IACS Common Structural Rules Knowledge Center

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

Ref.

Type

188

1/1.1.1.1 &Question
1/1.3.1.1

189

1/1.1.1.2

190
attc

191

1/1.1.1.2

1/1.1.1.2

Question

Question

Question

Topic

Date
completedlength

2006/10/2

Which length is correct? 150m or 90m?

Both are correct. The CSR for bulk carriers apply to ships of 90m or above in
general. Sub-sec.[3.1.1] corresponds to UR S25 which applies to ships of
150m or above. These definitions are kept as they are.

application of
CSR

2006/10/2

Does CSR apply to the bulk carrier with box shape which does not have bilge
hopper tank and top side tank?

No, the CSR for bulk carriers do not apply to a bulk carrier which does nothave hopper side tank and topside tank in cargo holds length area.

2006/10/2

With bulk carriers is intended sea going self-propelled ship which areconstructed generally with single deck, double bottom, hopper side tanks andtopside tanks and with single or double side skin construction in cargo length
No, the CSR for bulk carriers do not apply to such bulk carriers which arearea and intended primarily to carry dry cargoes in bulk. Hybrid bulk carriers,
constructed with topside tank but without hopper side tank in cargo holds
where at least one cargo hold is constructed with hopper tank and topside
length area.
tank, are covered by the present Rules. The structural strength of members inholds constructed without hopper tank and/or topside tank is to comply withthe strength criteria defined in the Rules. (See attachment)

2006/10/2

Are the following ships not subject to CSR due to their cross section design?
- ore carrier- combination carrier- cement carrier- wood chip carrier- open hatch carrierNo, such ships are not subject to the CSR for bulk carriers.

(1) Yes, the ships with cross sections indicated in figure are defined as bulk
carriers.
(2) The treatment of "Novel features" and "unusual hull shapes" depends onthe discretion of each Classification Society.

The midship part is the extent of 0.3L to 0.7L from the aft end (A.E.) of the rule
length L.

application ofCSR

application of
CSR

Question/CI

192
attc

1/1.1.1.5

Question hull materials

2006/10/2

Ships whose hull materials are different than those given in [1.1.4] and ships
with novel features or unusual hull design are to be individually considered by
the society, on the basis of the principles and criteria adopted in the present
Rules.
(1) Is the word “ships” the bulk carriers as defined in [1.1.2]? (see drawing 1 in
attachment)(2) Can “Novel features” and “unusual hull shapes” be used to include vessels
as shown? See drawing 2 in attachment - Can this design the included in theterm novel feature?

193

1/4.3.3.3

Question

length

2006/10/2

The midship part of a ship is the part extending 0.4L amidship, unlessotherwise specified.” Could you elaborate on what this means?

279
attc

1/1.1.1

Question

application

Attachment

AnswerIs CSR applicable for VLOO (Very Large Oil or Ore) carrier having
2006/11/13 configuration very similar to VLCC, but with hatch opening in center hold/tank? CSR Tanker or Bulker Rules are not applicable for Ore-Oil Carriers.
See attached sketch.

Y

Y

Y

Page 1 of 6

IACS Common Structural Rules Knowledge Center

KCID
No.

Ref.

Type

Topic

Date
completed

Question/CI

Attachment

Answer

1.Your comments have been noted and we will clarify the application of theflooding requirement in a future revision of the rules.

361
attc

1/3.2.2.2

Question

Flooding
Scenario

2009/9/4

According to this functional requirement, we assume that flooding scenario
should be taken care of for all ships. It is unclear how this is taken care of for
BC-C vessels and for small ships with length below 150 m. It should be
explained and included in the rules or if applicable, the functional requirement
should be modified for sake of clarity.
Meantime, please confirm if our understanding of the current CSR is correct
as summarized in the table attached. In the following questions we also
highlight our concerns.

2.Regarding the summarized table as attached, the answer is as follows.
(1)Design still water bending moment and shear forces, your understanding iscorrect.
(2)Design wave bending moments and sheer forces, your understanding iscorrect.
(3)Longitudinal strength (Yielding), your understanding is correct.
(4)Longitudinal strength (Buckling), your under standing is correct.
The answer to the question in the “Remark” box in the attached document is
as follow.
No, the axial buckling check according to UR S17 is not applied to. Hull girder
ultimate strength check should be carried out in stead of the axial bucklingcheck.
(5)Hull girder ultimate strength, your understanding is correct.
The answer to the question in the “Remark” box in the attached document is
as follow.
Yes, hull girder ultimate strength applies to BC-C ships.
(6)Design loads for corrugations of transverse bulkhead: your understanding iscorrect.

Y(7)Strength of corrugation of transverse watertight bulkhead: yourunderstanding is correct.
(8)Shear buckling strength of corrugation of transverse watertight bulkhead:
this is applied to all ships according to “Corrigenda 2 approved by IACS
Council on 27 January 2007.”.
(9)Flooding scenario for double bottom: your understanding is correct.
(10)Design load and strength of double bottom: your understanding is correct.
(11)Design load for boundaries of dry compartment: your understanding iscorrect.
The answer to the question in the “Remark” box in the attached document is
as follow.
Where sigma x is not defined for longitudinal members, sigma-x for intact
condition is used.
The MwH,f is not considered.
Combination factor for intact condition is used.
(12)Design load and strength of primary supporting members on theboundaries of dry compartment; your understanding is correct. There is norequirement in CSR.
(UPDATED OCT 2009)

410
attc

1/1.1.2

Question

Lime Stone
Ship

2007/3/15

Is CSR/Bulker applied to the attached self-unloading lime stone ship ?

No, the CSR is not applicable to the concerned design of the self-unloading
lime stone ship.

Page 2 of 6

YIACS Common Structural Rules Knowledge Center

KCID
No.

Ref.

Type

Topic

Date
completed

436
attc

1/1.1.1.2

Question

Selfunloadingbulk carrier

2007/4/6

473
attc

511
attc

514

1/1.1.1.2

1/1.1.1.2

1/4.2.1.1

CI

Question/CI

Is the self-unloading bulk carrier, showed in the attached file, NOT a CSR-bulk Your interpretation is right. This self-unloading bulk Carrier is not a CSR-bulk
carrier like the lime stone carrier of question #410?
carrier as defined in Ch 1, Sec 1, 1.1.2.

Ch.1 Section.1 1.1.2:
Structural
Please see attachment for structural arrangement of bulk carrier in midshiparrangement
hold and hold adjacent to engine room. Please note:of bulk- Vessel has no hopper tank in parallel midship area
carrier in
2007/10/24 - Vessel has a sloped hopper-like shape in bilge area due to hull shape.
midship hold
Hopper shape is extending the entire cargo hold.
and hold
Please advice if the vessel falls within the category "hybrid bulk carrier" asadjacent tostated in 1.1.2. and whether or not CSR is mandatory for this design.
engine room.
Common guidelines urgently needed

Question

Midship
section &Sections incargo holds

CI

Definition of
Ship's speed
V

Attachment

AnswerY

According to the clause in Ch.1, Sec.1 [1.1.2], the subject design needs tocomply with the CSR for Bulk Carrier.

Y

In case of designs as per the sketches No.3) thru 6) for No.1 cargo holdsection CSR needs not be applied. However CSR needs to be applied for thecase of sketches No.2.

Y

2007/9/25

The midship section and sections in cargo holds other than NO.1(Foremost)cargo holds are as per No.1) Midship in the attached sketches. There are 5
kinds of designs of NO.1 cargo hold as shown in No.2) through No.6) in theattached sketches. Please advise whether the respective designs No.2)
through No.6) need to comply with the CSR requirements.

2007/8/28

Ship’s speed, V, is defined in Ch1 Sec4, 2.1.1 as Maximum ahead service
speed, in knots. My understanding is that the definition of V in CSR is same as Yes, your understanding is correct.
the one in 2.1.1 of UR S10, namely maximum service speed (knots) with the
Also Included in Corrigenda 5
ship on summer load waterline. Is my understanding correct?

Page 3 of 6

IACS Common Structural Rules Knowledge Center

KCID
No.

548

Ref.

1/1.1.1.2

Type

Topic

Ship notQuestion being HybridBC

Datecompleted2007/10/9

Question/CI

Attachment

Answer

If a ship is not an hybrid-BC according to CSR definition in Chapter 1, 1.1.2(i.e. for the considered ship no one hold has hopper tank and topside tank), it
is not required to apply the CSR.
In case an owner intends to build a ship longer than 90 m having all cargoholds of box type and expected to carry cargo in bulk for a number of travels ayear, i.e. a bulk carrier according to SOLAS chapter XII, the following
questions are to be answered:
1.if the Shipyard or Ship-owner asks - for any commercial reason - to classify
the ship (which is not hybrid because all the holds are without hopper andlower tanks) as Bulk Carrier, can each Society decide to classify the ship as
Bulk Carrier without applying the CSR? Applicable Rules would be eachSociety’s Rules for BC and the URs to Bulk Carriers.
The questions are considered to be outside of PT1's scope of work.
It is requested to Hull Panel to provide answer to your questions.
2.if the Shipyard or Shipowner asks to classify the ship (which is not hybrid
because all the holds are without hopper and lower tanks) as Bulk Carrier withscantlings according to CSR, can each Society decide to classify the ship as
Bulk Carrier applying the CSR even if Chapter 1, 1.1.2 does not require it?
The CSR can be applied, because in 1.1.2 is stated that “The structural
strength of members in holds constructed without hopper tank and/or topsidetank is to comply with the strength criteria defined in the Rules.“, meaning
therefore that the CSR scantling can be applied to such holds.
It is to be noted that in no case ESP will apply as this is not required under
SOLAS XI-1 Reg.2.

586
attc

587
attc

1/1.1.1.2

1/1.1.1.2

In case we have an inclined longitudinal bulkhead, is it possible to consider
there is no hopper tank and therefore not to apply CSR Rules?
If this inclined longitudinal bulkhead is made with small change with two
slopes, is it possible to consider there is no hopper tank?

CI

Longitudinal
BulkheadA few similar questions have already raised to IACS KC. IACS works on an
entire answer for the application of the CSR-BC for different ship designs,
considering a clear definition of the hopper tank.

Y

CI

Structure ofPlease see attachment for structure of bulk carrier in midship hold and aft andbulk carrier in
A few similar questions have already raised to IACS KC. IACS works on anfore body hold.
midship, aft 2007/10/24
entire answer for the application of the CSR-BC for different ship designs,
In this case, whether or not is CSR mandatory?
and foreconsidering a clear definition of the hopper tank.
body holdY

2008/4/24

Page 4 of 6

IACS Common Structural Rules Knowledge Center

KCID
No.

601

Ref.

1/1.1.1.2

Type

Question

Topic

Application toconvert ships

Datecompleted2008/3/14

Question/CI

Attachment

AnswerCSR Application to converted ship;
In response to the recent demands of the bulker market, there are many
conversion plan of the existing tanker into bulk carrier. The most of such plans
indicate that hull envelope (i.e., bottom, side and portions of deck structures)of the existing ship is retained as original and inner bottom structures and
TST/hopper tank shaped structures (void) are newly installed for satisfactorily
comply with the grain stability. Such conversion is considered as a "major
conversion" under the statutory requirements. However, it is not clear inapplication of CSR for bulk carrier. Please advise of your views for thefollowing inquiries:
Q1: In line with the definition of "alterations and modifications" of the statutory
requirements, such as SOLAS II-2Reg. 1.2.3.2.(FP), is CSR for bulk carriers
The issue is being discussed at Hull Panel for Council decision on the IACS
required to be applied to the converted bulk carrier? Please advise your views.
procedures to be followed.
Q2: There is no clear statement in the current text on applicability of CSR for
bulk carriers which undergo alterations and modifications or conversion fromother type of ship into bulk carrier. We would think such statement should beindicated in the text.
Q3: Is such applicability related to the extent of conversion ? If yes, we would
think that definition of "(Minor) Conversion" or "Major Conversion" should be
defined in the application of CSR for bulk carrier with the clear extent of
conversion, e.g., new cargo hold structures replace the existing cargo area
construction for XX% of the entire hull structures

604

680

1/4.2.1.1 &Question
4/3.2.4

LongitudinalStrength
Calculation

1/1.1.1.2

Bilge hoppertank and
VOID

Question

2008/5/6

It is mandatory to make Longitudinal Strength Calculation for one flooded holdfor Bulk Carriers having length of 150 m or above; according to SOLAS Ch.
XII Reg. 5. For that calculation the length of the ship is to be taken as Loadline
Length according to SOLAS Ch. XII Reg. 1
SOLAS Rule Reference: SOLAS Ch. XII Reg. 1 (for length definition) &SOLAS Ch. XII Reg. 5 (for Strength Calculation).
The rule length as defined in Ch 1, Sec 4, [3.1.1] should be used for the
According to CSR for Bulk Carriers the same calculation for flooded holddetermination of still water bending moment and still water shear force inshould be carried out but in CSR it is stated that the length of the ship is to be
flooded condition according to Ch 4, Sec 3, [2.4].
taken as the Rule Length.
CSR Rule Reference: CSR Ch.1 Sec. 4 2.1.1 (for length definition) & CSR
Ch.4 Sec. 3 2.4 (for Strength Calculation)
In our project, the Rule Length < 150 m while the Loadline Length > 150 m.
Would you please advise what kind of application should be followed? Should
the strength calculation be made in this particular case? Which length should
be taken into consideration?"

2008/6/19

This bulk carrier is arranged with bilge hopper tank and VOID or TRUNK
space at deck as attached.
Please confirm whether CSR should be applied to the bulk carrier or not.

As stated in Ch1 Sec1, 1.1.2, CSR should be applied to a bulk carrier withtopside tanks. The questioned bulk carrier also has the configuration of
topside tanks, where VOID or TRUNK space is arranged in your sketch. The
usage of the space does not affect the application of CSR.
Accordingly, the ship should be applied with CSR.

Page 5 of 6

IACS Common Structural Rules Knowledge Center

KCID
No.

692

982

Ref.

1/1.1.1.2

1/1.1.1.6

1027 1/1.3.2.1

Type

CI

CI

RCP

Topic

combination
carrierDefinition of"assigned
freeboard"

Additional
GRAB
notation forships using
grab

Date
completed

Question/CI

Attachment

Answer

2008/9/10

Reference is made to Ch.1 Sec. 1 [1.1.2] . Vessel in question is a 7 hold
Bulk carrier where 3 holds are arranged for carriage of Caustic Soda. Vessel
has traditional bulk carrier cross section with top wing and hopper tank in
As the ship is 7 hold Bulk carrier having cross section with top wing andcargo area . According to [1.1.2] CSR is not applicable for combination
hopper tank in cargo area, even if some holds are arranged for carriage ofcarriers. However, combination carrier according to SOLAS definition is a
Caustic Soda, it should be considered as a CSR bulk carrier, if intended
vessel that can carry both dry bulk and oil. As Caustic soda is characterized as primarily to carry dry cargoes in bulk, which seems to be the case. An
a chemical and not oil we are of the opinion that above vessel can not be
additional consideration to necessary equipment and hydrodynamic load due
considered a combination carrier. Following this, we consider that this vessel to loading of caustic soda solution, if applicable, should be made , whichshall comply with CSR in addition to be designed to carry Caustic soda in the should be subject to the review and approval of the class.
specified cargo holds. Design loads from the liquid cargo will be used andbased on the principles as given in CSR. Please advice.

2010/6/29

Ch 4 Sec.7, 1.2.3 specifies that “the maximum loading condition draught is tobe taken as the moulded summer load line draught.”
In the above context, Ch1 Sec1, 1.1.6 defines that “the scantling draught
considered when applying the present Rules is to be not less than that
corresponding to the assigned freeboard.” We understand that the term“assigned freeboard” means the moulded summer load line draught.
On the other hand, we understand that the draught of ships to which timber
freeboards are assigned corresponds to the loading condition of timber, andthat the requirements of the individual Classification Society may apply to thisdraught.
Please confirm that our understanding is correct.

2010/3/30

According to CSR BC Chap1/1.3.2.1 additional class notation GRAB[X],GRAB is mandatory for ships having notation “BC-A“ or “BC-B”. I understandthat this requirement is result from UI SC208 and SOLAS XII/6.5.1 and there
are no restrictions for GRAB in UI SC208 if any ships want to have notation
GRAB.
Chap1/1.3.2.1 for ships with notation BC-C causes confusion. For example,
the notation GRAB is not mandatory for ships with BC-C to carry coal of cargodensity less than 1.0 t/m3. All of us know that grab may be used to dischargecoal.

Your understanding is correct.
The term “assigned freeboard” means the moulded summer load line draught.
The draught of ships to which timber freeboards are assigned corresponds tothe loading condition of timber, and the requirements of the individual
Classification Society may apply to this draught.

As said in the CSR BC, Ch.1 Sec.1 [3.2.1], the assignation of the GRAB
notation to a BC-C ship is voluntary and is intended to scope heavy grabs(over 20t of unladen weight).
Making this notation mandatory for all ships loaded or unloaded by grabs may
induce increases in scantlings even for lighter grabs; this is not the intent ofthese rules.

Therefore, Please correct a few sentences of Chap1/1.3.2.1 as follows:
The text is kept as it is.
Mandatory for ships having one of the additional service features BC-A or BCB, according to [3.1.2].
=> Mandatory for ships using GRAB.

Page 6 of 6

KC#190

KC#192
attachment
Drawing 1:

Drawing 2:

KC#279

KC#361
Flooding requirements of CSR Bulker
Q1 Ch 1 Sec 3 [2.2.2]
According to this functional requirement, we assume that flooding scenario should be taken careof for all ships. It is unclear how this is taken care of for BC-C vessels and for small ships withlength below 150 m. It should be explained and included in the rules or if applicable, thefunctional requirement should be modified for sake of clarity. Meantime, please confirm if ourunderstanding of the current CSR is correct as summarized in the table below. In the following
questions we also highlight our concerns.
<Summary of flooding requirements (strength requirements are highlighted)>
Item

Rule ref.

Design still water bending
moments and shear forces
Design wave bending
moments and shear forces
Longitudinal strength(yielding)

Ch 4 Sec 3 [2.4]

X

X

X

Ch 4 Sec 3 [3.1.2]
and [3.2.2]
Ch 5 Sec 1 [2.1.3],[2.2.3], [4.2.2],[4.3.1] and [5.3]
Ch 6 Sec 3 [1.1.2]

X

X

X

X

--

--

--

--

--

Ch 5 Sec 2
Ch 4 Sec 6 [3.3]

X
X

X
X

-X

Ch 6 Sec 1 [3.2.3]
and Sec 2 [3.2.6]

X

X

X

Above URS18

Ch 6 Sec 3 [6]

X

--

--

As per URS18

Ch 4 Sec 6 [3.4]

X

X

X

Ch 6 Sec 4 [3]

X

--

--

As per URS20

Ch 4 Sec 6 [3.2.1]

X

X

X

The az for intact?

Ch 6 Sec 1 [3.2.2]
and Ch 6 Sec 2[3.2.5]

X

X

X

?

?

?

?

The sig-x not defined
for longitudinal
members? Applysame MSW,F forflooding of a dry holdand duct keel? Is
MWH,F considered?
How about
combination factors/
Example:Fore end bulkhead of
foremost hold or aft
end bulkhead of
aftermost hold.

Longitudinal strength(buckling)
Hull girder ultimate strength
Design load for corrugationsof transverse watertightbulkheads
Strength of corrugations oftransverse watertightbulkheads
Shear buckling strength ofcorrugations of transverse
watertight bulkheads
Flooding scenario for double
bottomDesign load and strength of
double bottom
Design load for boundaries ofdry compartments
Strength of local plates andstiffeners on the boundaries ofdry compartments

Design load and strength ofprimary supporting memberson the boundaries of drycompartments

Note: “X” : applicable,

BC-A and
BC-B

BC-C

“-- “ : not applicable, “?” : unclear.

L < 150m

RemarkAxial buckling checkaccording to URS17?
Apply to BC-C?

KC#410

1. Machinery Space

2. Belt Conveyor Space is penetrating throughall bulkheads in cargo holds and continuing
throught Cargo Area.

KC#436

KC#473
End hold configuration. Sloped ”hopper” due to shape in bilge:

Midship configuration:

Filename:
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Directory:
C:\Documents and Settings\IACSUser\My Documents
Template:
C:\Documents and Settings\IACSUser\Application
Data\Microsoft\Templates\Normal.dot
Title:End hold configuration
Subject:
Author:Hans Olav Strømme
Keywords:
Comments:
Creation Date:
22/10/2007 10:56 AM
Change Number:
3
Last Saved On:
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Last Saved By:
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Total Editing Time: 1 Minute
Last Printed On:
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As of Last Complete Printing
Number of Pages: 1
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22 (approx.)
Number of Characters: 128 (approx.)

KC#511

KC#586

KC#587