prEN ISO 12217-2

SLOVENSKI STANDARD
01-marec-2026
Mala plovila - Stabilnost in ocena vzgona ter kategorizacija - 2. del: Jadrnice
(ISO/DIS 12217-2:2026)
Small craft - Stability and buoyancy assessment and categorization - Part 2: Sailing
boats (ISO/DIS 12217-2:2026)
Kleine Wasserfahrzeuge - Festlegung und Kategorisierung von Querstabilität und
Auftrieb - Teil 2: Segelboote (ISO/DIS 12217-2:2026)
Petits navires - Évaluation et catégorisation de la stabilité et de la flottabilité - Partie 2:
Bateaux à voiles (ISO/DIS 12217-2:2026)
Ta slovenski standard je istoveten z: prEN ISO 12217-2
ICS:
47.080 Čolni Small craft
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 12217-2
ISO/TC 188
Small craft — Stability and
Secretariat: SIS
buoyancy assessment and
Voting begins on:
categorization —
2026-01-15
Part 2:
Voting terminates on:
2026-04-09
Sailing boats
Petits navires — Évaluation et catégorisation de la stabilité et de
la flottabilité —
Partie 2: Bateaux à voiles
ICS: 47.080
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
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STANDARDS MAY ON OCCASION HAVE TO
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RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION.
Reference number
ISO/DIS 12217-2:2026(en)
DRAFT
ISO/DIS 12217-2:2026(en)
International
Standard
ISO/DIS 12217-2
ISO/TC 188
Small craft — Stability and
Secretariat: SIS
buoyancy assessment and
Voting begins on:
categorization —
2026-01-15
Part 2:
Voting terminates on:
2026-04-09
Sailing boats
Petits navires — Évaluation et catégorisation de la stabilité et de
la flottabilité —
Partie 2: Bateaux à voiles
ICS: 47.080
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
© ISO 2026
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
BE CONSIDERED IN THE LIGHT OF THEIR
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POTENTIAL TO BECOME STANDARDS TO
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or ISO’s member body in the country of the requester.
NATIONAL REGULATIONS.
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TO SUBMIT, WITH THEIR COMMENTS,
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NOTIFICATION OF ANY RELEVANT PATENT
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Website: www.iso.org
Published in Switzerland Reference number
ISO/DIS 12217-2:2026(en)
ii
ISO/DIS 12217-2:2026(en)
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols .13
5 General .15
5.1 Sailing or non-sailing . 15
5.2 Requirements to be applied . 15
5.3 Assignment of design category/categories .18
5.3.1 Meaning of the design categories .18
5.4 Determining maximum load and crew limit .19
5.5 Location of Masses .19
5.5.1 Asymmetric ballast .19
5.6 Variation in input parameters .19
5.7 Test options . 20
6 Tests, calculations and requirements .20
6.1 Openings . 20
6.1.1 Process for assessing openings . 20
6.1.2 Preparation to be done prior to classifying openings .21
6.1.3 Classification of openings . .21
6.2 Downflooding height . 23
6.2.1 Requirements . 23
6.2.2 Test . . .24
6.3 Downflooding angle . 25
6.3.1 Requirements . 25
6.3.2 Assessment . 25
6.4 Capsize-recovery . 25
6.5 Detection and removal of water . .27
6.6 Minimum righting energy . 28
6.7 Angle of vanishing stability . 28
6.7.1 General . 28
6.7.2 Requirement . 28
6.8 Stability index (STIX) . 29
6.8.1 Method . . 29
6.8.2 Dynamic stability factor (FDS) . 29
6.8.3 Inversion recovery factor (FIR) . 29
6.8.4 Knockdown recovery factor (FKR) . 30
6.8.5 Displacement-length factor (FDL) . 30
6.8.6 Beam-displacement factor (FBD) . 30
6.8.7 Wind moment factor (FWM) .31
6.8.8 Downflooding factor (FDF) .31
6.8.9 Calculation of the stability index (STIX) .32
6.9 Knockdown-recovery .32
6.10 Wind stiffness . 33
6.10.1 General . 33
6.10.2 Practical test . 33
6.10.3 Compliance by calculation . 35
6.10.4 Requirements . 35
6.11 Flotation requirements .37
6.12 Stability information for multihull craft .37
6.13 Safety signs for multihull craft . 38
6.14 Bare poles factor for multihull craft. 39

iii
ISO/DIS 12217-2:2026(en)
6.15 Rolling of multihull craft in breaking waves . 39
6.16 Pitchpoling of multihull craft . 40
6.17 Diagonal stability of multihull craft . 40
6.18 Buoyancy when inverted for multihull craft . 40
6.19 Escape after inversion of multihull craft .41
Annex A (informative) Flowchart for determining downflooding openings .44
Annex B (normative) Full method for required downflooding height . 47
Annex C (normative) Methods for calculating downflooding angle .49
Annex D (normative) Determining the curve of righting moments .51
Annex E (normative) Safety signs .54
Annex F (normative) Method for calculating reserve of buoyancy after inversion or swamping .55
Annex G (normative) Flotation material and elements .57
Annex H (normative) Information for the craft’s owner’s manual .59
Annex I (normative) Determination of safe wind speed information .63
Annex J (normative) Determination of longitudinal righting characteristics .66
Annex ZA (informative) Relationship between this European Standard and the essential
requirements of Directive 2013/53/EU aimed to be covered.69
Bibliography .71

iv
ISO/DIS 12217-2:2026(en)
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 World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 188, Small Craft, in collaboration with the
European Committee for Standardization (CEN) Technical Committee CEN/TC 464, Small Craft, in accordance
with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 12217-2:2015), of which it constitutes a minor
revision. The main changes are as follows:
— the Normative references have been updated;
— the term "fully/partially enclosed boat" has been changed to "degree of deck protection" which has 2
possible categories (in part 2): fully protected or unprotected;
— the sheerline has been defined to account for rounded deck edges;
— the definition of downflooding openings has been entirely re-written for clarity, but the fundamental
concept of what is and is not a downflooding opening remains unchanged;
— the Recess Size calculation has been removed, along with all references to recess retention height;
— The distinction between catamarans and trimarans has been replaced with multihulls.
— The alternative estimation method for form stable monohulls in category B to assess the angle of
vanishing stability has been removed;
— in Annex J, the calculation worksheets have been updated;
— minor editorial changes throughout the document.
A list of all parts in the ISO 12217 series can be found on the ISO website.
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.

v
ISO/DIS 12217-2:2026(en)
Introduction
This document enables the determination of limiting environmental conditions for which an individual craft
has been designed.
It enables the craft to be assigned to a design category appropriate to its design and maximum load. The
design categories used align with those in the Recreational Craft Directive of the European Union, EU
Directive 2013/53/EU.
Annex J provides worksheets to assist in the systematic assessment of a craft according to this document.

vi
DRAFT International Standard ISO/DIS 12217-2:2026(en)
Small craft — Stability and buoyancy assessment and
categorization —
Part 2:
Sailing boats
CAUTION — CAUTION — Compliance with this document does not guarantee total safety or total
freedom of risk from capsize or sinking.
NOTE — The electronic file of this document contains colours which are considered to be useful for
the correct understanding of the document. Users should therefore consider printing this document
using a colour printer.
1 Scope
This document specifies methods for evaluating the stability and buoyancy of intact (i.e. undamaged) craft.
The flotation characteristics of craft susceptible to swamping are also encompassed.
The evaluation of stability and buoyancy properties using this document will enable the craft to be assigned
to a design category (A, B, C or D) appropriate to its stability and buoyancy characteristics.
This document is principally applicable to small craft propelled primarily by sail (even if fitted with an
auxiliary engine) of 2,5 m up to and including 24 m hull length.
In relation to habitable multihulls, this document includes assessment of susceptibility to inversion,
definition of viable means of escape and requirements for inverted flotation.
This document excludes:
— inflatable and rigid-inflatable craft covered by the ISO 6185 series, except for references made in the
ISO 6185 series to specific clauses of the ISO 12217 series;
— aquatic toys;
— gondolas and pedalos;
— surfboards including sailing surfboards; and
— hydrofoils and foil stabilized craft when not operating in the displacement mode.
NOTE Displacement mode means that the craft is only supported by hydrostatic forces.
It does not include or evaluate the effects on stability of towing, fishing, or lifting operations or dynamic
stability of high speed arecraft, which need to be separately considered if appropriate.
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.
ISO 2896, Rigid cellular plastics — Determination of water absorption

ISO/DIS 12217-2:2026(en)
ISO 3864-1, Graphical symbols — Safety colours and safety signs — Part 1: Design principles for safety signs and
safety markings
ISO 8666, Small craft — Principal data
ISO 10240, Small craft — Owner's manual
ISO 14946, Small craft — Maximum load capacity
ISO 15085, Small craft — Protection from falling overboard and means of reboarding
ISO 8666:2020, Small craft — Principal data
ISO 8666:2020, Small craft — Principal data
ISO 11812, Small craft — Watertight or quick-draining recesses and cockpits
ISO 12216, Small craft — Windows, portlights, hatches, deadlights and doors — Strength and watertightness
requirements
ISO 12217-1:2022, Small craft — Stability and buoyancy assessment and categorization — Part 1: Non-sailing
boats of hull length greater than or equal to 6 m
ISO 15083, Small craft — Bilge-pumping systems
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
NOTE The meanings of certain symbols used in the definitions are given in Clause 4.
3.1
air container
container made of stiff material, and not integral with the hull or deck structure
3.2
air tank
tank made of hull construction material, and integral with hull or deck structure
3.3
angle of vanishing stability
ϕ
V
angle of heel nearest the upright (other than upright) in the appropriate loading condition at which the
transverse stability righting moment is zero
Note 1 to entry: Where a craft has recesses which are not quick-draining, ϕ is to be taken as the downflooding angle
V
(3.8) to these recesses, unless the loss of buoyancy due to such recesses is fully accounted for in determining ϕ .
V
Note 2 to entry: Angle of vanishing stability is expressed in degrees.
3.4
beam between hull centres
B
CB
on catamaran (3.9) and trimaran (3.52) craft, the transverse distance between the centres of buoyancy of
the outer hulls
Note 1 to entry: Beam between hull centres is expressed in metres.

ISO/DIS 12217-2:2026(en)
3.5
beam of hull
B
H
maximum beam of the hull using the method of ISO 8666; for multihull craft, maximum beam across the
outer hulls
Note 1 to entry: Beam of hull is expressed in metres.
3.6
beam waterline
B
WL
greatest beam measured according to ISO 8666 at the waterline in calm water which, for multihull craft,
is the sum of the maximum waterline beams of each of the hulls, the craft being upright, in the appropriate
loading condition and at design trim
Note 1 to entry: Beam waterline is expressed in metres.
3.7
calculation wind speed
v
W
wind speed to be used in calculations
Note 1 to entry: Calculation wind speed is expressed in metres per second or in knots.
3.8
capsize
event when a craft reaches any heel angle from which it is unable to recover to equilibrium near the upright
without intervention
3.9
catamaran
craft with two main load-bearing hulls
EXAMPLE Craft with a centreline or bridge-deck nacelle which supports less than 30 % of the mass in the
maximum load condition are considered to be catamarans. Proas are asymmetric catamarans.
3.10
companionway
opening intended for crew access to the accommodation and fitted with an opening appliance.
Note 1 to entry: The opening appliance can be a door, a hatch; vertical, horizontal, etc.
Note 2 to entry: There can be several companionways.
3.11
craft
small craft
recreational craft, and other watercraft using similar equipment, of up to 24 m length of hull (L
H
Note 1 to entry: The length of hull (L ) is defined in ISO 8666:2020.
H
[SOURCE: ISO 8666:2020, 3.15, modified — Note 1 to entry has been added]
3.12
crew
collective description of all persons onboard a craft
3.13
crew limit
CL
maximum number of persons (with a mass of 75 kg each) used when assessing the design category

ISO/DIS 12217-2:2026(en)
3.14
degree of deck protection
measure of the extent of a watercraft’s watertight envelope, above the horizontal projection of the sheerline
or plan view.
Note 1 to entry: In the context of this standard, protection is provided by a combination of the following:
— watertight deck and superstructure, and/or
— quick-draining recesses complying with ISO 11812,and/or
— watertight recesses complying with ISO 11812 with a combined volume of less than (L B F )/40, and
H H M
— all appliances have their degree of watertightness in accordance with ISO 12216;
— outboard engine wells;
— rigid covers.
Note 2 to entry: Requirements for openings in protected areas are given in ISO 12216.
Note 3 to entry: Bilge pumps do not provide protection.
3.14.1
fully protected
craft on which protection extends over the full area of the plan view
3.14.2
partially protected
This definition is used only in part 1 of this standard.
3.14.3
unprotected
craft which are not fully protected (3.14.1)
3.15
design category
description of the maximum sea and wind conditions for which a craft is assessed to withstand
Note 1 to entry: See also 5.3.1.
3.16
design trim
longitudinal attitude of a craft when upright, with crew, fluids, stores and equipment in designated positions
Note 1 to entry: Crew are assumed to be either standing or seated on working deck (as defined by ISO 15085) and/
or interior of the craft. Crew and gear are assumed to be positioned in a manner most likely to provide a favourable
assessment result, provided that such positions are consistent with the proper operation of the craft.
3.17
displacement volume
V
D
volume of displacement of the craft that corresponds to the appropriate loading condition, taking the density
of water as 1 025 kg/m
Note 1 to entry: Displacement volume is expressed in cubic metres.

ISO/DIS 12217-2:2026(en)
3.18
downflooding angle
ϕ
D
angle of heel at which downflooding openings apart from those excluded in Table 4, become immersed, when
the craft is in calm water and in the appropriate loading condition at design trim and heel, measured to the
first downflooding opening which might be within pipes or ducts inside the hull
Note 1 to entry: Downflooding angle can be determined using either of the methods in Annex C.
Note 2 to entry: Where openings are not symmetrical about the centreline of the craft, the case resulting in the
smallest angle is used.
Note 3 to entry: The following are specifically considered:
— ϕ is the downflooding angle to any downflooding opening;
D
— ϕ is the angle of heel at which openings which are not marked “KEEP SHUT WHEN UNDER WAY” having a
DA
combined total area, expressed in square centimetres (cm ), greater than the number represented by 1,2L B F
H H M
first become immersed;
— ϕ is the downflooding angle at which recesses which are not quick-draining begin to fill with water;
DC
— ϕ is the downflooding angle at which any main access hatch (i.e. having an opening area greater than 0,18 m
DH
each) giving direct access to the main open air helm position first begins to become immersed.
Note 4 to entry: Downflooding angle is expressed in degrees.
3.19
downflooding height
h
D
lowest height above the waterline to any downflooding opening when the craft is upright in calm water and
in the maximum load condition, measured to the first downflooding opening which might be within pipes or
ducts inside the hull
Note 1 to entry: Downflooding height is expressed in metres.
Note 2 to entry: See Figure C.1.
3.20
downflooding opening
aperture, whether covered by a appliance or not, in the watertight envelope of a craft that is not listed in 6.1.3.
3.21
draught of canoe body
T
C
draught of the main buoyant part of the hull(s) below the waterline, as defined in ISO 8666, the craft being
upright in the appropriate loading condition and at design trim
Note 1 to entry: In cases where the keel form cannot be easily separated from that of the hull, the canoe body draught
shall be determined by the intersection of the least steep tangent to the hull surface with the centreline plane.
Note 2 to entry: Draught of canoe body excludes appendages such as rudders or skegs, and is expressed in metres.
3.22
empty craft condition
empty craft including fittings and equipment as listed below but excluding all craft manufacturer offered
optional equipment:
a) structure: comprising all the structural parts, including any fixed solid ballast keel and/or drop keel/
centreboard/daggerboard(s) and rudder(s);
b) ballast: any fixed solid ballast installed;

ISO/DIS 12217-2:2026(en)
c) internal structure and accommodation: bulkheads and partitions, insulation, lining, built-in furniture,
flotation material, windows, hatches and doors, permanently installed mattresses and upholstery
materials;
d) permanently installed engine(s) and fuel system: comprising inboard engine(s), including all supplies
and controls as needed for their operation, permanently installed fuel systems, including tanks;
e) fluids in permanently installed systems: residual working fluids as needed for their operation (see
examples below), but excluding contents of fluid ballast systems and tanks, and main storage tanks
(which are included in maximum load);
EXAMPLE Fluids in hot or cold water, fuel, lubricating or hydraulic oil systems.
f) internal equipment, including:
1) all items of equipment permanently attached to the craft, e.g. tanks, toilet system(s), water transfer
equipment;
2) bilge pumping system(s), cooking and heating devices, cooling equipment, ventilation system(s);
3) electrical installation and equipment, including permanently installed batteries mounted in the
position intended by the builder;
4) fixed navigational and electronic equipment;
5) fixed firefighting equipment, where fitted;
g) external equipment, including:
1) all permanently attached standard or specified deck fittings, e.g. guardrails, pulpits and pushpits,
bowsprits and their attachments, bathing platforms, boarding ladders, steering equipment, winches,
sprayhood(s);
2) awning(s), cockpit tables, gratings, signal mast(s), where fitted;
3) mast(s), boom(s), spinnaker poles and other pole(s), standing and running rigging, in the stowed
position ready for use; all standing and running rigging in place
Note 1 to entry: The mass in the empty craft condition is denoted by m and is expressed in kilograms.
EC
3.23
essential safety equipment
loose equipment considered essential to the safe operation of the craft, which shall include liferaft(s) large
enough to hold the crew limit on craft of design categories A and B and for craft of design categories C and D
longer than 6 meters
Note 1 to entry: Examples of essential safety equipment are: distress flares and rockets, lifebuoy with light and battery,
first aid box, wire cutters for standing rigging, lifejackets, safety harnesses and lines, portable firefighting equipment,
flashlight, binoculars, radio (e.g. VHF), ball and cone visual signals, charts, navigational publications.
Note 2 to entry: Quantities carried may vary according to the size of craft, design category and crew limit.
Note 3 to entry: As a guide, the mass allowed for essential safety equipment but excluding any liferaft(s) should not be
less than 3L (kg).
H
Note 4 to entry: The mass of yachting liferafts varies from approximately 12 + 2CL (kg) to double this, according to
specification.
3.24
flotation element
element which provides buoyancy to the craft and thus influences the flotation characteristics

ISO/DIS 12217-2:2026(en)
3.25
freeboard amidships
F
M
distance of the sheerline or deck above the waterline at L /2 measured according to ISO 8666,the craft
WL
being upright, in the appropriate loading condition and at design trim
Note 1 to entry: Freeboard amidships is expressed in metres.
Note 2 to entry: Where no loading condition is specified, maximum load condition should be assumed.
3.26
habitable
A craft is habitable if it has at least one space surrounded by permanent structure in which there is provision
for any of the following activities:
— sleeping;
— cooking;
— eating;
— washing/toilet;
— navigation;
— steering
.
Note 1 to entry: A craft is considered to be “habitable” if a fabric closure is used instead of a rigid door, or the cabin has
fabric sides.
Note 2 to entry: The following are not considered to render a craft “habitable”:
— a cockpit tent, or
— an open-sided cuddy intended to provide limited protection from spray, provided it is not fitted with fabric closures
all round.
Note 3 to entry: Locations used for sleeping have minimum dimensions of 1,5 m diagonal length, 0,4 m width at the
widest point, and with a minimum headroom of 0,4 m over the length. The cabin sole and compartments designated by
the builder to be used exclusively for storage and referenced in the owner’s manual are not included.
3.27
heeled waterline
level of the water on the hull in the fully loaded condition (m ) when the craft is inclined to—
LDC
a) 7° for motor craft and sailing multihulls, or
b) 30° or immersion of the sheerline, whichever occurs first, for monohull sailing craft.
3.28
inclining experiment
method by which the vertical position of the centre of gravity (VCG) of a craft can be determined
Note 1 to entry: The VCG, together with a knowledge of the shape of the hull (the lines plan) and the position of the
waterline in a known loading condition, enable all the intact stability parameters to be calculated.
Note 2 to entry: A full description of how to conduct an inclining experiment is given in standard naval architecture
[1] [2]
textbooks, e.g. References ASTM F1321-92 and .

ISO/DIS 12217-2:2026(en)
3.29
inflated bag
bag made of flexible material, not integral with hull or deck, accessible for visual inspection and intended
always to be inflated when the craft is being used
Note 1 to entry: Bags intended to be inflated automatically when immersed (e.g. at the masthead as a means to prevent
inversion) are not regarded as flotation elements.
3.30
inversion
event when a craft becomes upside down
3.31
knockdown
event when a craft reaches a heel angle sufficient to immerse the masthead, and from which it may or may
not recover without intervention
3.32
length of hull
L
H
length of the hull measured according to ISO 8666
Note 1 to entry: Length of hull is expressed in metres.
3.33
length of waterline
L
WL
waterline length measured according to ISO 8666 when the craft is upright in calm water, in the appropriate
loading condition and at design trim
Note 1 to entry: For multihull craft, L relates to that of the longest individual hull.
WL
Note 2 to entry: Length of waterline is expressed in metres.
3.34
light craft condition
empty craft condition plus standard equipment (3.49) plus removable ballast (whether solid or liquid)
when supplied and/or intended by the manufacturer to be carried when the craft is afloat, with elements
positioned as follows:
a) where provision is made for propulsion by outboard engine(s) of more than 3 kW, the heaviest engine(s)
recommended for the craft by the manufacturer is(are) mounted in the working position(s);
b) where batteries are fitted, they are mounted in the position intended by the builder, and if there is no
specific stowage provided for batteries, the mass of one battery for each engine over 7 kW is allowed for,
and located within 1,0 m of the engine location;
c) sails as considered for the reference sail area , onboard and rigged ready for use, but not hoisted, e.g.
mainsail on boom, roller furling sails furled, hanked foresails on stay stowed on foredeck
Note 1 to entry: The mass in the light craft condition is denoted by m and is expressed in kilograms.
LC
Note 2 to entry: Water ballast in tanks which are symmetrical about the centreline and which are intended by the
builder to be used for variable asymmetric ballasting while underway, is excluded.
Note 3 to entry: Upwind sails are those used to compute the standard sail area (3.50)

ISO/DIS 12217-2:2026(en)
3.35
loaded arrival condition
craft in the maximum load condition minus 85 % of the maximum capacity of fixed or portable storage tanks
for fuel, oils and drinking water, and minus 90 % of edible stores, but including the worst combination of
optional fittings or equipment with respect to stability
Note 1 to entry: In this condition, tanks have 10 % of their maximum capacity remaining.
Note 2 to entry: The mass in the loaded arrival condition is denoted by m and is expressed in kilograms.
LA
Note 3 to entry: Unless otherwise required, variable position elements (e.g. canting keels, movable solid ballast, tilting
masts) are positioned symmetrically about the centreline of the craft.
3.36
loaded waterline
waterline of the craft when upright in the maximum load condition
3.37
low density material
material with a specific gravity of less than 1,0 primarily incorporated into the craft to enhance the buoyancy
when swamped
3.38
maximum load
load which the craft is designed to carry in addition to the light craft condition, comprising:
— the crew limit at 75 kg each;
— the personal effects of the crew;
— stores and cargo (if any), dry provisions, consumable liquids;
— contents of all permanently installed storage tanks filled to 95 % of their maximum capacity, including
fuel, drinking water, black water, grey water, lubricating and hydraulic oil, bait tanks and/or live wells;
— ballast water at 100 % capacity;
— consumable liquids in portable tanks (drinking water, fuel) filled to 95 % of the maximum capacity;
— dinghy or other small craft intended to be carried aboard, and any outboard motor associated with them;
— liferaft(s) if carried in excess of the minimum required in essential safety equipment;
— non-edible stores and equipment normally carried on the craft and not included in the manufacturer’s
list of standard equipment, e.g. loose internal equipment and tools, spare parts, additional anchors or
sails, dinghy and outboard if carried aboard;
Note 1 to entry: Liferafts are not included in essential safety equipment for Categories C and D shorter than 6 m.
Note 2 to entry: As a guide, not less than 20 kg per person should be allowed for personal effects on habitable craft.
Note 3 to entry: As a guide, the mass of yachting liferafts varies from approximately 12 + 2CL (kg) to double this,
according to specification.
Note 4 to entry: Unless otherwise required, variable position elements (e.g. canting keels, movable solid ballast, tilting
masts) are positioned symmetrically about the centreline of the craft.
Note 5 to entry: Any centreboard or keel is in the raised position unless it can be fixed in the lowered position and an
appropriate instruction is given in the owner’s manual.
Note 6 to entry: The mass of maximum load is denoted by m and is expressed in kilograms.
ML
ISO/DIS 12217-2:2026(en)
3.39
maximum load condition
craft in the light craft condition with the maximum load added and the maximum mass of craft manufacturer
offered optional equipment and fittings so as to produce the design trim, the crew being in positions typically
used when the craft is underway
Note 1 to entry: The mass in the maximum load condition is denoted by m and is expressed in kilograms.
LDC
3.40
minimum operating condition
c
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