross ties/stringers

Page 124 of 127

Rafts

Ladders

DirectaccessOther
means(pleasespecify)

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Z10.5 Annex IIIB

Z10.5
(cont)

History of bulk cargoes of a corrosive nature (e.g. high sulphur content)

Owner’s inspections
3 Using a format similar to that of the table below (which is given as an example), the owneris to provide details of the results of their inspections, for the last 3 years - in accordance with
UR Z10.5 - on all CARGO holds and BALLAST tanks and VOID spaces within the cargo area.
Tank/HoldNo.

Corrosion
protection(1)

Coating
extent(2)

Coating
condition(3)

Structural
deterioration(4)

Hold andtank history(5)

Cargo holds
Topside tanks
Hopper tanks
Double sideskin tanks
Doublebottom tanks
Upper stools
Lower stools
Wing tanks(ore carriers)
Fore peak
Aft peakMiscellaneous
other spaces:
Note: Indicate tanks which are used for oil/ballast
1)

HC=hard coating; SC=soft coating;SH=semihard coating; NP=no protection

2)

U=upper part; M=middle part;
L=lower part; C=complete

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Z10.5 Annex IIIB

Z10.5 3)
(cont)

G=good; F=fair; P=poor;
RC=recoated (during the last 3 years)

4)

N=no findings recorded; Y=findings recorded,
description of findings is to be attached to this questionnaire

5)

DR=Damage & Repair; L=Leakages;
CV= Conversion(Description to be attached to this questionnaire)

Name of owner’s representative:
Signature:
Date:

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Z10.5 Annex IIIB

Z10.5 Reports of Port State Control inspections(cont)

List the reports of Port State Control inspections containing hull structural related
deficiencies, relevant information on rectification of the deficiencies:

Safety Management System
List non-conformities related to hull maintenance, including the associated corrective
actions:

Name and address of the approved thickness measurement firm:

Annex III end
Document end
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