FprEN 438-8

• Abstract:

  This document specifies performance requirements for design laminates intended for interior use with a design effect surface having a phenolic based core and a decorative surface not covered by EN 438 3 [1], EN 438 4 [2], EN 438 5 [3] and EN 438 6 [4].; This document is applicable to the following surface layer types:; — metal surfaces;; — wood veneer surfaces;; — pearlescent decor surfaces;; — lacquered surfaces.; NOTE For the test methods relevant to this document, see EN 438 2.

• Status: Not Published
• Publication Date: 31-Jan-2027
• ICS: 83.140.20 - Laminated sheets
• Technical Committee: CEN/TC 249 - Plastics
• Drafting Committee: CEN/TC 249/WG 4 - Decorative laminated sheets based on thermosetting resins
• Ref Project: oSIST prEN 438-8:2026 - High-pressure decorative laminates (HPL) - Sheets based on thermosetting resins (usually called laminates) - Part 8: Classification and specifications for design laminates

• Revises: EN 438-8:2018 - High-pressure decorative laminates (HPL) - Sheets based on thermosetting resins (usually called laminates) - Part 8: Classification and specifications for design laminates
• Effective Date: 21-May-2025

FprEN 438-8 is a draft European Standard from CEN for high-pressure decorative laminates (HPL) with design effect surfaces intended for interior use. It specifies how these laminates are classified and which performance requirements they must meet for pearlescent, metal, wood veneer and lacquered surfaces.

It is aimed at manufacturers, testers, specifiers and buyers who need a common basis for product designation, inspection and acceptance of design laminates.

What does FprEN 438-8 specify?

FprEN 438-8 specifies performance requirements for design laminates with a phenolic based core and a decorative surface that is not covered by EN 438-3, EN 438-4, EN 438-5 or EN 438-6. The document applies to interior-use products with metal surfaces, wood veneer surfaces, pearlescent decor surfaces and lacquered surfaces.

The structure is straightforward: Clause 1 gives the scope, Clause 2 lists the normative references, Clause 3 defines the terms and symbols, Clause 4 sets out the classification system, and Clause 5 gives the requirements. Annex A provides background information on reaction to fire.

What are the key requirements of FprEN 438-8?

FprEN 438-8 combines classification, inspection rules, dimensional tolerances and product-performance tests. In practice, it tells a supplier and purchaser how to identify a laminate type, how to inspect it, and which properties have to be demonstrated before the product is accepted.

Classification and product identification

Clause 4 sets out a four-letter classification system for high-pressure decorative design laminate. The system identifies the surface type, the application orientation or product family, the grade, and whether the laminate is standard, post-formable or flame-retardant.

This matters because product designation is not just a name. It is the way the product is ordered, specified and checked against the right set of requirements. Clause 4 also gives an example format using the document number and the classification letters.

Inspection and visual acceptance

Clause 5.2 requires inspection in accordance with EN 438-2, Clause 4, at a viewing distance between 750 mm and 1 500 mm. The clause then sets expectations for colour, pattern and surface finish for each laminate type.

This is important for production acceptance and receiving inspection. The standard accepts slight colour differences against the supplier reference sample in normal light and under D65 and A illuminants, but it also highlights practical points such as orientation-sensitive surfaces, the need to inspect without protective film, and the suitability of the reverse side for adhesive bonding. It also permits certain minor surface defects and edge conditions within the visual inspection basis agreed for a batch.

Dimensional tolerances

Clause 5.3 gives separate dimensional tolerance requirements for pearlescent, metal, wood veneer and lacquered laminates. Each product family has requirements for thin laminates and compact laminates, with flatness, edge straightness and, where relevant, squareness.

This matters because these laminates are used as finished visible surfaces, so thickness and flatness affect fabrication, fitting and final appearance. The clause also notes that cut-to-size panel tolerances are normally agreed between supplier and purchaser, which is important when the standard sheet format is being converted into finished parts.

Performance tests by laminate type

Clause 5.4 is the core performance section. It sets different test packages for pearlescent, metal, wood veneer and lacquered laminates, including resistance to wear, impact, scratching, dimensional stability at elevated temperature, staining, light fastness and resistance to water, water vapour, dry heat or wet heat depending on the laminate type.

For the user, this means the product is not judged by appearance alone. The laminate has to prove that it can withstand the service stresses expected for its declared grade, and the relevant test methods come from EN 438-2, EN ISO 178 and EN ISO 1183-1 where applicable.

Type P post-formable laminate

Clause 5.4.5 adds extra requirements for Type P high-pressure decorative design laminate. For post-formable pearlescent laminates and metal laminates up to the stated thickness limit, the document requires additional checks for formability and blister resistance.

This is the clause to look at when the laminate will be shaped after pressing. It matters for fabrication processes that involve bending or forming at elevated temperature, because the product has to remain usable after that extra processing step.

Reaction to fire

Clause 5.4.6 points to Annex A for reaction-to-fire information. Annex A explains that fire classification is normally driven by the country of use, and that for construction applications in Europe the relevant tests and classification route are based on EN 13823, EN ISO 11925-2 and EN 13501-1.

This is useful for project planning, but it is not a product fire-performance prescription inside this part. The annex makes clear that fire performance depends on laminate composition, decorative surface, thickness, substrate and adhesive, so fire suitability has to be checked for the actual end use.

What terms does FprEN 438-8 define?

• High-pressure decorative design laminate - a sheet made from decorative surface layer(s) and core layers bonded together by a high pressure process.
• Design laminate - the short form used for high-pressure decorative design laminate.
• HPL - the abbreviation for high-pressure decorative laminate used in the designation system.
• Surface layer - the decorative upper layer made from fibrous material, usually paper, impregnated with aminoplastic thermosetting resins.
• Core layer - the internal fibrous material, usually paper, impregnated with thermosetting resins, usually phenolic based resins.
• Pearlescent laminate - a design laminate with a pearlescent effect decorative paper as the surface layer.
• Metal laminate - a design laminate with a thin metal surface layer.
• Lacquered laminate - a design laminate whose surface layer consists of a lacquer or coating.
• t - the nominal thickness of the design laminate.

Who uses FprEN 438-8?

FprEN 438-8 is used by laminate manufacturers, fabricators, laboratory test houses, quality managers, purchasers and specifiers working with interior decorative surfaces. It gives them a common basis for product classification, inspection, dimensional control and performance testing.

In practice, manufacturers use it to design and declare product grades, laboratories use it to run the required EN 438-2 and related tests, buyers use it to compare offers and set acceptance criteria, and quality teams use it for incoming inspection and batch release. It is also relevant where fire-related project requirements have to be checked separately under national rules.

What changed in FprEN 438-8 from the previous edition?

FprEN 438-8 will supersede EN 438-8:2018. The foreword states these main technical changes:

• test methods have been updated where appropriate
• terms, definitions, symbols and abbreviations have been aligned with the other published parts of the EN 438 series
• the machined crosshead speed for flexural characteristics is aligned with EN 438-4:2016
• the terms and definitions have been updated
• the classification system now adds L for lacquered laminate
• Clause 5.3.4 has been added for dimensional tolerance requirements for lacquered laminates
• Clause 5.4.4 has been added for general requirements for lacquered laminates

Which standards are used with FprEN 438-8?

• EN 438-2:2016+A1:2018 - provides the test methods used throughout Clause 5 for inspection, dimensional checks and performance testing.
• EN ISO 178 - provides the flexural test method used for strength and modulus requirements.
• EN ISO 1183-1 - provides the density measurement method used for the density requirement.
• EN 438-1 - provides the general terms and definitions used in Clause 3.
• EN 438-3, EN 438-4, EN 438-5, EN 438-6 - define other laminate families that are outside the scope of this part.
• EN 438-7 and EN 438-9 - are neighboring parts in the EN 438 series listed in the foreword.
• EN 13823, EN ISO 11925-2, EN 13501-1 - are the fire-test and fire-classification standards referenced in Annex A for construction applications.
• EN ISO/CIE 11664-2 - provides the standard illuminants used for colour inspection.

What does the FprEN 438-8 document contain?

FprEN 438-8 contains a classification table, a full set of inspection criteria, dimensional tolerance tables and type-specific performance tables for the different laminate families. It also includes the additional requirements for Type P and an informative annex on reaction to fire.

The document is structured around practical manufacturing and acceptance tasks. It covers visual inspection, reverse-side suitability, thickness and flatness control, impact and scratch resistance, wear, staining, light fastness, heat and moisture resistance, flexural properties, density and, where relevant, fire-related guidance.

SLOVENSKI STANDARD
01-april-2026
Dekorativni visokotlačni laminati (HPL) - Plošče na osnovi duromernih smol
(laminati) - 8. del: Razvrstitev in specifikacije laminatov s posebnimi vzorci
High-pressure decorative laminates (HPL) - Sheets based on thermosetting resins
(usually called laminates) - Part 8: Classification and specifications for design laminates
Dekorative Hochdruck-Schichtpressstoffplatten (HPL) - Platten auf Basis härtbarer Harze
(Schichtpressstoffe) - Teil 8: Klassifizierung und Spezifikationen für Design-
Schichtpressstoffe
Stratifiés décoratifs haute pression (HPL) - Plaques à base de résines
thermodurcissables (communément appelées stratifiés) - Partie 8 : Classification et
spécifications relatives aux stratifiés à effets de surface spéciaux
Ta slovenski standard je istoveten z: prEN 438-8
ICS:
83.140.20 Laminatne plošče Laminated sheets
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 438-8
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2026
ICS 83.140.20 Will supersede EN 438-8:2018
English Version
High-pressure decorative laminates (HPL) - Sheets based
on thermosetting resins (usually called laminates) - Part 8:
Classification and specifications for design laminates
Stratifiés décoratifs haute pression (HPL) - Plaques à Dekorative Hochdruck-Schichtpressstoffplatten (HPL)
base de résines thermodurcissables (communément - Platten auf Basis härtbarer Harze (Schichtpressstoffe)
appelées stratifiés) - Partie 8 : Classification et - Teil 8: Klassifizierung und Spezifikationen für Design-
spécifications relatives aux stratifiés à effets de surface Schichtpressstoffe
spéciaux
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 249.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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 CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
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.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 438-8:2026 E
worldwide for CEN national Members.

prEN 438-8:2026 (E)
Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms, definitions and symbols . 4
3.1 General terms . 4
3.2 Types of high-pressure decorative design laminates . 5
3.3 Symbols . 6
4 Material types and classification system . 6
5 Requirements . 6
5.1 Compliance . 6
5.2 Inspection requirements . 6
5.2.1 General. 6
5.2.2 Colour, pattern and surface finish . 7
5.2.3 Reverse side . 7
5.2.4 Visual inspection . 7
5.3 Dimensional tolerance requirements . 8
5.3.1 Pearlescent laminates . 8
5.3.2 Metal laminates . 10
5.3.3 Wood veneer laminates . 12
5.3.4 Lacquered laminates . 14
5.4 Test requirements . 15
5.4.1 Pearlescent laminates . 15
5.4.2 Metal laminates . 17
5.4.3 Wood veneer laminates . 18
5.4.4 Lacquered laminates . 19
5.4.5 Additional requirements for type P high-pressure decorative design laminate . 21
5.4.6 Reaction to fire. 21
Annex A (informative) Information on reaction to fire. 22
Bibliography . 23

prEN 438-8:2026 (E)
European foreword
This document (prEN 438-8:2026) has been prepared by Technical Committee CEN/TC 249 “Plastics”,
the secretariat of which is held by SIS.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 438-8:2018.
prEN 438-8:2026 includes the following significant technical changes with respect to EN 438-8:2018:
— the test methods referenced have been updated as appropriate; the terms, definitions, symbols and
abbreviations are aligned with the other parts of the EN 438 series published; the machined
crosshead speed for the determination of the flexural characteristics, is the same of the one specified
in EN 438-4:2016.
— updating terms and definitions;
— adding “L – laquered laminate to high-pressure decorative design laminate classification system”;
— adding 5.3.4 “Dimensional tolerance requirements for lacquered laminates”;
— adding 5.4.4 “General requirements for lacquered laminates”.
The EN 438 series, under the general title High-pressure decorative laminates (HPL) — Sheets based on
thermosetting resins (usually called laminates), consists of the following parts:
— Part 1: Introduction and general information;
— Part 2: Determination of properties;
— Part 3: Classification and specifications for laminates less than 2 mm thick intended for bonding to
supporting substrates;
— Part 4: Classification and specifications for compact laminates of thickness 2 mm and greater;
— Part 5: Classification and specifications for flooring grade laminates less than 2 mm thick intended for
bonding to supporting substrates;
— Part 6: Classification and specifications for Exterior-grade compact laminates of thickness 2 mm and
greater;
— Part 7: Compact laminate and HPL composite panels for internal and external wall and ceiling finishes;
— Part 8: Classification and specifications for design laminates;
— Part 9: Classification and specifications for alternative core laminates.
prEN 438-8:2026 (E)
1 Scope
This document specifies performance requirements for design laminates intended for interior use with a
design effect surface having a phenolic based core and a decorative surface not covered by EN 438-3 [1],
EN 438-4 [2], EN 438-5 [3] and EN 438-6 [4].
This document is applicable to the following surface layer types:
— metal surfaces;
— wood veneer surfaces;
— pearlescent decor surfaces;
— lacquered surfaces.
NOTE For the test methods relevant to this document, see EN 438-2.
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.
EN 438-2:2016+A1:2018, High-pressure decorative laminates (HPL) — Sheets based on thermosetting
resins (usually called laminates) — Part 2: Determination of properties
EN ISO 178, Plastics — Determination of flexural properties (ISO 178)
EN ISO 1183-1, Plastics — Methods for determining the density of non-cellular plastics — Part 1:
Immersion method, liquid pycnometer method and titration method (ISO 1183-1)
3 Terms, definitions and symbols
For the purposes of this document, the terms and definitions given in EN 438-1 and the following 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/
3.1 General terms
3.1.1
high-pressure decorative design laminate
design laminate
HPL
sheet consisting of decorative design surface layer(s) and core layers bonded together by a high pressure
process
prEN 438-8:2026 (E)
3.1.2
surface layer
upper decorative layer consisting in one or more sheets of fibrous material (usually paper) impregnated
with aminoplastic thermosetting resins (usually melamine based resins)
Note 1 to entry: The surface layers appear on one or both side(s) of the laminate(s). They are not necessarily
treated with thermosetting resin. In case of one-sided laminates, the back of the sheet(s) can be made suitable for
adhesive bonding to a substrate.
3.1.3
core layer
fibrous materials (usually paper) impregnated with thermosetting resins (usually phenolic based resins)
3.2 Types of high-pressure decorative design laminates
3.2.1
pearlescent laminate
design laminate, the surface layer of which consists of a pearlescent effect decorative paper, which is
impregnated with aminoplastic thermosetting resins (usually melamine based resins)
Note 1 to entry: To achieve the optimum aesthetic effect from the pearlescent pigment a protective melamine layer
is not used.
Note 2 to entry: As a result some surface properties are reduced (e.g. scratch, wear), therefore it is recommended
that these products are used for vertical applications.
3.2.2
metal laminate
design laminate, the surface layer of which consists of a thin layer of metal
Note 1 to entry: Example: aluminium, steel or copper.
Note 2 to entry: It is often protected by a thin layer of lacquer or in the case of aluminium the surface can be
anodized. The surface performance and appearance of these metal laminates is equivalent to that of thin metal sheet.
Note 3 to entry: As some surface properties are lower than that of melamine (e.g. scratch and wear), it is
recommended that these products are used for vertical applications.
3.2.3
wood veneer laminate
design laminate, the surface layer of which consists of a wood veneer, which is covered by a protective
melamine layer
Note 1 to entry: The surface appearance of these wood veneer laminates is similar to wood.
Note 2 to entry: Wood veneer laminates are not normally available in postforming grade.
3.2.4
lacquered laminate
design laminate, the surface layer of which consists of a lacquer/coating
prEN 438-8:2026 (E)
3.3 Symbols
For the purposes of this document, the following symbols apply:
t nominal thickness of the design laminate
4 Material types and classification system
High-pressure decorative design laminate is defined using a four-letter classification system as shown in
Table 1.
Table 1 — High-pressure decorative design laminate classification system
First letter Second letter Third letter Fourth letter
A Pearlescent laminate H Horizontal G General purpose S Standard grade
(HPL < 2 mm)
M Metal laminate V Vertical D Heavy duty P Post-formable grade
(HPL < 2 mm) (horizontal)
W Wood veneer C Compact   F Flame-retardant
laminate grade
L Lacquered laminate
Type S – Standard grade high-pressure decorative design laminate.
Type P – Post-formable high-pressure decorative design laminate, similar to type S but can also be
formed at elevated temperature.
Type F – High-pressure decorative design laminate with improved fire retardance similar to type S or P
but also complying with special requirements of specified tests which can vary according to the
application (e.g. construction, marine, transport) and the country of use (see 5.4.5).
In addition to the abbreviation “HPL” and the number of this document (i.e. EN 438-8), materials shall be
specified by the alphabetical classification system.
EXAMPLE “Pearlescent, horizontal, general purpose, standard grade” is designated as HPL/EN 438-8 AHGS.
5 Requirements
5.1 Compliance
High-pressure decorative design laminate classified in Table 1 shall comply with all appropriate
requirements specified in 5.2, 5.3 and 5.4. This applies to both full-size sheets and cut-to-size panels.
5.2 Inspection requirements
5.2.1 General
Inspection shall be carried out in accordance with EN 438-2:2016+A1:2018, Clause 4, at a distance
between 750 mm and 1 500 mm.
prEN 438-8:2026 (E)
5.2.2 Colour, pattern and surface finish
5.2.2.1 Pearlescent
When inspected in daylight or D65 standard illuminant, as specified in EN ISO/CIE 11664-2, and also
illuminant A as specified in EN ISO/CIE 11664-2, a slight difference between the corresponding colour
reference sample held by the supplier and the specimen under test is acceptable.
As colour and surface finish are critical, it is recommended that sheets are checked for colour and surface-
finish compatibility without protective film before fabrication or installation.
Some of these products are directional in surface finish or colour and they shall be installed in the correct
orientation.
5.2.2.2 Metal
When inspected in daylight or D65 standard illuminant, as specified in EN ISO/CIE 11664-2, and also
illuminant A as specified in EN ISO/CIE 11664-2, a slight difference between the corresponding colour
reference sample held by the supplier and the specimen under test is acceptable.
As colour and surface finish are critical, it is recommended that sheets are checked for colour and surface-
finish compatibility without protective film before fabrication or installation.
Some of these products are directional in surface finish or colour and they shall be installed in the correct
orientation. Small indentations in the surface are unavoidable.
5.2.2.3 Wood veneer
Due to the fact that wood is a natural product, each veneer can be considered as unique. Slight colour and
structure differences are considered as normal. Singularities such as knots and resin inclusions are not
considered as defects, but as a part of the decor. There are differences in light fastness performances
depending on the wood species and the source of the wood.
5.2.2.4 Lacquered laminate
When inspected in daylight or D65 standard illuminant, as specified in EN ISO/CIE 11664-2, and also
illuminant A as specified in EN ISO/CIE 11664-2, a slight difference between the corresponding colour
reference sample held by the supplier and the specimen under test is acceptable.
As colour and surface finish are critical, it is recommended that sheets are checked for colour and surface-
finish compatibility without protective film before fabrication or installation.
Some of these products are directional in surface finish or colour and they shall be installed in the correct
orientation.
5.2.3 Reverse side
The reverse side of single-sided sheets shall be suitable for adhesive bonding (e.g. sanded). In the case of
sanded backs, slight chatter marks shall be permitted.
5.2.4 Visual inspection
5.2.4.1 General
The following inspection requirements are intended as a general guide, indicating the minimum
acceptable quality for laminates.
Cut-to-size panels and certain applications involving full-size sheets can call for special quality
requirements which can be negotiated between supplier and purchaser; in such cases the following
requirements can be used as a basis for agreement.
prEN 438-8:2026 (E)
Only a small percentage of sheets in a batch (the level to be agreed with the customer) should contain
defects of the minimum acceptable level.
5.2.4.2 Surface quality
The following surface defects are permissible:
a) Dirt, spots, dents and similar surface defects.
2 2
The admissible size of such defects is based on a maximum contamination area equivalent to 1,0 mm /m
of laminate and is proportional to the sheet size under inspection.
The total admissible area of contamination may be concentrated in one spot or dispersed over an
unlimited amount of smaller defects.
b) Fibres, hairs and scratches.
The admissible size of defects is based on a maximum contamination length equivalent to 10 mm/m of
laminate and is proportional to the sheet size under inspection.
The total admissible length of contamination may be concentrated in one defect or dispersed over an
unlimited amount of smaller defects.
5.2.4.3 Edge quality
Visual defects (e.g. moisture marks, lack of gloss, corner damage) can be present on all four edges of the
laminate, providing the defect-free length and width are at least the nominal size minus 20 mm.
For compact laminates edge chipping up to 3 mm on each side is permissible.
5.3 Dimensional tolerance requirements
5.3.1 Pearlescent laminates
Dimensions of pearlescent laminates shall be tested in accordance with the test methods and tolerances
specified in Table 2 and Table 3.
Table 2 — Dimensional tolerance requirements for thin pearlescent laminates
Test method
(EN 438-2:2016
Property Tolerance
+A1:2018,
clause no.)
0,5 mm ≤ t ≤ 1,0 mm ±0,10 mm
Thickness (t) 5
1,0 mm < t < 2,0 mm ±0,15 mm
a
Flatness 9 ±60 mm/m
+10
b
Length and width 6 (nominal size)
mm
b
Straightness of edges 7 ±1,5 mm/m
b
Squareness 8 ±1,5 mm/m
a
Provided that the pearlescent laminates are stored in the manner and conditions recommended by the
manufacturer they shall comply with the flatness requirements specified in Table 2 when measured in accordance
with EN 438-2:2016+A1:2018, Clause 9.
b
Tolerances for cut-to-size panels are normally agreed between supplier and purchaser.
prEN 438-8:2026 (E)
Table 3 — Dimensional tolerance requirements for compact pearlescent laminates
Test method
(EN 438-2:2016
Property Tolerance
+A1:2018,
clause no.)
2,0 mm ≤ t < 3,0 mm ± 0,20 mm
3,0 mm ≤ t < 5,0 mm ± 0,30 mm
5,0 mm ≤ t < 8,0 mm ± 0,40 mm
8,0 mm ≤ t < 12,0 mm ± 0,50 mm
12,0 mm ≤ t < 16,0 mm ± 0,60 mm
Thickness (t) 5
16,0 mm ≤ t < 20,0 mm ± 0,70 mm
20,0 mm ≤ t < 25,0 mm ± 0,80 mm
maximum variation to be
25,0 mm ≤ t agreed between supplier
and customer
2,0 mm ≤ t < 6,0 mm ±8,0 mm/
...