ISO 7462:1985

Shipbuilding - Principal ship dimensions - Terminology and definitions for computer applications

Defines terms for quantities used as input to, and output from, computer programs for shipbuilding. Establishes terminology and definitions also for derived non-dimensional coefficients used in describing ships' hulls and their hydrostatic conditions.

Construction navale — Dimensions principales des navires — Terminologie et définitions applicables au traitement par ordinateur

General Information

• Status: Published
• Publication Date: 20-Feb-1985
• ICS: 01.040.47 - Shipbuilding and marine structures (Vocabularies)
• ICS: 35.240.50 - IT applications in industry
• ICS: 47.020.01 - General standards related to shipbuilding and marine structures
• Technical Committee: ISO/TC 8/SC 8 - Ship design
• Drafting Committee: ISO/TC 8/SC 8 - Ship design
• Current Stage: 9093 - International Standard confirmed
• Start Date: 23-Dec-2022
• Completion Date: 13-Dec-2025

Overview

ISO 7462:1985 - Shipbuilding: Principal ship dimensions - Terminology and definitions for computer applications defines the standard vocabulary for dimensional and derived quantities used in ship design software and hydrostatic analysis. Intended as a reference for data input and output, the standard establishes clear meanings for reference lines and surfaces (baseline, load waterline, perpendiculars, midships, stations), dimensional quantities (breadth, depth, draught, length, displacement) and the non‑dimensional coefficients derived from them that describe hull form and hydrostatic condition. The document is published in English and French and was prepared by ISO/TC 8 (Shipbuilding and marine structures).

Key topics

• Reference lines & surfaces - baseline, designed (Summer) load waterline, perpendiculars, midships, waterplane and maximum section. These define the coordinate axes and datums used in calculations.
• Dimensional quantities - consistent definitions for breadth (moulded vs extreme), depth, draught (moulded vs extreme; forward, amidships, aft), length (between perpendiculars, overall, waterline, submerged overall) and displacement (mass and volume).
• Non‑dimensional coefficients - terminology and definitions for coefficients derived from dimensional data that describe hull shape and hydrostatic behavior (used as inputs/outputs in naval architecture software).
• Computer application guidance - specifies that any additional dimensions or coefficients not covered by ISO 7462 must be defined explicitly in program input forms and output reports to avoid ambiguity.

Practical applications

ISO 7462:1985 is practical for anyone producing, exchanging or interpreting ship hull data between people and computer programs:

• Naval architects and hydrodynamicists - ensure consistent input/output terms when running hydrostatics, resistance, stability or strength analyses.
• Shipbuilders and designers - communicate principal dimensions and derived coefficients unambiguously across teams and suppliers.
• Software developers and data modelers - implement standardized field names and datums for shipbuilding applications, CAD/CAM and analysis tools.
• Classification societies and marine surveyors - reference consistent terminology for statutory, design and survey documentation.

Adopting ISO 7462 reduces data misinterpretation, improves interoperability between software systems, and supports accurate hydrostatic and form‑related calculations.

Related standards

Prepared by ISO/TC 8, ISO 7462 complements other shipbuilding terminology and measurement standards. When exchanging outputs that include terms outside ISO 7462, the standard requires those terms to be defined in the output documentation.

Standards Content (Sample)

International Standard
Norme internationale
INTERNATIONAL ORGANIZATION FOR STANDARDIZATIONWlEIKjJYHAPO~HAR OPrAHM3AUMR fl0 CTAHL\APTl43A~MLWORGANISATION INTERNATIONALE DE NORMALISATION
Shipbuilding - Principal ship dimensions - Terminology
and definitions for Computer applications
First edition - 1985-02-15
Construction navale - Dimensions principales des
navires - Terminologie et definitions applicables au
traitement par ordinateur
Premiere Edition - 1985-02-45
G-
\
UDWCDU 629.12.011.1 : 001.4 : 681.3
W
Ref. No./Rbf. no : ISO7462-1985 (E/F)
-
Descriptors : shipbuilding, ships,
dimensions, Computer applications, vocabulary. / Descripteurs :
construction navale, navire, dimension,
application de I’informatique, vocabulaire.
Price based on 8 pages/Prix bas6 sur 8 pages

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. Esch 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, govern-
mental and non-governmental, in liaison with ISO, also take part in the work.
Draft International Standards adopted by the technical committees are circulated to
the member bodies for approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 7462 was prepared by Technical Committee ISO/TC 8,
Shipbuilding and marine structures.
Avant-propos
L’ISO (Organisation internationale de normalisation) est une federation mondiale
d’organismes nationaux de normalisation (comites membres de I’ISO). L’elaboration
des Normes internationales est confiee aux comites techniques de I’ISO. Chaque
comite membre interesse par une etude a Ie droit de faire Partie du comite technique
cr& a cet effet. Les organisations internationales, gouvernementales et non gouverne-
mentales, en liaison avec I’ISO, participent egalement aux travaux.
Les projets de Normes internationales adoptes par les comites techniques sont soumis
aux comites membres pour approbation, avant leur acceptation comme Normes inter-
nationales par Ie Conseil de I’ISO. Les Normes internationales sont approuvees confor-
mement aux procedures de I’ISO qui requierent I’approbation de 75 % au moins des
comites membres votants.
La Norme internationale ISO 7462 a etc elaboree par Ie comite technique ISO/TC 8,
Construction navale et structures maritimes.
0 International Organkation for Standardkation, 1985 l
0 Organisation internationale de normalisation, 1985 0
Printed in Switzerland/ Imprimk en Suisse
ii
Contents
1 Scope and field of application .
2 Reference lines and surfaces .
3 Dimensional quantities .
4 Non-dimensional coefficients .
Figure . 6
Alphabetical indexes
English . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
French . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sommaire Page
1 Objet et domaine d’application . . . .
2 Lignes et surfaces de reference . . . .
3 Grandeurs dimensionnelles . . . . . . . 3
4 Coefficients sans dimension . . . . . . 5
Figure . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Index alphabktiques
Anglais. /
Francais . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
I
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INTERNATIONAL STANDARD
ISO 7462-1985 (E/F)
NORME INTERNATIONALE
Shipbuilding - Principal Construction navale -
ship dimensions - . Dimensions principales
des navires - Terminologie
Terminology and
et definitions applicables
definitions for Computer
au traitement par ordinateur
applications
1 Scope and field of application 1 Objet et domaine d’application
This International Standard defines terms for quantities used as La presente Norme internationale definit les termes relatifs aux
input to, and output from, grandeurs que I’on introduit dans les Programmes d’ordinateur
Computer programs for ship-
building. It establishes terminology and definitions for the main pour Ia construction navale, ou que I’on sort de ces program-
mes. Elle etablit une terminologie et des definitions des prin-
dimensional quantities and derived non-dimensional coeffi-
cients used in describing ships’ hulls and their hydrostatic con- cipales grandeurs dimensionnelles utilisees pour decrire les
ditions. carenes de navires et leurs conditions hydrostatiques, avec les
coefficients sans dimension qui en derivent.
NOTE - When dimensions and non-dimensional coefficients other
than those defined in this International Standard occur in Computer
NOTE - Si un ordinateur sort des dimensions ou des coefficients sans
output, the terminology shall be defined in the output document. Such
dimension autres que celles et ceux qui sont inclus dans Ia presente
terms shall also be defined when they appear on input data pro forma.
Norme internationale, les termes correspondants doivent etre definis
dans Ie document de sortie. Ces memes termes doivent egalement etre
definis s’ils apparaissent en donnees d’entree pro forma.
2 Lignes et surfaces de refhence (voir Ia figureI
2 Reference lines and surfaces (sec the figure)
2.1 ligne de base : Ligne situee dans Ie plan longitudinal de
2.1 baseline : A line in the longitudinal plane of symmetry of
the ship’s hull parallel to the designed Summer load waterline, symetrie de Ia coque du navire, parallelement a Ia ligne de flot-
taison au tirant d’eau d’ete, utilisee comme reference dans Ia
which is used as a datum in defining the heights of Points on
definition de Ia hauteur des Points de Ia coque et qui definit
the hull, and defines the primary axis of the coordinate System.
Preferably, it shall be positioned such that no Point on the I’axe primaire du Systeme de coordonnees. Elle doit, de prefe-
rence, etre placee de teile Sorte qu’aucun Point de Ia surface
moulded surface of the hull will lie below the baseline and shall
normally be defined to pass through the lowest Point on the hors membres de Ia coque ne se situe au-dessous d’elle et doit
normalement passer par Ie Point Ie plus bas de Ia surface hors
moulded surface between perpendiculars.
membres entre perpendiculaires.
2.2 hors tout: Terme utilise pour qualifier une dimension
2.2 extreme : Qualification of a dimension which is
measured to the outer surface of the structure or appendage, mesuree sur Ia surface exterieure de Ia structure ou de ses
as opposed to the moulded surface. accessoires, par Opposition a Ia surface hors membres.
Extreme dimensions are measured to the outside of non- Les dimensions hors tout sont mesurees sur I’exterieur des
accessoires non structuraux, tels que les divers types de defen-
structural appendages such as rubbing strakes or fenders and
include overhang of superstructure, deck erections, etc. ses, les debordements de superstructure, de Pont, etc.

ISO 7462-1985 (E/F)
23 loa d waterline: When not otherwise qual ified, this shall 23 ligne de flottaison en Charge : Sau f indication
con-
imply the 1 designed Summer load waterline. traire, designe Ia ligne de flottaison au
tirant d’eau d’ete.
As a reference iine it defines the intersection of the load En tant que reference, elle definit l’intersection entre Ia ligne
waterplane with the vertical plane through the ship’s d’eau en Charge et Ie plan vertical Passant par I’axe longitudinal
longitudinal centreline. The term may also be applied to the du navire. Le terme peut egalement s’appliquer a Ia courbe defi-
curve defining the intersection of the load waterplane with the nissant I’intersection entre Ia ligne d’eau en Charge et Ia surface
hull surface. de Ia coque.
2.4 maximum section: The transverse section of the hull 2.4 maitre couple : Section transversale de Ia coque ayant Ia
having the greatest immersed area to the designed Summer plus grande surface immergee par rapport a Ia ligne de flottai-
son au tirant d’eau d’ete.
load waterline.
2.5 midships : The Station midway between the after m ilieu : Couple
2.5 couple a mi-distance entre Ia perpendi-
perpendicular and the forward perpendicular. culaire arriere et Ia perpendicu Ia ire avant.
2.6 hors membres: Terme utilise pour qualifier une dimen-
2.6 moulded: Qualification of a dimension which is
measured to a moulded surface or line. sion mesuree par rapport a une surface ou a une ligne interieure
(hors membres).
A moulded surface is a defined reference surface.
Une surface hors membres est une surface de reference bien
definie.
A moulded fine is a curve or straight line which
lies in the
moulded surface
Une Eigne hors membres est
une courbe ou une ligne droite
appartenant a Ia surface hors membres.
The moulded surface of a ship’s hull is normally defined by lines
drawn to the inside of the plating in the case of a ship of con-
ventional metal construction. For ships of wood, glass- La surface hors membres d’une coque de navire se definit nor-
reinforced plastic, cement or other non-plated construction, it malement par des lignes tracees a I’interieur du borde pour les
usually refers to the outer surface of the hull. navires de construction metallique traditionnelle. Pour les navi-
res a coque en bois, en plastique renforce a Ia fibre de verre, en
Ciment ou en un autre materiau que Ia tole, il s’agit generale-
ment de Ia surface exterieure de Ia coque.
2.7 perpendicular: 2.7 perpendiculaire : Ligne droite perpendiculaire abaissee
A straight line perpendicular to the
designed Summer load waterplane of a ship through a fixed sur Ia ligne de flottaison au tirant d’eau d’ete d’un navire et pas-
Point, as stated by classification rules.
sant par un Point fixe specifie par les societes de classification.
2.7.1 after [aftl perpendicular (AP) : Through a fixed Point 2.7.1 perpendiculaire arriere (AP) : Perpendiculaire Passant
at the Stern, normally the after side of the rudder post or centre- par un Point fixe de Ia poupe, normalement sur Ie dos de I’etam-
bot ou sur I’axe de Ia meche de gouvernail pour les navires
line of rudder stock in ships without a rudder Post.
n’ayant pas d’etambot.
2.7.2 perpendiculaire avant (FP) : Perpendiculaire Passant
par un Point fixe de Ia proue, normalement a l’intersection de
I’avant de I’etrave avec Ia ligne de flottaison au tirant d’eau
d’ete.
28 . section: A vertical transverse Cross-section of the hull. 28 . coupe: Section verticale transversale de Ia coque.
2.9 Station: A defined Point on the longitudinal axis or
baseline of the ship. A plane normal to the baseline and passing
through that Point.
2.10 waterplane : A plane through a ship form, specifically a 2.10 ligne d’eau: Plan coupant Ia coque d’un navire, paral-
plane parallel to the designed load waterplane. Ielement a Ia ligne d’eau en Charge.
2.10.1 load waterplane : The waterplane corresponding to 2.10.1 ligne d’eau en Charge: Ligne d’eau correspondant a
the still water surface in the Summer load condition (as defined Ia surface de I’eau calme, dans Ia condition de chargement au
tirant d’eau d’ete (conformement aux reglements de franc-
by freeboard regulations) for which the ship is designed.
bord) pour laquelle Ie navire est calcule.
ISO 7462-1985 (E/F)
3 Grandeurs dimensionnelles (voir Ia figure)
Dimensional quantities (sec the figure)
largeur, B : Dimension du navire mesuree dans Ie sens
3.1
3.1 breadth, 6: A dimension expressing the width of a ship
transversal a I’horizontale.
in a transverse horizontal direction.
La largeur peut etre G hors membres» ou G hors tout )).
Breadth may be qualified as either moulded (2.6) or extreme
(2.2).
Sauf indication contraire, il s’agit generalement de Ia largeur
maximale hors membres qui peut elle-meme etre qualifiee,
When not otherwise defined, the maximum moulded breadth is
comme par exemple en 3.1.1 a 3.1.3.
implied, as for example in 3.1.1 to 3.1.3.
3.1.1 largeur maximale: Plus grande largeur hors membres
3.1.1 breadth, maximum : The greatest moulded breadth of
de Ia coque du navire.
the ship’s hull.
3.1.2 largeur au maltre couple : Largeur hors membres 8 ta
3.1.2 breadth, maximum section : The moulded breadth at
section de superficie maximale au tirant d’eau d’ete.
the section of maximum area to the designed Summer load
waterline.
3.1.3 largeur maximale immergee : Largeur maximale hors
3.1.3 breadth, maximum immersed: The maximum
membres de Ia Partie de Ia coque se trouvant sous I’eau.
moulded breadth of the underwater body.
NOTE - Le terme anglais G beam», utilise comme synonyme de
NOTE - The term “beam”, which has been used as a synonym for
(( breadth» (largeur), n’est pas tonforme a Ia terminologie de Ia pre-
breadth, does not conform to the terminology of this International
sente Norme internationale et n’est pas defini.
Standard and its use is deprecated.
3.2 depth, D: The principal vertical dimension of a ship’s 32 . creux, D: Principale dimension verticale d’une coque de
navire.
hull.
3.2.1 depth, moulded: Height above the baseline of the 3.2.1 creux sur quille: Hauteur, au-dessus de Ia ligne de
base, du Point Ie plus bas du dessous d’un pont donne a
lowest Point on the underside of a specified deck where it joins
I’endroit ou il tauche Ie borde de muraille.
the side of the ship.
3.3 deplacement: Terme a qualifier differemment selon
3.3 displacement : Displacement shall be qualified accord-
qu’il se refere a Ia forme de coque hors membres ou a Ia forme
ing to whether it refers to the moulded hull form or to the ex-
hors tout par rapport au borde de coque, et selon qu’il tient
treme form to the outside of the Shell plating and whether
campte des appendices positifs ou negatifs.
positive or negative appendages are included.
The differente between the moulded displacement and the ex- La differente entre Ie deplacement hors membres et Ie deplace-
ment hors tout est Ie dkpfacement du bord6 immergk
treme displacement is called the she// displacement.
3.3.1 displacement, mass: The mass of water displaced by 3.3.1 deplacement, masse: Masse de I’eau deplacee par Ie
navire flottant dans les conditions statiques, au tirant d’eau et a
a ship when floating statically at a specified draught and trim.
I’assiette specif ies.
The density of the water shall be specified or indicated by the
On doit specifier Ia masse volumique de I’eau, ou I’on doit faire
terms “fresh” implying a relative density of unity, or “salt” im-
figurer Ia mention G
...