SIST EN ISO 1101:2006

SLOVENSKI STANDARD
SIST EN ISO 1101:2006
01-marec-2006
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Geometrical Product Specifications (GPS) - Geometrical tolerancing - Tolerances of
form, orientation, location and run-out (ISO 1101:2004)
Geometrische Produktspezifikation (GPS) - Geometrische Tolerierung - Tolerierung von
Form, Richtung, Ort und Lauf (ISO 1101:2004)
Spécification géométrique des produits (GPS) - Tolérancement géométrique -
Tolérancement de forme, orientation, position et battement (ISO 1101:2004)
Ta slovenski standard je istoveten z: EN ISO 1101:2005
ICS:
01.100.20 Konstrukcijske risbe Mechanical engineering
drawings
17.040.10 Tolerance in ujemi Limits and fits
SIST EN ISO 1101:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 1101:2006

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SIST EN ISO 1101:2006
EUROPEAN STANDARD
EN ISO 1101
NORME EUROPÉENNE
EUROPÄISCHE NORM
November 2005
ICS 01.100.20; 17.040.10

English Version
Geometrical Product Specifications (GPS) - Geometrical
tolerancing - Tolerances of form, orientation, location and run-
out (ISO 1101:2004)
Spécification géométrique des produits (GPS) - Geometrische Produktspezifikation (GPS) - Geometrische
Tolérancement géométrique - Tolérancement de forme, Tolerierung - Tolerierung von Form, Richtung, Ort und Lauf
orientation, position et battement (ISO 1101:2004) (ISO 1101:2004)
This European Standard was approved by CEN on 3 November 2005.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 1101:2005: E
worldwide for CEN national Members.

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SIST EN ISO 1101:2006
EN ISO 1101:2005 (E)






Foreword



The text of ISO 1101:2004 has been prepared by Technical Committee ISO/TC 213
"Dimensional and geometrical product specifications and verification” of the International
Organization for Standardization (ISO) and has been taken over as EN ISO 1101:2005 by
Technical Committee CEN/TC 290 "Dimensional and geometrical product specification and
verification", the secretariat of which is held by AFNOR.

This European Standard shall be given the status of a national standard, either by publication of
an identical text or by endorsement, at the latest by May 2006, and conflicting national standards
shall be withdrawn at the latest by May 2006.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.


Endorsement notice

The text of ISO 1101:2004 has been approved by CEN as EN ISO 1101:2005 without any
modifications.

2

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SIST EN ISO 1101:2006
INTERNATIONAL ISO
STANDARD 1101
Second edition
2004-12-15
Geometrical Product Specifications
(GPS) — Geometrical tolerancing —
Tolerances of form, orientation, location
and run-out
Spécification géométrique des produits (GPS) — Tolérancement
géométrique — Tolérancement de forme, orientation, position et battement

Reference number
ISO 1101:2004(E)
© ISO 2004

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SIST EN ISO 1101:2006
ISO 1101:2004(E)
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©
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
Contents Page
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Basic concepts . 3
5 Symbols . 4
6 Tolerance frame . 6
7 Toleranced features . 7
8 Tolerance zones . 8
9 Datums . 11
10 Supplementary indications . 13
11 Theoretically exact dimensions (TED) . 13
12 Restrictive specifications . 14
13 Projected tolerance zone . 15
14 Maximum material requirement . 15
15 Least material requirement . 15
16 Free state condition . 16
17 Interrelationship of geometrical tolerances . 16
18 Definitions of geometrical tolerances . 16
Annexes
A Former practices . 46
B Assessment of geometrical deviations. 49
C Relation to the GPS matrix model. 53
Bibliography. 54
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SIST EN ISO 1101:2006
ISO 1101:2004(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards adopted
by the technical committees are circulated to the member bodies for voting. Publication as an International Standard
requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 1101 was prepared by Technical Committee ISO/TC 213, Dimensional and geometrical product specifications
and verification.
This second edition cancels and replaces the first edition (ISO 1101:1983), which has been technically revised.
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
Introduction
This International Standard is a geometrical product specification (GPS) standard and is to be regarded as a general
GPS standard (see ISO/TR 14638). It influences chain links 1 and 2 of the chain of standards on form, orientation,
location and run out, and chain link 1 of the chain of standards on datums.
For more detailed information on the relation of this International Standard to the GPS matrix model, see Annex C.
This International Standard represents the initial basis and describes the required fundamentals for geometrical
tolerancing. Nevertheless, it is advisable to consult the separate standards referenced in Clause 2 and in Table 2 for
more detailed information.
For the presentation of lettering (proportions and dimensions), see ISO 3098-2.
In the interest of uniformity, all figures in this International Standard have been drawn in first angle projection with
dimensions and tolerances in millimetres. It should be understood that third angle projection and other units of
measurement could have been used equally well without prejudice to the principles established.
The figures in this International Standard illustrate the text and are not intended to reflect an actual application.
Consequently, the figures are not fully dimensioned and toleranced, showing only the relevant general principles.
For a definitive presentation (proportions and dimensions) of the symbolization for geometrical tolerancing, see
ISO 7083.
AnnexA of this International Standard has been provided for information only. It presents previous drawing
indications that have been omitted here and are no longer used.
It needs to be noted that the former use of the term “circularity” has been changed to the term “roundness” for
reasons of consistency with other standards.
Definitions of features are taken from ISO 14660-1 and ISO 14660-2, which provide new terms different from those
used in previous edition of this International Standard. The former terms are indicated in the text following the new
terms, between parentheses.
For the purposes of this International Standard, the terms “axis” and “median plane” are used for derived features of
perfect form, and the terms “median line” and “median surface” for derived features of imperfect form. Furthermore,
the following line types have been used in the explanatory illustrations, i.e. those representing non-technical
drawings for which the rules of ISO 128 (all parts) apply.
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
Line type
Feature level Feature type Details
Visible Behind plane/surface
point
integral feature line/axis wide continuous narrow dashed
surface/plane
Nominal feature (ideal
feature)
point
narrow long dashed
derived feature line/axis narrow dashed dotted
dotted
face/plane
wide freehand
Real feature integral feature surface narrow freehand dashed
continuous
point
integral surface line wide short dashed narrow short dashed
surface
Extracted feature
point
derived feature line wide dotted narrow dotted
face
point
wide doubled-dashed narrow double-dashed
integral feature straight line
double-dotted double-dotted
ideal feature
point
narrow long dashed wide dashed double-
Associated feature derived feature straight line
double-dotted dotted
plane
point
wide long dashed narrow long dashed
datum line
double-short dashed double-short dashed
surface/plane
Tolerance zone limits, line
continuous narrow narrow dashed
tolerances planes surface
Section, illustration
line narrow long dashed narrow dashed short
plane, drawing plane,
surface short dashed dashed
aid plane
Extension, dimension,
leader and reference line continuous narrow narrow dashed
lines
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SIST EN ISO 1101:2006
INTERNATIONAL STANDARD ISO 1101:2004(E)
Geometrical Product Specifications (GPS) — Geometrical
tolerancing — Tolerances of form, orientation, location and run-out
IMPORTANT — The illustrations included in this International Standard are intended to illustrate the text
and/or to provide examples of the related technical drawing specification; these illustrations are not fully
dimensioned and toleranced, showing only the relevant general principles.
As a consequence, the illustrations are not a representation of a complete workpiece, and are not of a
quality that is required for use in industry (in terms of full conformity with the standards prepared by
ISO/TC 10 and ISO/TC 213), and as such are not suitable for projection for teaching purposes.
This and future editions of ISO1101 will be revised to include improved illustrations whenever new
amendments for ISO 1101 have reached the stage of publication.
1 Scope
This International Standard contains basic information and gives requirements for the geometrical tolerancing of
workpieces.
It represents the initial basis and defines the fundamentals for geometrical tolerancing.
NOTE Other International Standards referenced in Clause 2 and in Table 2 provide more detailed information on geometrical
tolerancing.
2 Normative references
The following referenced documents are indispensable for the application 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 128-24:1999, Technical drawings — General principles of presentation — Part24: Lines on mechanical
engineering drawings
ISO 1660:1987, Technical drawings — Dimensioning and tolerancing of profiles
1)
ISO 2692:— , Geometrical Product Specification (GPS) — Geometrical tolerancing — Maximum material
requirement (MMR) and least material requirement (LMR)
ISO 5458:1998, Geometrical Product Specifications (GPS) — Geometrical tolerancing — Positional tolerancing
ISO 5459:1981, Technical drawings — Geometrical tolerancing — Datums and datum-systems for geometrical
tolerances
1) To be published. (Revision of ISO 2692:1988)
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
ISO 8015:1985, Technical drawings — Fundamental tolerancing principle
ISO 10578:1992, Technical drawings — Tolerancing of orientation and location — Projected tolerance zone
ISO 10579:1993, Technical drawings — Dimensioning and tolerancing — Non-rigid parts
ISO/TS 12180-1:2003, Geometrical Product Specifications (GPS) — Cylindricity — Part1: Vocabulary and
parameters of cylindrical form
ISO/TS 12180-2:2003, Geometrical Product Specifications (GPS) — Cylindricity — Part 2: Specification operators
ISO/TS 12181-1:2003, Geometrical Product Specifications (GPS) — Roundness — Part1: Vocabulary and
parameters of roundness
ISO/TS 12181-2:2003, Geometrical Product Specifications (GPS) — Roundness — Part 2: Specification operators
ISO/TS 12780-1:2003, Geometrical Product Specifications (GPS) — Straightness — Part1: Vocabulary and
parameters of straightness
ISO/TS 12780-2:2003, Geometrical Product Specifications (GPS) — Straightness — Part 2: Specification operators
ISO/TS 12781-1:2003, Geometrical Product Specifications (GPS) — Flatness — Part 1: Vocabulary and parameters
of flatness
ISO/TS 12781-2:2003, Geometrical Product Specifications (GPS) — Flatness — Part 2: Specification operators
ISO 14660-1:1999, Geometrical Product Specifications (GPS) — Geometrical features — Part 1: General terms and
definitions
ISO 14660-2:1999, Geometrical Product Specifications (GPS) — Geometrical features — Part 2: Extracted median
line of a cylinder and a cone, extracted median surface, local size of an extracted feature
ISO/TS 17450-2:2002, Geometrical product specifications (GPS) — General concepts — Part 2: Basic tenets,
specifications, operators and uncertainties
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14660-1 and ISO 14660-2 and the
following apply.
3.1
tolerance zone
space limited by one or several geometrically perfect lines or surfaces, and characterized by a linear dimension,
called a tolerance
NOTE See also 4.4.
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
4 Basic concepts
4.1 Geometrical tolerances shall be specified in accordance with functional requirements. Manufacturing and
inspection requirements can also influence geometrical tolerancing.
NOTE Indicating geometrical tolerances on a drawing does not necessarily imply the use of any particular method of production,
measurement or gauging.
4.2 A geometrical tolerance applied to a feature defines the tolerance zone within which that feature shall be
contained.
4.3 A feature is a specific portion of the workpiece, such as a point, a line or a surface; these features can be
integral features (e.g. the external surface of a cylinder) or derived (e.g. a median line or median surface). See
ISO 14660-1.
4.4 According to the characteristic to be toleranced and the manner in which it is dimensioned, the tolerance zone
is one of the following:
— the space within a circle;
— the space between two concentric circles;
— the space between two equidistant lines or two parallel straight lines;
— the space within a cylinder;
— the space between two coaxial cylinders
— the space between two equidistant surfaces or two parallel planes;
— the space within a sphere.
4.5 Unless a more restrictive indication is required, for example by an explanatory note (see Figure 8), the
toleranced feature may be of any form or orientation within this tolerance zone.
4.6 The tolerance applies to the whole extent of the considered feature unless otherwise specified as in Clauses 12
and 13.
4.7 Geometrical tolerances which are assigned to features related to a datum do not limit the form deviations of the
datum feature itself. It may be necessary to specify tolerances of form for the datum feature(s).
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
5 Symbols
See Tables 1 and 2.
Table 1 — Symbols for geometrical characteristics
Tolerances Characteristics Symbol Datum needed Subclause
Straightness no 18.1
Flatness no 18.2
Roundness no 18.3
Form
Cylindricity no 18.4
Profile any line no 18.5
Profile any surface no 18.7
Parallelism yes 18.9
Perpendicularity yes 18.10
Orientation
Angularity yes 18.11
Profile any line yes 18.6
Profile any surface yes 18.8
Position yes or no 18.12
Concentricity (for centre points) yes 18.13
Coaxiality (for axes) yes 18.13
Location
Symmetry yes 18.14
Profile any line yes 18.6
Profile any surface yes 18.8
Circular run-out yes 18.15
Run-out
Total run-out yes 18.16
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
Table 2 — Additional symbols
Description Symbol Reference
Toleranced feature indication Clause 7
Datum feature indication Clause 9 and ISO 5459
Datum target indication ISO 5459
Theoretically exact dimension Clause 11
Projected tolerance zone Clause 13 and ISO 10578
Maximum material requirement Clause 14 and ISO 2692
Least material requirement Clause 15 and ISO 2692
Free state condition (non-rigid parts) Clause 16 and ISO 10579
All around (profile) Subclause 10.1
Envelope requirement ISO 8015
Common zone Subclause 8.5
Minor diameter Subclause 10.2
Major diameter Subclause 10.2
Pitch diameter Subclause 10.2
Line element Subclause 18.9.4
Not convex Subclause 6.3
Any cross-section Subclause 18.13.1
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
6 Tolerance frame
6.1 The requirements are shown in a rectangular frame which is divided into two or more compartments. These
compartments contain, from left to right, in the following order (see examples of Figures 1, 2, 3, 4 and 5):
— the symbol for the geometrical characteristic;
— the tolerance value in the unit used for linear dimensions. This value is preceded by the symbol “” if the
tolerance zone is circular or cylindrical; or by “” if the tolerance zone is spherical;
— if applicable, the letter or letters identifying the datum or common datum or datum system (see examples of
Figures 2, 3, 4 and 5).
Figure 1 Figure 2 Figure 3 Figure 4 Figure 5
6.2 When a tolerance applies to more than one feature this shall be indicated above the tolerance frame by the
number of features followed by the symbol “”× (see examples of Figures 6 and 7).
Figure 6 Figure 7
6.3 If required, indications qualifying the form of the feature within the tolerance zone shall be written near the
tolerance frame (see example of Figure 8).
NOTE See also Table 2.
Figure 8
6.4 If it is necessary to specify more than one geometrical characteristic for a feature, the requirements may be
given in tolerance frames one under the other for convenience (see example of Figure 9).
Figure 9
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
7 Toleranced features
The tolerance frame shall be connected to the toleranced feature by a leader line starting from either side of the
frame and terminating with an arrowhead in one of the following ways:
— on the outline of the feature or an extension of the outline (but clearly separated from the dimension line) when
the tolerance refers to the line or surface itself (see examples of Figures 10 and 11); the arrowhead may be
placed on a reference line using a leader line to point to the surface (see example of Figure 12);
Figure 10 Figure 11
Figure 12
— as an extension of the dimension line when the tolerance refers to the median line or median surface or a point
defined by the feature so dimensioned (see examples of Figures 13, 14 and 15).
Figure 13 Figure 14 Figure 15
If needed, an indication specifying the form of the feature (line instead of a surface) shall be written near the
tolerance frame (see Figures 88 and 89).
NOTE When the toleranced feature is a line, a further indication might be needed to control the orientation, see Figure 89.
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
8 Tolerance zones
8.1 The width of the tolerance zone applies normal to the specified geometry (see examples of Figures 16 and 17)
unless otherwise indicated (see examples of Figures 18 and 19).
NOTE The orientation alone of the leader line does not influence the definition of the tolerance.
a
Datum A.
Drawning indication Interpretation
Figure 16 Figure 17
a
Datum A.
Drawning indication Interpretation
Figure 18 Figure 19
◦
The angle α shown in Figure 18 shall be indicated, even if it is equal to 90 .
In the case of roundness, the width of the tolerance zone always applies in a plane perpendicular to the nominal axis.
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
8.2 In the case of a centre point or median line or median surface toleranced in one direction:
— the orientation of the width of a positional tolerance zone is based on the pattern of the theoretically exact
◦ ◦
dimensions (TED) and is at 0 or 90 as indicated by the direction of the arrowhead of the leader line unless
otherwise indicated (see example of Figure 20);
Figure 20
◦ ◦
— the orientation of the width of an orientation tolerance zone is at 0 or 90 relative to the datum as indicated by
the direction of the arrowhead of the leader line unless otherwise indicated (see examples of Figures 21 and 22);
— when two tolerances are stated, they shall be perpendicular to each other unless otherwise specified (see
examples of Figures 21 and 22).
Drawning indication
Figure 21
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
a
Datum A
b
Datum B
Interpretation
Figure 22
8.3 The tolerance zone is cylindrical (see examples of Figures 23 and 24) or circular if the tolerance value is
preceded by the symbol “” or spherical if it is preceded by the symbol “”.
a
Datum A.
Drawning indication Interpretation
Figure 23 Figure 24
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
8.4 Individual tolerance zones of the same value applied to several separate features may be specified (see
example of Figure 25).
Figure 25
8.5 Where a single tolerance zone is applied to several separate features, the requirement shall be indicated by the
symbol “CZ” for common zone following the tolerance in the tolerance frame (see example of Figure 26).
Figure 26
9Datums
9.1 Datums shall be indicated as given in the examples in 9.2 to 9.5. For additional information see ISO 5459.
NOTE At the next revision of this International Standard, this clause will be moved to ISO 5459.
9.2 A datum related to a toleranced feature shall be designated by a datum letter. A capital letter shall be enclosed
in a datum frame and connected to a filled or open datum triangle to identify the datum (see examples of Figures 27
and 28); the same letter which defines the datum shall also be indicated in the tolerance frame. There is no difference
in the meaning between a filled and an open datum triangle.
Figure 27 Figure 28
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SIST EN ISO 1101:2006
ISO 1101:2004(E)
9.3 The datum triangle with the datum letter shall be placed:
— on the outline of the feature or an extension of the outline (but clearly separated from the dimension line), when
the datum is the line or surface shown (see example of Figure 29); the datum triangle may be placed on a
reference line using a leader line to point to the surface (see example of Figure 30);
Figure 29 Figure 30
— as an extension of the dimension line when the datum is the axis or median plane or a point defined by the
feature so dimensioned (see examples of Figures 31 to 33). If there is insufficient space for two arrowheads, one
of them may be replaced by the
...