ISO 20537:2025
(Main)Footwear — Identification of defects during visual inspection — Vocabulary
Footwear — Identification of defects during visual inspection — Vocabulary
This document defines the most common terms related to defects that occur in the manufacture, storage and usage of footwear and that can be determined during visual inspection of the end product. NOTE The photos are given as examples and do not represent all possible instances.
Chaussures — Identification des défauts lors d'un contrôle visuel — Vocabulaire
General Information
Standards Content (Sample)
International
Standard
ISO 20537
First edition
Footwear — Identification of
2025-01
defects during visual inspection —
Vocabulary
Reference number
© ISO 2025
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
3.1 General defects .1
3.2 Defects in materials aspects .4
3.3 Defects in components .5
3.3.1 Defects in upper .5
3.3.2 Defects in counter and toe puff .8
3.3.3 Defects in lining and insock.10
3.3.4 Defects in welt and foxing .11
3.3.5 Defects in heel . . 12
3.3.6 Defects in outsole.14
3.3.7 Defects in other components . 15
3.4 Manufacturing defects .17
3.4.1 Defects in assembly .17
3.4.2 Gluing defects .19
3.4.3 Sewing defects . 20
3.4.4 Defects in other process . 23
3.5 Defects within pairs .24
3.6 Defects in markings . 28
Bibliography .31
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 216, Footwear, in collaboration with the
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with the Agreement on technical cooperation between ISO and CEN (Vienna Agreement).
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iv
Introduction
Visual inspection is important for manufacturers, suppliers, inspection organizations and costumers as one
of the quality indicators of footwear products. This document is not only intended as a basis for assessing
footwear appearance defects but also as a reference material and training material for the footwear industry.
The presence of one of these defects in footwear does not automatically imply that the footwear is
substandard. Suppliers and purchasers can still reach an agreement on the scope and level of acceptance for
defects in the goods, based on the intended use of the footwear.
Due to the development of material and technology in the footwear industry, as well as insufficient
photographic resources, it is impossible to define all terms for identification of defects during visual
inspection of footwear. The list of terms given in this document is not exhaustive.
v
International Standard ISO 20537:2025(en)
Footwear — Identification of defects during visual inspection
— Vocabulary
1 Scope
This document defines the most common terms related to defects that occur in the manufacture, storage
and usage of footwear and that can be determined during visual inspection of the end product.
NOTE The photos are given as examples and do not represent all possible instances.
2 Normative references
There are no normative references in this document.
3 Terms and definitions
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/
3.1 General defects
Term and definition Examples
3.1.1
colour variation
obvious difference in colour that can be seen in the same
area within a pair, or in one component part or in the
adjacent areas of one item of footwear
Note 1 to entry: Intentional designs are not included.
3.1.2
damaged shoe
footwear that has changed in appearance due to careless
operation that adversely affects its performance
Term and definition Examples
3.1.3
inconformity with the design
situation when a product does not conform to the reference
sample or drawing which both parties have agreed upon
drawing product
3.1.4
mildewing
infecting process by microorganisms on material at any
part of the footwear
3.1.5
non-compliant box
shoe box that does not conform with the footwear inside
Term and definition Examples
3.1.6
poor printing
printing on footwear that is incomplete or unclear
3.1.7
soiled shoe
shoe with dirt or adhesive mark on the upper, lining or sides
of the sole due to careless handling or cleaning
3.1.8
spue
white frost-like layer that appears on the surface of footwear
3.1.9
weave fault
defect that reduces the expected performance of the fabric
Note 1 to entry: Related defects are described in ISO 8498
and ISO 8499.
3.2 Defects in materials aspects
Term and definition Examples
3.2.1
air hole
small hole which develops in the colloid structure of materials
3.2.2
colour migration
discolouration caused by movement of colour from one
material to another
3.2.3
crazing
cracks in the coating of upper materials
3.2.4
discolouration
staining or fading of the original material colour, either in
discrete areas or across the whole product
3.2.5
impurity
small particles that do not belong to the original formulation
and show on the material
Term and definition Examples
3.2.6
pit
small hole in the surface of footwear
3.2.7
shade variation
differences within materials that cause a difference in the
shade of the finished footwear
3.2.8
sulfur blooming
yellow or white layer that appears on the surface of rubber
materials
3.3 Defects in components
3.3.1 Defects in upper
Term and definition Examples
3.3.1.1
broken folding
folding of upper over the edge that has broken during the
making or wearing process
Term and definition Examples
3.3.1.2
crease on the upper
wrinkles on the upper area of footwear due to poor sewing
process
3.3.1.3
delamination of upper
separation of upper into its constituent layers, either in
whole or in part
Term and definition Examples
3.3.1.4
exposed lasting margin
scoured lasting margin of the upper that is exposed above
the lasting edge
3.3.1.5
grain crack
grain surface of leather in upper that is split or cracked, or
on which a rupture pattern has developed
3.3.1.6
wrinkled leather
loose grain
grain whose attachment to corium has been eroded, giving
rise to pronounced wrinkles when leather is bent, grain
inside
[SOURCE: ISO 15115:2019, 3.55, modified — the preferred
term “wrinkled leather” has been added.]
3.3.2 Defects in counter and toe puff
Term and definition Examples
3.3.2.1
collapsed counter
counter area of footwear that has collapsed due to the
stiffener either becoming detached or weakened
3.3.2.2
collapsed toe puff
toe that is distorted and buckled because the reinforcement
has collapsed within, leaving creases and/or dents
Term and definition Examples
3.3.2.3
uneven counter
counter edge that has become creased
Note 1 to entry: Uneven counter can be due to excessive force
used during the lasting process or a poor sewing process.
3.3.2.4
uneven toe puff
toe puff of the shoe that has become cre
...
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