IACS Common Structural Rules Knowledge Centre

Bulker Q&As and CIs on the IACS CSR Knowledge Centre
KCID
No.

Ref.

Table
11.2.2 &323
Text
11/2.2.6.1

Table
11.2.2 &324
Text
11/2.2.6.1

Type

QuestionCI

337

3/6.10.4.7&
Question11/2.2.4.3

339

Ch11/2

454

Ch11/
Sec.2
Table 1

Question

CI

Topic

Date
completed

Attachment

Question/CI

Answer

2007/1/12

The fillet welds to apply for the connection of collar plates with ordinary
stiffener and with web of primary members is not defined clearly in Table 2 ofChapter 11, Section 2. Please clarify this matter?

The check of welding shear section attaching shell ordinary stiffeners toprimary member is effectively defined in Table 2 in Ch 11, Sec 2, considering
Hull area being "General", and connection of ordinary stiffener to cut-out in
way of primary supporting member, i.e. Category F2. Regarding the weldingof collar plates, it is covered by the same line of the Table. However, for abetter understanding, this line in the Table should be modified, replacing"ordinary stiffener" by "ordinary stiffener and collar plate, if any" and replacing"Cut-out web of primary supporting members" by "Web of primary members
and collar plates, if any".

2007/1/8

Two different requirements for welding thicknesses of side web frame in single The welding throats as defined on Fig 19 of Ch 3, Sec 6 are only to beside bulk carrier are indicated in CSR: - Ch3, Sec6, 8.3 Side frames fig 19.
applied. Consequently, Tab 2 in Ch 11, Sec 2 should be modified, for the hull
(URS12) - Ch11, Sec2 Welding Table 2 with Hull area side frame of single
area "Side frame of single side structure", connection of "side frame and end
side structure. Our understanding is that the maximum of both is to be
bracket" to "side shell plate" by repacing "F1" by "See Ch 3, Sec 2, Fig 19".
considered. Please confirm?
We will consider the editorial correction.

S18

2007/2/22

For the weld of corrugations and stool side plating to the stool top plate, only
full penetration is accepted in the requirement of Ch 3, Sec 6, 10.4.7. On theother hand, not only full penetration but deep penetration is accepted in therequirement of Ch 11, Sec 2, 2.4.3. It is considered that this requirement is
We will consider the editorial correction according to UR S18.
based on IACS UR 18.4.1(a), as follows:
Also Included in Corrigenda 5
The stool side plating is to be connected to the stool top plate and the inner
bottom plating by either full penetration or deep penetration welds. Therefore,
the requirement of Ch 3, Sec 6, 10.4.7 should be changed to be consistent
with Ch 13, Sec 2, 2.4.3 and IACS UR. Please confirm.

allowable
stressesvalue of leg
length2007/7/16

what is the design criteria (allowable stress value) when a leg length should
be calculated according loads? which corrosion deduction gas to be used forsuch calculations?

2007/5/1

As you mentioned, no adjustments to the weld length due to corrosion should
be made to plates with tc=4mm.
According to the proposed Background document for CSR Bulk, no
Until the rule change proposal is adopted by IACS, the interpretation of theadjustments to the weld length due to corrosion should be made to plates with note 2 in Table 1 is as follows.
tC = 4mm. This is not in line with note 2 in Table 1, which specifies that for+1.0mm for tc>5
tC=4 the leg length is to be increased by 0.5mm. Please explain.
+0.5mm for 5=>tc>4
0 for 4=>tc>3-0.5mm for 3=>tc

fillet weldside frames

Adjustments
to the weld
length due tocorrosion

The sizes of leg are determined based on the as-built thicknesses as per
Table.1 but the net thicknesses are not the basis. In case the requirements in
Chapter 11 should not be applicable the leg sizes should be subject to theSocieties approval

Page 1 of 6

IACS Common Structural Rules Knowledge Centre

KCID
No.

Ref.

507 11/2.2.6.1

Type

Question

Topic

The leglength of thefillet weld

Datecompleted2007/9/28

Question/CI

The leg length of the fillet weld is regulated in Ch11 Sec2, 2.6.1 and thissection stipulates to refer to Table 1.
Bulker CSR has no indication whether rounding treatment is to be applied ornot, even though Tanker CSR has rounding treatment in Sec6/5.7.1.1 of
Tanker CSR.
Please confirm which of the following leg length is to be applied:a. leg length as specified in Table 1;b. rounded leg length as specified in Table 1, nearest half millimetre.

Attachment

AnswerWe noted your comments.The draft interpritation will be submitted to Hulll
Panel for their view.
Also Included in Corrigenda 5

For example, if the leg length according to Table 1 is 7.2mm, then therequired leg length would be:- 7.2 mm for a;- 7.0mm for b.

508 11/2.2.6.2

651

669
attc

Table
11.2.2Table
11.2.1

RCP

Continuous
fillet welds

2007/10/9

The CSR of Ch.11,sec.2,2.6.2 is unreasonable considering other category.
Therefore the 2.6.2 might be reconsidered as below:"Where double continuous fillet welds in lieu of intermittent welds are applied,leg length of fillet weld is to be of Category F3."

2008/5/28

Reference is made to Ch. 11 Sec. 2 Table 2.
Please find enclosed an extract of all girder/primary supporting entries ofTable 2.
"Primary supporting member" in "Hull area" of Table 2 means the primary
1.General requirements to welding of primary supporting members is given in supporting member arranged in the structure other than double bottom and"Primary supporting members" => “Web plate and girder plate” to “Shell
double side structure, i.e., the primary supporting member with one plate
plating, deck plating, inner bottom plating(..) => F1 for "at end (15% of span)flange.
and F2 for "Elsewhere"
Therefore,the primary supporting members with two plate flanges such as
2.If we refer to “Bottom and double bottom” => “Side girder (..)” to “Bottom and girders or floors in double bottom, horizontal girder or transverses laying frominner bottom plating” => F3. This is in contradiction to item 1 above where the side to side in double side are not applicable to "Primary supporting
same structural elements are specified. There is no special consideration atmembers".
15% of span at ends. (Towards bulkheads)
3.If we refer to “Side and inner side in double side structure” => “Web ofIn order to clarify this matter, the words "and girder plate" in "Of" column forprimary supporting members” to “Side plating, inner side plating and web of
the Hull Area "Primary supporting members" should be deleted.
primary supporting members” => F2. Which is in line with item 1, except thatno increase is specified towards span ends.
We will issue the editorial corrections as a "Corrigenda" for clarification of thisQ1: Please comment on above understanding.
table.
Q2: We assume that girder web to shell plating to inner bottom/side should be
minimum F2 as given in “Primary supporting members”. Please advise.

CI

Girder/Primar
y supporting
members

RCP

Reference is made to Chapter 11 Section 2 Table 1. Thickness of abutting
plate. Ref note (1) “t is as-built thickness of the thinner of two connected
Thickness ofmembers” However, in Chapter 11 Section 2 Figure 1, t refers to “as-built
2008/10/10
abutting plate
thickness of abutting plate”. Assuming that t1>t2 in attached figure. From astrength continuity point of view we assume t1 should be applied whenevaluating the criteria. Please confirm Please update Table 1 accordingly.

We noted your comment. We will consider the edditorial correction.
Also Included in Corrigenda 5Your interpretation is right. We will consider the Rule Change proposal.

Y

Page 2 of 6

IACS Common Structural Rules Knowledge Centre

KCID
No.

Ref.

Type

672
Table 11.2 Question
attc

676

Table
11.1.1

757 11/1.1.2.1

781

Table
11.2.2

RCP

RCP

QuestionTopicfillet weld

IACS
recommenda
tion No.47

Bending
RadiusContinuous
fillet welds

Datecompleted

Answer

Attachment

2009/3/3

Ch11 Sec2, Table2 regulates the fillet welding as follows;- The ends of stiffeners : F0.
- The brackets at the ends of stiffeners : F1
In case of stiffeners which are fitted with brackets at the ends, we think it
acceptable to apply F1 welding to the ends of the stiffeners. (Please refer tothe attachment.) Please confirm the above.

Where a bracket is provided at the end of a PSM or an ordinary stiffener,stresses in a PSM or an ordinary stiffener may be reduced at its end.
Therefore, the fillet weld size F0 may be reduced to F1 which is the same asintended for brackets.
Table 2 will be updated accordingly.

Y

2008/5/6

As stated in Ch11 Sec1, 1.3.1, Table1 is based on IACS recommendation
No.47.
However, it does not match the latest one, Revision 3 of IACS
recommendation No.47 issued in November 2006.
We request to update Ch11 Sec1, Table1 as the latest one.

We will consider the rule change proposal.

2008/9/10

The minimum bending radius for cold forming is required to be at least 3 times
the plate thickness in Ch11 Sec1, 1.2.1 of CSR for Bulkers. With reference tothe relevant Technical Background (TB), this requirement originated from thestandard radius when bending corrugated bulkhead in IACS Rec. No. 47. On
the other hand, CSR for Tankers regulates the minimum bending radius for
We will condier the rule change proposal in order to be in line with IACS Rec.
cold forming is required to be at least twice the plate thickness in Sec6,
No. 47.
4.2.3.1. We are of the opinion that the minimum bending radius, 3 times theplate thickness, should be kept only when bending corrugated bulkhead. It isrequested that the minimum bending radius for cold forming in Ch11 Sec1,
1.2.1 of CSR for Bulkers be changed to twice the plate thickness.

2009/3/3

One side continuous fillet welding could be applied to stiffeners in a deckhouse subject to the following;
1. This welding method is not allowed for the area where is affected by theconcentrated loads and excessive vibration such as under winches, cranes,
davits and machineries and exposed to weather, and for wet spaces andtanks.
2. Welding size is to be of the fillet required by Ch.11, Sec.2, Table 1 forintermittent weld.
3. Welding at ends of the stiffeners is to be F0 according to the row "General,
unless otherwise specified in the table" in Ch.11, Sec.2, Table 2.
4. The fabrication process has to assure that the deviation from the given
angle of the profile to the plate is within the permissible values of thefabrication standard e.g. IACS REC47.

Question/CI

KC ID# 596 allows one side continuous fillet welding for stiffeners in deckhouse of CSR/Tanker except areas otherwise specified or those where suchwelding is not suitable. Is one side continuous fillet welding also allowed toapply to deck house of CSR/Bulker?

Page 3 of 6

IACS Common Structural Rules Knowledge Centre

KCID
No.

Ref.

Type

Topic

Date
completed

Question/CI

Attachment

Answer(1) and (2) Table 2 in Ch 11, Sec 2 is not applied to welding of hatch coverdirectly but the basic concept of Table 2 is applicable.

803

Table
11.2.2

Question

Welding
Sizes of
Hatch Cover2009/3/3

1] Please advise whether Table 2 in Ch.11, Sec.2 should be applied to
welding of hatch cover.
2] In case Table 2 in Ch.11, Sec.2 is not applicable to hatch cover pleaseconfirm that welding sizes should be subject to the Rules of the class.
3] In case Table 2 in Ch.11, Sec.2 should be applied to hatch cover,a) Please advise the rows and categories of welding in the table which to be
applied to the following connections:(1) Stiffener web to top plate/bottom plate(2) End of stiffener web to web of primary supporting member (PSM)(3) End of stiffener face to PSM web(4) PSM web to top plate/bottom plate(5) PSM web to PSM web at outermost end connections(6) PSM web to PSM web at intermediate connections(7) Web to face plate of PSM(8) PSM web to web of horizontal/vertical stiffener which is fitted on the PSMb) Please advise for which extent of categories (F0, F1, F2 or F3) theintermittent welding category “F4” can be used alternatively.
4] Please advise if the footnote (2) in Table 1 in Ch.11, Sec.2 is to be applied
to welding of hatch cover as it is.

(3) When the basic concept of Table 2 applies to welding of hatch cover, thecategory of the fillet weld of the following connection are as follows.
[3]a) (1) Stiffener web to top plate/bottom plate: F3 or F4*(2) End of stiffener web to web of primary supporting member (PSM):i) For bracket connection: F2ii) For no bracket connection: F1(3) End of stiffener face to PSM web:i) For bracket connection: F2ii) For no bracket connection: F1(4) PSM web to top plate/bottom plate: F2 at end (15% of span) and F3 or F4*
for the rest
(5) PSM web to PSM web at outermost end connections:i) For bracket connection: F2ii) For no bracket connection: F1(6) PSM web to PSM web at intermediate connections: F2(7) Web to face plate of PSM: F2 at ends (15% of span) and Fe3 or F4* for therest(8) PSM web to web of horizontal/vertical stiffener which is fitted on the PSM:
F4
Please note that F4 weld is not used for welding in way of intersection withPSM.
b) F3 weld instead of F4 can be used.

5] Please advise whether or not the intermittent welds, which have different[4] The footnote 2 of Table 1 is applicable
Length-Pitch other than “75-300” indicated in Table1 in Ch.11, Sec.2, can be
accepted. If accepted, please advise how to calculate the required Leg length.
[5] If the length of filet welds is greater than 75mm and pitch is less than
300mm, such intermittent welds are acceptable.
In order to this interpretation, we will consider a RCP.

Text
848
11/2.2.4.1

Table
11/2.1 &855
Text
11/2.2.6.1

Question

Question

abutting
platesfillet welds

2009/6/3

Ch.11 Sec.2 [2.4.1] Abutting plate panels forming boundaries to sea below
summer load waterline
In CSR Tanker partial penetration welding is acceptable for welding ofabutting plates forming boundaries to sea below summer load waterline whenthickness is greater than 12 mm.
In our opinion this should also be acceptable for CSR Bulk. Please advise.

2009/6/25

Leg length of fillet welds is adjusted corresponding to the corrosion addition as Considering the fillet weld category of side frame of single side structure
required in Ch11 Sec2, Table 1, Note (2). On the other hand, weld throats in(connection of side frame and end bracket to side shell plate) in Tab 2 Ch11
zones “a” and “b” of side frames are required in 2.6.1 without reference toSec2 is not referred to one specified in Tab1 Ch11 Sec2, the note (2) of Tab1
Table 1. Because this requirement originates from UR S12, adjustments ofis not applicable to fillet weld of side frame of single side structure (connection
those of side frames are considered unnecessary. Please confirm the above. of side frame and end bracket to side shell plate)

We agree that partial penetration welding is acceptable for welding of abutting
plates forming boundaries to sea below summer load waterline whenthickness is greater than 12 mm as per CSR OT. We will consider a Rule
Change Proposal

Page 4 of 6

IACS Common Structural Rules Knowledge Centre

KCID
No.

Ref.

938 11/2.2.2.2

Type

RCP

Topic

Welding ofplates ofdifferent
thicknesses

Datecompleted2010/3/30

Question/CI

Attachment

Answer

Ch.11, Sec.2 /2.2.2 of CSR-B specifies as following;“In the case of welding of plates with a difference in as-built thickness equal toor greater than 4mm, the thicker plate is normally tapered.”
However, the requirement in Sec.6/5.2.2.2 of CSR-T does not require plates
The tapering requirement will be harmonized to be in line with CSR OT. We
with a difference in thickness equal to 4mm. Moreover, based on experience,
will consider a rule change according to your comment.
we consider that this requirement of CSR-B need not include 4mm.
Please revise this requirement of CSR-B so that the wording "equal to or" isremoved and that it reads "as-built thickness greater than 4mm."943

11/2.1.4.1&2

RCP

Documentati
on to besubmitted
relating towelding and
NDE

Ch.11 Sec.2 [1.4.1] is rewritten as follows:
QUOTE
the welding plan to be submitted for approval has to contain the necessary
data relevant to the fabrication by welding of the structures.
UNQUOTE
2010/5/12

Ch.11 Sec.2 [1.4.1] and [1.4.2] need to be rewritten in order to follow UR Z23
5.1.5.

Ch.11 Sec.2 [1.4.2] is rewritten as follows:
QUOTE
the NDE plan to be submitted for aproval has to contain the necessary data
relevant to the locations and number of examinations, and the method of NDE
applied.
UNQUOTE
This will be done within a corrigenda.

Page 5 of 6

IACS Common Structural Rules Knowledge Centre

KCID
No.

966
attc

Ref.

Table
11.3.1

Type

RCP

Topic

Structural
testing ofballast holds

Datecompleted2009/9/11

Question/CI

Answer

Attachment

Structural Testing Requirements of CSR Rules for Bulk Carriers as applied toBallast Holds
LR Ship Rules; Part 3; Chapter 1; Section 8; Table 1.8.1 requires structural
testing of the water ballast holds in bulk carriers with the head, not less than,up to the top of the hatch coaming.
CSR Rules for BC; Ch. 11; Section 3.1; Table 1 requires structural testing toTable 11.3.1, which comes from UR S14, is kept as it is until UR S14 is
the greater of the head of water up to the top of overflow or 0.90 m head ofamended.
water above top of hatch. Excluding bulk carriers under 90 m in length, all new
bulk carriers will now be designed against these CSR Rules. Weather tighthatch cover seals for floodable cargo holds, are not suitable to retain a headof water, without leakage, so the application of the CSR Rule requirement cancause confusion for owners and shipyards.

Y

We believe this testing should be carried out to the top of the hatch coamingwith the hatch covers in place. Therefore we recommend that the text of the
CSR Rules for structural testing of the Ballast Hold in Bulk Carriers isamended in accordance with IACS Guidelines for Procedures of Testing
Tanks and Tight Boundaries:
CSR Rules for BC, Chapter 11, Section 3.1, Table 1 should be amended to :“The greater of - top of the overflow, or - top of cargo hatch coaming”
Note 2 to this table should also be amended in the final sentence to “in holds
for liquid cargo or ballast with large hatch covers, the highest point of tanks is
to be taken at the top of the hatch coaming."

1022 11/3.2.3.1

CI

Minimumpressure forhose testingin rules & UR
S14 2.3

2010/3/8

Ch.11 Sec.3 [2.3.1] hose testing.
The Rule requires a minimum pressure of 0.2X10^5 Pa. However, in IACS UR
S14 2.3, the minmum pressure for host testing is 2X10^5 Pa. Please clarify
whether there is a typo in CSR Bulk Rules or not. If not, please provide
relevant background for CSR.

There is a typo in CSR BC.
Ch.11 Sec.3 [2.3.1] will be corrected as follows:
The minimum pressure in the hose, at least equal to 2•10^5 Pa, is to be
applied at a maximum distance of 1,5 m

Page 6 of 6

KC#669
Reference is made to Chapter 11 Section 2 Table 1.
Figure

t1

t1

t2

t2

KC#672
Ch11 Sec2 Fillet welding

With reference to Table 2, the required fillet welding are as follows;

(

(

(

We think it acceptable to apply fillet welding as follows;(

Please confirm the above.

((

KC#966

IACS Guideline for Procedures of Testing Tanks and Tight Boundaries

1.

General

These test procedures are to ensure the weathertightness of structures/shipboard outfitting,
the watertightness of tanks and watertight boundaries and structural adequacy of tanks.
Tightness of all tanks and tight boundaries of the ships at the new construction and, whenmajor conversions or repairs* have been made, those relevant to the major
conversions/repairs should be confirmed by these test procedures prior to delivery of theship.
*

Major repair means a repair affecting structural integrity.

2.

Application

2.1
All gravity tanks** and other boundaries required to be watertight or weathertightshould be tested in accordance with this Guideline and proven tight and structurally
adequate as follows:-

Gravity Tanks for their tightness and structural adequacy
Watertight Boundaries Other Than Tank Boundaries for their watertightness, andWeathertight Boundaries for their weathertightness** Gravity tank means a tank having a design working pressure not greater than 70 kPa at
the top of the tank.
2.2
The testing of cargo containment systems of liquefied gas carriers should be inaccordance with standards deemed appropriate by the Administration.
2.3

Testing of structures not listed in Table 1 or 2 should be specially considered.

3.

Types of Tests and Definition of Test

3.1

The following two types of test are specified in this requirement:

Structural Test: A test to verify the structural adequacy of the construction of the tanks.
This may be a hydrostatic test or, where the situation warrants, ahydropneumatic test.
Leak Test:

A test to verify the tightness of the boundary. Unless a specific test isindicated, this may be a hydrostatic/hydropneumatic test or air test. Leak

test with remark *3 in Table 1 includes hose test as an acceptable mediumof the test.
3.2

Definition of each type of test is as follows:

Hydrostatic Test:(Leak and Structural)

A test by filling the space with a liquid to specified
head.

Hydropneumatic Test:(Leak and Structural)

A test wherein space is partially filled with liquid andair pressure applied on top of the liquid surface.

Hose Test:(Leak)A test to verify the tightness of the joint by a jet ofwater.

Air Tests:(Leak)A test to verify the tightness by means of air pressure
differential and leak detection solution. It includes tank
air test and joint air test, such as compressed air test
and vacuum box test.

Compressed Air Fillet Weld Test:(Leak)

An air test of fillet welded tee joint and leak indicating
solution applied on the fillet welds.

Vacuum Box Test:(Leak)

A box over a joint with leak indicating solution appliedon the fillet or butt welds. Vacuum is created inside thebox to detect any leaks.

Ultrasonic Test:(Leak)A test to verify the tightness of a sealing by means ofultrasonic.

Penetration Test:(Leak)A test to verify that no continuous leakages exist in theboundaries of a compartment by means of low surface
tension liquids.

4.

Test Procedures

4.1

GeneralTests should be carried out in the presence of the Surveyor at a stage sufficiently close to
the completion of the work with all hatches, doors, windows, etc. installed and all
penetrations including pipe connections fitted, and before any ceiling and cement work is
applied over the joints. Specific test requirements are given in 4.4 and Table 1. For thetiming of application of coating and provision of safe access to joints, see 4.5, 4.6 and Table
3.

4.2

Structural Test Procedures

4.2.1

Type and Time of Test

Where a structural test is specified in Table 1 or Table 2, a hydrostatic test in accordancewith 4.4.1 will be acceptable. Where practical limitations (strength of building berth, lightdensity of liquid, etc.) prevent the performance of a hydrostatic test, a hydropneumatic testin accordance with 4.4.2 may be accepted as an equivalent method.
Provided the results of a leak test are confirmed satisfactory, a hydrostatic test for
confirmation of structural adequacy may be carried out while the vessel is afloat.
4.2.2

Number of Structural Test

(1) Structural test should be carried out for at least one tank of same construction (i.e.,same design and same workmanship) on each vessel provided all subsequent tanks
are tested for leaks by an air test.
However, where structural adequacy of a tank was verified by structural testing
required in Table 1, the subsequent vessels in the series (i.e., sister ships built in thesame shipyard) may be exempted from such testing for other tanks which have thestructural similarity to the tested tank, provided that the water-tightness in all
boundaries of exempted tanks are verified by leak tests and thorough inspection
should be carried out. For sister ships built several years after the last ship of theseries, such exemption may be reconsidered. In any case, structural testing should
be carried out for at least one tank for each vessel in order to assure structural
fabrication adequacy.
(2) For watertight boundaries of spaces other than tanks (excluding chain lockers),
structural testing may be exempted, provided that the water-tightness in all
boundaries of exempted spaces are verified by leak tests and thorough inspection
should be carried out.
(3) These subsequent tanks may require structural test if found necessary after the
structural testing of the first tank.
(4) Tanks for structural test should be selected so that all representative structuralmembers are tested for the expected tension and compression.
4.3

Leak Test Procedures

For leak test specified in Table 1, tank air test, compressed air fillet weld test, vacuum box
test in accordance with 4.4.3 through 4.4.6, or their combination will be acceptable.
Hydrostatic or hydropneumatic test may also be accepted as leak test provided 4.5 and 4.6

are complied with. Hose test will also be acceptable for the locations as specified in Table 1
with the foot note *3.
Joint air test may be carried out in the block stage provided all work of the block that may
affect the tightness of the joint is completed before the test. See also 4.5.1 for theapplication of final coating and 4.6 for safe access to joint and their summary in Table 3.
4.4

Details of Tests

4.4.1

Hydrostatic Test

Unless other liquid is approved, hydrostatic test is to consist of filling the space by fresh
water or sea water, whichever is appropriate for testing of the space, to the level specified
in Table 1 or Table 2.
In case a tank for cargoes with higher density is to be tested with fresh water or sea water,
the testing pressure height should be specially considered.
4.4.2

Hydropneumatic Test

Hydropneumatic test where approved should be such that the test condition in conjunction
with the approved liquid level and air pressure will simulate the actual loading as far aspracticable. The requirements and recommendations for tank air tests in 4.4.4 will also
apply to hydropneumatic test.
4.4.3

Hose Test

Hose test should be carried out with the pressure in the hose nozzle maintained at least at
2·105 Pa during the test. The nozzle should have a minimum inside diameter of 12 mm andbe at a distance to the joint not exceeding 1.5meters.
Where hose test is not practical because of possible damage to machinery, electricalequipment insulation or outfitting items, it may be replaced by a careful visual examinationof welded connections, supported where necessary by means such as a dye penetrant test or
ultrasonic leak test or an equivalent.
4.4.4

Tank Air Test

All boundary welds, erection joints and penetrations including pipe connections should be
examined in accordance with the approved procedure and under a pressure differential
above atmosphere pressure not less than 0.15·105 Pa with a leak indication solution applied.
It is recommended that the air pressure in the tank be raised to and maintained at about
0.20·105 Pa for approximately one hour, with a minimum number of personnel around thetank, before lowered to the test pressure of 0.15·105 Pa.
A U-tube with a height sufficient to hold a head of water corresponding to the required test
pressure should be arranged. The cross sectional area of the U-tube should be not less thanthat of the pipe supplying air to the tank. In addition to U-tube, a master gauge or otherapproved means to verify the pressure should be approved.
4.4.5

Compressed Air Fillet Weld Test

In this air test, compressed air is injected from one end of fillet welded joint and thepressure verified at the other end of joint by a pressure gauge on the opposite side. Pressuregauges should be arranged so that an air pressure of at least 0.15·105 Pa can be verified ateach end of all passages within the portion being tested.
Note: Where the leak test is required in way of the fabrication applying the partial
penetration weld, compressed air test is also applied in the same manner for fillet
weld where the root face is sufficiently large, i.e., 6 – 8 mm.
4.4.6

Vacuum Box Test

A box (vacuum tester) with air connections, gauges and inspection window is placed over
the joint with leak indicator applied. The air within the box is removed by an ejector tocreate a vacuum of 0.20·105 – 0.26·105 Pa inside the box.
4.4.7

Ultrasonic Test

An arrangement of an ultrasonic echoes sender inside of a compartment and a receiver
outside. A location where the sound is detectable by the receiver displays a leakage in thesealing of the compartment.
4.4.8

Penetration Test

A test of butt welds by using of a low surface tension liquid at one side of a compartmentboundary. If no liquid were detected on the opposite sides of the boundaries after expirationof a definite time this means the verification of tightness of the compartments boundaries.
4.4.9

Other Test

Other methods of testing may be considered by each society upon submission of fullparticulars prior to commencement of the testing.
4.5

Application of Coating

4.5.1

Final Coating

For butt joints by automatic process, final coating may be applied anytime before
completion of leak test of the space bounded by the joint.
For all other joints, final coating should be applied after the completion of leak test of thejoint. See also Table 3.
The Surveyor reserves a right to require leak test prior to the application of final coatingover automatic erection butt welds.
4.5.2

Temporary Coating

Any temporary coating which may conceal defects or leaks should be applied at a time as
specified for final coating. This requirement does not apply to shop primer.
4.6

Safe Access to Joints

For leak tests, a safe access to all joints under examination should be provided. See also
Table 3.

Table 1
Test Requirements for Tanks and Boundaries
Tank or boundary
to be tested

Test type1

Double bottom tanks*4

Leak &
Structural*1

2

Double bottom voids*5

Leak

3

Double side tanks

Leak &
Structural*1

4

Double side voids

Leak

5

Deep tanks other than thoselisted elsewhere in this table

Leak &
Structural*1

6

Cargo oil tanks

Leak &
Structural*1

7

Ballast hold of bulk carriers

Leak &
Structural*1

8

Peak tanks

Leak &
Structural*1

a. Fore peak voids

Leakb. Aft peak voids

Leak

Cofferdams

Leaka. Watertight bulkheads

Leakb. Superstructure end
bulkhead

Leak

9

10
11

Test head or pressure
The greater of- top of the overflow,- to 2.4m above top oftank *2, or- to bulkhead deckSee 4.4.4 through 4.4.6, asapplicableThe greater of- top of the overflow,- to 2.4m above top oftank *2, or- to bulkhead deckSee 4.4.4 through 4.4.6, asapplicableThe greater of- top of the overflow, or- to 2.4m above top oftank *2
The greater of- top of the overflow,- to 2.4m above top oftank *2, or- to top of tank *2 plus
setting of any pressure
relief valve
The greater of- top of the overflow, or- top of cargo hatchcoaming
The greater of- top of the overflow, or- to 2.4m above top oftank *2
See 4.4.4 through 4.4.6, asapplicable
See 4.4.4 through 4.4.6, asapplicable
See 4.4.4 through 4.6, asapplicable
See 4.4.3 through 4.4.6, asapplicable
See 4.4.3 through 4.4.6, asapplicable

Remarks

After peak to be tested
after installation ofstern tube

After peak to be tested
after installation ofstern tube

12

Watertight doors below
freeboard or bulkhead deck

Leak *6

13

Double plate rudder blade

Leak

14

Shaft tunnel clear of deep
tanks

Leak *3

15

Shell doors

Leak *3

16

Weathertight hatch covers
and closing appliances

Leak *3

See 4.4.3 through 4.4.6, asapplicable

17

Dual purpose tank/dry
cargo hatch cover

Leak *3

See 4.4.3 through 4.4.6, asapplicable

18

Chain locker

Leak &
Structural

Top of chain pipe

19

Independent tanks

Leak &
Structural*1

20

Ballast ducts

Leak &
Structural*1

Note:

*1

*2
*3
*4
*5
*6

See 4.4.3 through 4.4.6, asapplicable
See 4.4.4 through 4.4.6, asapplicable
See 4.4.3 through 4.4.6, asapplicable
See 4.4.3 through 4.4.6, asapplicable
Hatch covers closed bytarpaulins and battens
excluded
In addition to structural
test in item 6 or 7

The greater of- top of the overflow, or- to 0.9m above top oftank
The greater of- ballast pump maximum
pressure, or- setting of any pressure
relief valve

Structural test is to be carried out for at least one tank of same construction (i.e., same design and same
workmanship) on each vessel provided all subsequent tanks are tested for leaks by an air test. However,where structural adequacy of a tank was verified by structural testing, the subsequent vessels in the series(i.e., sister ships built in the same shipyard) may be exempted from such testing for other tanks which havethe structural similarity to the tested tank, provided that the water-tightness in all boundaries of exemptedtanks are verified by leak tests and thorough inspection are to be carried out. In any case, structural testing
is to be carried out for at least one tank for each vessel in order to assure structural fabrication adequacy.
(See 4.2.2(1))
Top of tank is deck forming the top of the tank excluding any hatchways.
Hose Test may also be considered as a medium of the test. See 3.2.
Including tanks arranged in accordance with the provisions of SOLAS regulation II-1/9.4
Including duct keels and dry compartments arranged in accordance with the provisions of SOLAS
regulation II-1/9.4
Where water tightness of watertight door has not confirmed by prototype test, testing by filling watertightspaces with water is to be carried out. See SOLAS regulation II-1/16.2 and MSC/Circ.1176.

Table 2
Additional Test Requirements for Special Service Ships/Tanks
Type ofShip/Tank

Structures to betested1

Liquefied gas
carrier

Cargo containment
systems (Seeremarks)

See 4.4.1

2

Edible liquid
tanks

Independent tanks

Leak &
Structural

3

Chemicalcarrier

Integral or
independent cargotanks

Leak &
Structural

Note:

*1

Type of
Test

Test Head or Pressure

Remarks

See 4.4.1

See also Table
1 for othertanks andboundaries

The greater of- top of the overflow, or- to 0.9m above top oftank *1
The greater of- to 2.4m above top oftank *1, or- to top of tank *1 plus
setting of any pressure
relief valve

Top of tank is deck forming the top of the tank excluding any hatchways.

Table 3
Application of Leak Test, Coating and Provision of Safe Access
For
Type of Welded Joints

Type of Welded Joints

Leak Test

Coating *1
After
Leak Test &BeforebeforeLeak Test
Structural
Test

Automatic

Not required

Allowed

N/A

Not
required

Required

Not allowed

AllowedRequired

Required

Not allowed

AllowedRequired

Butt

Manual or
Semi-automatic
Boundary
includingpenetrations

Fillet
Note:

*1
*2

Safe Access *2

Leak Test

Structural
Test
Not
requiredNot
requiredNot
required

Coating refers to internal (tank/hold coating), where applied, and external (shell/deck) painting. It does notrefer to shop primer.
Temporary means of access for verification of the leak test