oSIST prEN ISO 11812:2023
(Main)Small craft - Watertight or quick-draining recesses and cockpits (ISO 11812:2020)
Small craft - Watertight or quick-draining recesses and cockpits (ISO 11812:2020)
This document specifies watertightness, draining time and sill heights requirements for watertight and quick-draining recesses and cockpits in small craft of up to 24 m load line length (see Reference [1]).
Recesses located in elevated parts of the craft are covered by this document.
This document does not specify requirements for the size, the shape and the location of recesses or cockpits. It only considers draining by gravity, and not by pumping or other methods.
It only considers normal operation of the craft, but unattended craft recess issues are out of scope.
This document does not guarantee that the water contained in a watertight or quick-draining recess or cockpit will not affect the stability and buoyancy of the craft, which are covered by ISO 12217 (all parts):2015.
Kleine Wasserfahrzeuge - Wasserdichte und schnell-lenzende Rezesse und Plichten (ISO 11812:2020)
Petits navires - Cavités et cockpits étanches ou rapidement autovideurs (ISO 11812:2020)
Le présent document spécifie les exigences relatives à l'étanchéité, au temps de vidange et à la hauteur des surbaux pour les cavités et les cockpits étanches et rapidement autovideurs dans les petits navires d'une longueur de ligne de charge inférieure ou égale à 24 m (voir la Référence [1]).
Les cavités situées dans les parties surélevées du bateau sont couvertes par ce document.
Ce document ne spécifie pas les exigences concernant la taille, la forme et l'emplacement des cavités ou des cockpits. Il ne prend en compte que la vidange par gravité, et non par pompage ou par d'autres méthodes.
Il ne prend en compte que le fonctionnement normal du bateau, mais les problèmes relatifs aux cavités des bateaux laissés sans surveillance sont en dehors du domaine d'application.
Ce document ne garantit pas que l'eau contenue dans une cavité étanche et rapidement autovideuse n'affectera pas la stabilité et la flottabilité du bateau, qui sont couvertes par l'ISO 12217 (toutes les parties):2015.
Mala plovila - Vodotesni prostori ter prostori in kabine s hitrim odvajanjem vode (ISO 11812:2020)
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
oSIST prEN ISO 11812:2023
01-september-2023
Nadomešča:
SIST EN ISO 11812:2018
Mala plovila - Vodotesni prostori ter prostori in kabine s hitrim odvajanjem vode
(ISO 11812:2020)
Small craft - Watertight or quick-draining recesses and cockpits (ISO 11812:2020)
Kleine Wasserfahrzeuge - Wasserdichte und schnell-lenzende Rezesse und Plichten
(ISO 11812:2020)
Petits navires - Cavités et cockpits étanches ou rapidement autovideurs (ISO
11812:2020)
Ta slovenski standard je istoveten z: prEN ISO 11812
ICS:
47.080 Čolni Small craft
oSIST prEN ISO 11812:2023 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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oSIST prEN ISO 11812:2023
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oSIST prEN ISO 11812:2023
INTERNATIONAL ISO
STANDARD 11812
Second edition
2020-07
Small craft — Watertight or quick-
draining recesses and cockpits
Petits navires — Cavités et cockpits étanches ou rapidement
autovideurs
Reference number
ISO 11812:2020(E)
©
ISO 2020
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
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Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 5
5 General . 6
5.1 Loading and measurement conditions . 6
5.2 Requirements for watertight and quick-draining recesses . 6
6 Watertightness requirements. 6
6.1 Watertightness requirements for watertight recesses . 6
6.2 Watertightness requirements for quick-draining recesses . 7
7 Requirements for companionway sills . 7
7.1 Companionway sills . 7
7.2 Quick-draining recess with a reduced risk of flooding . 8
7.3 Sill height measurement . 8
7.4 Minimum companionway sill height for quick-draining recesses . 8
8 Height of recess bottom above waterline for quick-draining recesses .8
9 Quick-draining recesses — Single bottom recess drainage . 9
9.1 Drainage general requirements . 9
9.2 Drain requirements . 9
9.2.1 Number and dimensions . 9
9.2.2 Special provisions . 9
9.2.3 Installation .10
9.3 Drainage calculation requirements .10
9.3.1 Drainage calculation principle and assessment methods .10
9.3.2 Simplified drainage assessment method .11
10 Quick-draining recesses — Multi-bottom recess drainage .12
10.1 Drainage general requirements .12
10.2 Drainage calculations .12
10.3 Drainage requirements for a foot basin .13
11 Owner’s manual.14
11.1 General recommendation for use .14
11.2 Recommendation for use from Table 4 — Companionway opening .14
Annex A (normative) Full calculation method for draining time .16
Annex B (informative) Technical background — Source of the calculations used .24
Annex C (informative) Examples of “quick-draining” recesses .30
Bibliography .32
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the WTO
principles in the Technical Barriers to Trade (TBT), see Foreword - Supplementary information.
This document was prepared by Technical Committee ISO/TC 188, Small craft.
This second edition cancels and replaces the first edition (ISO 11812:2001), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— systematic usage of the general term "recess" instead of "cockpit";
— introduction of the concept of recess open to the sea and recess with reduced risk of flooding;
— clarification of requirements;
— clarification of requirements on engine ventilation openings installed in recesses;
— implementation of multi-bottom recesses or recesses with a foot-basin in the main core of the
standard;
— deletion of "major head losses" (friction in drain pipes) as their effect was very small, but this made
the calculation much more complex;
— improved data for "minor head losses" (local losses) to correspond to common practice;
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
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oSIST prEN ISO 11812:2023
INTERNATIONAL STANDARD ISO 11812:2020(E)
Small craft — Watertight or quick-draining recesses and
cockpits
1 Scope
This document specifies watertightness, draining time and sill heights requirements for watertight and
quick-draining recesses and cockpits in small craft of up to 24 m load line length (see Reference [1]).
Recesses located in elevated parts of the craft are covered by this document.
This document does not specify requirements for the size, the shape and the location of recesses or
cockpits. It only considers draining by gravity, and not by pumping or other methods.
It only considers normal operation of the craft, but unattended craft recess issues are out of scope.
This document does not guarantee that the water contained in a watertight or quick-draining
recess or cockpit will not affect the stability and buoyancy of the craft, which are covered by
ISO 12217 (all parts):2015.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
1)
ISO 8666:2016 , Small craft — Principal data
1)
ISO 9093-1:1994 , Small craft — Seacocks and through-hull fittings — Part 1: Metallic
1)
ISO 9093-2:2002 , Small craft — Seacocks and through-hull fittings — Part 2: Non-metallic
ISO 12216:2020, Small craft — Windows, portlights, hatches, deadlights and doors — Strength and
watertightness requirements
ISO 12217-1:2015, Small craft — Stability and buoyancy assessment and categorization — Part 1: Non-
sailing boats of hull length greater than or equal to 6 m
ISO 12217-2:2015, Small craft — Stability and buoyancy assessment and categorization — Part 2: Sailing
boats of hull length greater than or equal to 6 m
ISO 12217-3:2015, Small craft — Stability and buoyancy assessment and categorization — Part 3: Boats of
hull length less than 6 m
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
1) Under revision.
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
3.1
design category
description of the sea and wind conditions for which a craft is assessed to be suitable
Note 1 to entry: The design categories are defined in ISO 12217 (all parts):2015.
Note 2 to entry: The definitions of design categories are in line with the European Recreational Craft Directive
2013/53/EU.
3.2
sailing craft
craft for which the primary means of propulsion is by wind power, having a reference sail area
2/3
A ≥ 0,07(m ) , expressed in metres squared, where m is the mass of the craft in the maximum
S LDC LDC
load condition, expressed in kilograms
Note 1 to entry: The reference sail area, A , is defined in ISO 8666:2016.
s
3.3
non-sailing craft
craft for which the primary means of propulsion is other than by wind power, having a reference
2/3
sail area A < 0,07(m ) , expressed in metres squared, where m is the mass of the craft in the
S LDC LDC
maximum load condition, expressed in kilograms
Note 1 to entry: The reference sail area, A , is defined in ISO 8666:2016.
s
3.4
reference waterline
W
L
level of the water on the hull in the fully loaded, ready-for-use condition
Note 1 to entry: The fully loaded, ready-for-use condition is defined in ISO 8666:2016.
3.5
heeled waterline
level of the water on the hull in the fully loaded, ready-for-use condition when the craft is inclined to:
— an angle of 7° for non-sailing craft and multihulls; or
— the level of the sheer line amidships or an angle of 30°, whichever is lower, for monohull sailing craft
Note 1 to entry: The fully loaded, ready-for-use condition is defined in ISO 8666:2016.
3.6
recess
volume open to the air that can retain water within the range of loading conditions and
corresponding trims
EXAMPLE Cockpits, wells, open volumes or areas bounded by bulwarks or coamings.
Note 1 to entry: Where fitted with closure device(s) according to ISO 12216:2020, cabins, shelters or lockers are
not recesses.
Note 2 to entry: A recess can be composed of several recesses connected together.
Note 3 to entry: Cockpits that are open to the sea are considered as recesses. Flush decks without bulwarks or
coamings are not recesses.
3.7
cockpit
recess (3.6) intended for the accommodation of people
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
3.8
watertight recess
recess (3.6) that satisfies the watertightness and sill (3.24) height requirements of this document, but
not the drainage requirements
3.9
quick-draining recess
recess (3.6) with characteristics and draining capacity that satisfy all the requirements of this document
for one or several design categories
Note 1 to entry: According to its characteristics, a recess can be considered as quick-draining for one design
category, but not for a higher category.
Note 2 to entry: The term "quick-draining" has been chosen to differentiate from the common understanding
term "self-draining", where water can be drained overboard in certain conditions, but without a specified
draining speed, height of bottom or sill, etc.
3.10
recess open to the sea
recess (3.6) where the aft and/or side boundaries are open to the outside of the craft, with a recess
retention height (3.21) equal to zero
Note 1 to entry: Figure C.1 c) gives an example of a recess open to the sea.
3.11
recess bottom
lowest surface of the recess (3.6), where water collects before being drained
Note 1 to entry: The recess bottom can have several levels.
3.12
recess bottom height
H
B
height of the recess bottom (3.11) above the waterline, the craft being upright, at rest and fully loaded
3.13
minimum recess bottom height
H
B min
minimum value of the recess bottom height (3.12) required by this document
3.14
single-bottom recess
recess (3.6) where the bottom has only one level
Note 1 to entry: A single-bottom recess fitted with a foot basin (3.31) is considered as a multi-bottom recess (3.15).
3.15
multi-bottom recess
recess (3.6) where the bottom has more than one level
3.16
bridge deck
area in the proximity of the companionway (3.23) opening and above the recess bottom (3.11), on which
people normally step before entering the accommodation
3.17
interior
inside the craft's watertight envelope
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
3.18
watertightness degree
degree of watertightness
capacity of an appliance (3.20) or fitting to resist ingress of water, according to the conditions of
exposure to water
Note 1 to entry: See Table 1 for a definition of the four watertightness degrees.
Table 1 — Definitions of the degrees of watertightness
Degree of watertightness: Definition
1 (waterproof) Constructed to withstand continuous immersion
Provides protection against the effects of continuous immersion in water
2 (watertight) Constructed to prevent ingress of water
Provides protection against the effects of temporary immersion in water
3 (weathertight) Constructed to minimize seepage
Provides protection against splashing water
4 (spraytight) Provides protection against waterdrops falling at an angle of up to 15° from the
vertical
NOTE Test procedures for watertightness degrees are provided in ISO 12216:2020.
3.19
downflooding opening
opening in the hull or deck (including the edge of a recess) that might admit water into the interior or
bilge of a craft, or into a recess
Note 1 to entry: Those excluded by ISO 12217 (all parts):2015 are not considered in this document.
3.20
appliance
device used to cover an opening in the hull, deck or superstructure of a craft
EXAMPLE Windows, portlights, hatches, deadlights, doors, sliding appliances, escape hatches, washboard,
compass, ventilation grids, loudspeakers, engine control panel, etc.
Note 1 to entry: They can be fixed appliances or opening appliances.
3.21
recess retention height
h
C
height of water in a recess (3.6), when the craft is upright and at design trim assuming that all gates,
2
doors or drainage openings are sealed, at which the overflow area is greater than 0,005 L B (m )
H H
Note 1 to entry: The design trim is in maximum load condition as defined in ISO 8666:2016.
Note 2 to entry: When h is less than 0,10 m, it is taken as equal to 0,0 m.
c
3.22
drain
outlet of the recess (3.6) enabling water contained to be discharged overboard by gravity
EXAMPLE A pipe discharging overboard above or below waterline; a part of the recess allowing direct
discharge overboard; scuppers and freeing port.
3.23
companionway
opening intended for crew access to the accommodation and fitted with an opening appliance (3.20)
Note 1 to entry: The opening appliance can be a door, a hatch; vertical, horizontal, etc.
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
Note 2 to entry: There can be several companionways.
3.24
sill
barrier above which water in the recess (3.6) can enter companionway (3.23) openings and downflood
the craft
EXAMPLE Hatches of cockpit companionways.
3.25
fixed sill
sill (3.24) that is a fixed, integral and permanent part of the recess (3.6)
3.26
semi-fixed sill
opening appliance (3.20), movable but permanently installed on the craft that, when in place, constitutes
a sill (3.24) higher than the fixed part of the sill
EXAMPLE Hatches, sliding sills, but excluding washboards.
Note 1 to entry: A lanyard is not regarded as a permanent attachment.
Note 2 to entry: Sliding or hinged doors are considered as a mobile part of a semi-fixed sill.
3.27
washboard
opening appliance (3.20) for companionway (3.23) openings made of several mobile boards sliding in
a rabbet that, when closed, are stacked one on top of each other, and located above the minimum sill
height (3.29)
Note 1 to entry: This is a frequent device on sailing monohulls; boards are added as the weather worsens.
3.28
sill height
h
S
minimum vertical distance from the top of the sill (3.24) to the closest part of the recess (3.6) bottom
Note 1 to entry: See Figure 1.
3.29
minimum sill height
h
S min
minimum value of the sill height (3.28) required by this document
3.30
recess volume
V
C
volume of water that can be contained in a recess (3.6) before discharge
Note 1 to entry: It is the maximum volume, considering any combination of movable coamings, etc., measured
from the recess bottom (3.11) up to the recess retention height (3.21), assuming that all opening appliances (3.20)
and drains (3.22) are closed.
3.31
foot basin
specific recess (3.6) that satisfies the requirements of 10.3 of this document, located between a recess
and a companionway (3.23) opening, and having a lower bottom than the surrounding recess
4 Symbols
Table 2 gives the main symbols used in this document, with their meaning and unit.
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
Table 2 — Main symbols used in this document
Symbol Meaning Unit
B Beam of hull as defined by ISO 8666:2016 m
H
F Freeboard amidships as defined by ISO 8666:2016 m
M
h Recess retention height m
C
h Sill height m
S
h Minimum sill height m
S min
H Recess bottom height above waterline m
B
H Minimum recess bottom height above waterline m
B min
k Design category factor —
DC
L Length of hull as defined by ISO 8666:2016 m
H
3
V Recess volume m
C
t Maximum allowable draining time min
max
t Reference draining time min
ref
d Drain diameter mm
NOTE Heights measured above the recess bottom have symbols beginning with h, whereas heights
measured above waterline have symbols beginning with H.
5 General
5.1 Loading and measurement conditions
Unless otherwise specifically stated in the text:
— the craft is in fully loaded, ready-for-use condition as defined in ISO 8666:2016;
2 3
— lengths and heights are measured in m, areas in m , volumes in m , time in min and/or s;
— measurements or calculations shall be made with the craft upright and at rest in calm water.
5.2 Requirements for watertight and quick-draining recesses
Table 3 summarizes the relevant clauses applicable to watertight and quick-draining recesses.
Table 3 — Relevant clauses for a recess to qualify as watertight or quick-draining
“Quick-draining” recess
Requirements Watertight recess
Open to the sea Reduced risk of
Others
(3.10) flooding (7.2)
Watertightness 6.1 6.2 6.2 6.2
Companionway sill None Clause 7 Clause 7 None
Height of recess bottom None Clause 8 Clause 8 Clause 8
Drainage None Clause 9 or 10 None None
Strength of appliances ISO 12216:2020 ISO 12216:2020 ISO 12216:2020 ISO 12216:2020
6 Watertightness requirements
6.1 Watertightness requirements for watertight recesses
In watertight recesses, all surfaces and appliances shall have a degree of watertightness 1 up to a
height of h .
C
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
6.2 Watertightness requirements for quick-draining recesses
All surfaces shall have a degree of watertightness 1.
The degree of watertightness of appliances installed in the surface of the quick-draining recess shall be
as specified in Table 4.
Table 4 — Degrees of watertightness of appliances
a
Location of appliances in the recess Degree of watertightness
appliance on bottom and sides up to h 2
S min
appliance between h and 2 h 3
S min S min
appliance above 2 h 4
S min
NOTE 1 On engine ventilation openings installed in a recess, a watertightness assessment can be performed using the total
arrangement of exterior grid and internal ducts or swan’s neck of the appliance, with material and connections sufficient to
withstand the associated head of pressure.
NOTE 2 Additional requirements can be specified in other International Standards, such as ISO 12217 (all parts):2015.
a
h is defined in Table 5, the local sill height and h being measured as required by 7.3
S min S min
Opening appliances covering downflooding openings and installed on the surfaces of a quick-draining
recess shall be secured in the closed position by a manually operated mechanical positive device.
7 Requirements for companionway sills
7.1 Companionway sills
Any companionway inside the limits of the recess and those located within an area extending 0,6 m
outside of the recess boundary shall comply with the requirements of this Clause (see Figure 1).
Key
1 sill height
2 front companionway door on bulkhead
3 aft companionway hatch on deck
Figure 1 — Sills considered and sill height measurement
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
7.2 Quick-draining recess with a reduced risk of flooding
A quick-draining recess with a reduced risk of flooding does not require a sill for any companionway
opening if it complies with the following criteria:
— the craft is of a fully enclosed type according to ISO 12217 (all parts):2015;
— the recess is open to the sea, as defined in 3.10 of this document;
— all of the recess is located aft of the mid hull length of the craft;
— companionway(s) is(are) installed on the rear face of a superstructure;
— it has the lowest point of the companionway(s) opening higher than [(L /17) + h ] above the
h S min
reference waterline;
— companionway opening appliance(s) is(are) permanently installed, enabling immediate closure.
7.3 Sill height measurement
The sill height is the lowest height of the companionway, as defined in 3.28.
The sill height shall be measured vertically from the adjacent closest point of the recess bottom to the
lowest point of the upper sill edge (see Figure 1).
If a multi-bottom recess is fitted with a foot basin complying with the foot basin requirements of 10.3,
the sill height shall be measured from the foot basin bottom; otherwise the sill height shall be measured
from the closest recess bottom
7.4 Minimum companionway sill height for quick-draining recesses
Table 5 specifies the requirements regarding minimum companionway sill height for quick-draining
recesses.
These requirements do not apply to quick-draining recesses with a reduced risk of flooding.
Where a semi-fixed sill is fitted, the height of the fixed part shall be at least (h /2).
S min
Table 5 — Minimum companionway sill height, h , for quick-draining recesses
S min
Dimensions in meters
Sailing monohulls Non-sailing craft and sailing multihulls
Design
category
minimum sill height, h minimum sill height, h
S min S min
A 0,30 0,20
B 0,25 0,15
C 0,15 0,10
D 0,05 0,05
NOTE The above requirements may be raised by other International Standards such as ISO 12217 (all parts):2015.
8 Height of recess bottom above waterline for quick-draining recesses
Table 6 specifies the minimum recess bottom height, H , above reference waterline, for quick-
B min
draining recesses.
For a single-bottom recess, H is measured at the centre of the surface of the bottom.
B
For a multi-bottom recess, H is measured at the centre of the surface of the lowest bottom.
B
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oSIST prEN ISO 11812:2023
ISO 11812:2020(E)
Table 6 — Minimum height, H , of the recess bottom above reference waterline
B min
Dimensions in meters
Design category H
B min
A 0,150
B 0,100
C 0,075
D 0,050
NOTE Greater heights than these minimum values may be required to fulfil the
maximum acceptable draining time according to Clauses 9 and 10.
9 Quick-draining recesses — Single bottom recess drainage
9.1 Drainage general requirements
Drainage shall only be by gravity.
If there are mobile parts allowing openings in the recess boundary, this requirement shall be verifi
...
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