Aerospace series - Acceptance parameters of aesthetical variations for all visible equipment installed in aircraft cabins under all contractual variations

This document defines the inspection rules and the cosmetic acceptance criteria for surfaces of aircraft cabin equipment. Surfaces will be considered under the aspects of technical feasibility of the industrial design.
This document outlines the framework between airlines, supplier and OEMs with regard to cosmetic issues.
This document aims to:
a)   provide the supplier or manufacturer with quality criteria, which need to be met during the production, testing- and quality-inspection-process.
b)   guide airline-, OEM- and supplier-quality assurance with a description of cosmetic standards for following inspections:   -   supplier internal QA inspection;
-   first article inspection;
-   source inspection;
-   incoming inspection;
-   final assembly line, cabin inspection;
-   customer presentation.

Luft- und Raumfahrt - Abnahmeparameter von ästhetischen Qualitätsabweichungen für alle sichtbaren Flugzeug-Kabinenbauteile in allen vertraglichen Varianten

Série aérospatiale - Acceptation des variations esthétiques de l'aspect des éléments visibles de cabine d'avion sous toute forme contractuelle

Aeronavtika - Prevzemna merila za estetske različice vseh vidnih naprav, vgrajenih v letalske potniške kabine po vseh pogodbenih različicah (vključno s popravkom AC)

Ta dokument določa pravila pregledov in prevzemna merila estetske sprejemljivosti vseh površin letalske potniške kabine. Površine bodo obravnavane z vidika tehnične izvedljivosti industrijske zasnove.
Ta dokument določa okvir za letalske družbe, dobavitelja in proizvajalce originalne opreme glede kozmetičnih elementov.
Cilj tega dokumenta je opredeliti:
a) merila kakovosti za dobavitelja ali proizvajalca, ki morajo biti izpolnjena med proizvodnjo, preskušanjem in izvajanjem postopkov preverjanja kakovosti;
b) smernice za letalske družbe, proizvajalca originalne opreme in dobavitelja pri zagotavljanju kakovosti z opisom kozmetičnih standardov pri naslednjih pregledih:   
– interno preverjanje kakovosti dobavitelja;
– prvi pregled artiklov;
– preverjanje izvora;
– vhodni pregled;
– končni pregled serijsko izdelane kabine;
– predstavitev stranki.

General Information

Status
Published
Publication Date
07-May-2019
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
18-Apr-2019
Due Date
23-Jun-2019
Completion Date
08-May-2019

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SLOVENSKI STANDARD
SIST EN 4726:2019+AC:2019
01-junij-2019
Nadomešča:
SIST EN 4726:2019
Aeronavtika - Prevzemna merila za estetske različice vseh vidnih naprav, vgrajenih
v letalske potniške kabine po vseh pogodbenih različicah (vključno s popravkom
AC)
Aerospace series - Acceptance parameters of aesthetical variations for all visible
equipment installed in aircraft cabins under all contractual variations
Luft- und Raumfahrt - Abnahmeparameter von ästhetischen Qualitätsabweichungen für
alle sichtbaren Flugzeug-Kabinenbauteile in allen vertraglichen Varianten
Série aérospatiale - Acceptation des variations esthétiques de l'aspect des éléments
visibles de cabine d'avion sous toute forme contractuelle
Ta slovenski standard je istoveten z: EN 4726:2018+AC:2019
ICS:
49.095 Oprema za potnike in Passenger and cabin
oprema kabin equipment
SIST EN 4726:2019+AC:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 4726:2019+AC:2019

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SIST EN 4726:2019+AC:2019


EN 4726:2018+AC
EUROPEAN STANDARD

NORME EUROPÉENNE

April 2019
EUROPÄISCHE NORM
ICS 49.095 Supersedes EN 4726:2018
English Version

Aerospace series - Acceptance parameters of aesthetical
variations for all visible equipment installed in aircraft
cabins under all contractual variations
Série aérospatiale - Acceptation des variations Luft- und Raumfahrt - Abnahmeparameter von
esthétiques de l'aspect des éléments visibles de cabine ästhetischen Qualitätsabweichungen für alle
d'avion sous toute forme contractuelle sichtbaren Flugzeug-Kabinenbauteile in allen
vertraglichen Varianten
This European Standard was approved by CEN on 13 May 2018 and includes the Corrigendum issued by CEN on 10 April 2019.

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 CEN-CENELEC Management Centre 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 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATIO N

EUROPÄISCHES KOMITEE FÜR NORMUN G

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4726:2018+AC:2019 E
worldwide for CEN national Members.

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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
Contents
Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms, definitions and abbreviations . 4
4 Definitions of cosmetic defects, inspection zones and criteria . 6
5 Unacceptable characteristics . 39
6 Evaluation tables and defect size assessment . 62
7 Inspection template to ascertain defect sizes . 64
(informative) Standard evolution form . 66

2

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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
European foreword
This document (EN 4726:2018+AC:2019) has been prepared by the Aerospace and Defence Industries
Association of Europe - Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
This document shall be given the status of a national standard, either by publication of an identical text
or by endorsement, at the latest by October 2019, and conflicting national standards shall be withdrawn
at the latest by October 2019.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document includes Corrigendum 1 issued by CEN on 10 April 2019.
This document supersedes ˜EN 4726:2018™.
The start and finish of text introduced or altered by corrigendum is indicated in the text by tags
˜ ™.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
3

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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
1 Scope
This document defines the inspection rules and the cosmetic acceptance criteria for surfaces of aircraft
cabin equipment. Surfaces will be considered under the aspects of technical feasibility of the industrial
design.
This document outlines the framework between airlines, supplier and OEMs with regard to cosmetic
issues.
This document aims to:
a) provide the supplier or manufacturer with quality criteria, which need to be met during the
production, testing- and quality-inspection-process.
b) guide airline-, OEM- and supplier-quality assurance with a description of cosmetic standards for
following inspections:
— supplier internal QA inspection;
— first article inspection;
— source inspection;
— incoming inspection;
— final assembly line, cabin inspection;
— customer presentation.
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 12464-1, Light and lighting - Lighting of work places — Part 1: Indoor work places
EN ISO 2813, Paints and varnishes — Determination of gloss value at 20°, 60° and 85°
3 Terms, definitions and abbreviations
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
4

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EN 4726:2018+AC:2019 (E)
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
3D three Dimensional
BFE Buyer Furnished Equipment (from OEM perspective)
CAS Cabin Attendant Seat
CDR Critical Design Review
CIE international commission on illumination
DPI Dots Per Inch
DSM Decorative Sheet Material
e.g. for example
etc. and so on
FAI First Article Inspection
FAL Final Assembly Line (OEM)
FFF Fit, Form and Function
HTPT Hydro Transfer Printing Technology
i.e. that is to say
ICS Industrial design Colour Specification (OEM)
incl. including
LED Light Emitting Diode
LHS Left Hand Side
NTF Non-Textile Floor
OEM Original Equipment Manufacturer
PTS Purchaser Technical Specification
PVF polyvinyl fluoride film
RFC Request For Change
RHS Right Hand Side
QC Quality Control
SCN Specific Change Note
SFE Seller Furnished Equipment (from OEM perspective)
SSBFE Seller Supplied BFE
SU Standard Unit
UV UltraViolet
5

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EN 4726:2018+AC:2019 (E)
4 Definitions of cosmetic defects, inspection zones and criteria
4.1 Simplified definition of a cosmetic defect
Cosmetic defects are deviations from the standard or customized specifications/definitions. They are
distinct from a certain distance without additional illumination and/or mirror and according to the
definitions thereof within this European standard. Cosmetic defects do not affect fit-form-function as a
rule, however in certain extreme cases this might actually be the case e.g. if paint build up impedes
fitting. The defects listed encompass any process relevant material.
Seller furnished equipment (SFE) or similar status: The supplier is not allowed to approach the airline
concerning cosmetic issues or definition changes.
Buyer Furnished Equipment (BFE)/Seller Supplied BFE (SSBFE) or similar status: Pickups or points of
contention raised by OEM which are disputed between both parties (OEM and supplier or
manufacturer) will be submitted to the customer to make the definitive and binding decision for all
parties. Any decision has to be documented by the supplier or manufacturer and accompany each
individual unit in a conspicuous legible way without causing damage to the part/parts in question. All
parties will adhere to the customer decision until as such times another supersedes it.
For SFE, SSBFE and BFE all samples have to be supplied by the supplier and/or the customer to the
OEM in order to validate the inspection.
4.2 Zonal type definition for installed parts
4.2.1 Zone A
All primary viewed surfaces by a potential passenger or crew either walking through the aircraft or in
any normal seating position or passenger/crew used furniture, e.g. table top/backs. Any surface which
is directly seen, through either expected operation or expected viewing movement, see Figure 1.



a) Passegner and crew b) Passenger and c) Passenger and crew member
member seating, top view crew member walking
seating, side view
NOTE The viewing cone would move according to the head movements up/down and left/right.
Figure 1 — Passenger’s viewing cone when seating in any position or walking through the cabin
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EN 4726:2018+AC:2019 (E)
4.2.2 Zone B
Secondary perceived surfaces - surfaces requiring extreme movement of the viewing angle to be
perceived, i.e. the viewer has to abnormally bend to be able to see it. Areas which may be perceived by
passengers or crew through normal operation e.g. stowages inside and stowage doors inside. Standard
stowage interiors are appraised from the stowage door threshold, not by climbing or poking the head
inside.
Purposely designed “walk in” monuments shall be entered and appraised in the standard method from
within i.e. interior walls are A zone etc.
4.2.3 Zone C
Surfaces that require - first “opening up”, e.g. folding, moving or removal of primary or secondarily
viewed areas, In order to view the area in question e.g. inside a lavatory mirror cabinet. Can only be
viewed using equipment. Areas expected to be perceived by support staff and not passengers. Areas not
visible after installation and that have no defined aesthetical surface treatment are still within the
parameters of zone C; however still maintaining other requirements e.g. closed edges, fit, form and
function etc. Sizes/dimensions of areas/surfaces eligible shall be demonstrated in the technical
documentation and require the OEM acceptance.
4.3 Classification of surfaces to be inspected
The surfaces to be inspected are classified into three zones (A, B, C).
Customers and suppliers shall document at initial technical coordination meeting or functionally similar
meeting latest at Critical Design Review (CDR) or functionally similar meeting areas that may be
exceptions after installation in the cabin of the aircraft, all other surfaces according to the below zonal
prerequisites unless otherwise agreed.
For BFE additionally (or similar status):
The customer is required to clearly document and inform the OEM and supplier of his expectations
regarding classification of surfaces.
Figure 2 shows typical areas for the zones, which are applied cross programm i.e. irrelevant of
passenger aircraft model.
Cockpit areas (incl freighters) are considered outside of this European standard and need to be defined
on demand between OEM, supplier and customer. The exception to this, is furniture, e.g. lavatories or
crew rest that share common walls with the cabin.
Freighters, currier or crew perceived or frequented areas i.e. cabin linings/furniture are “A” zones,
cargo areas are considered outside this classification and need to be defined on demand between OEM,
supplier and customer.
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SIST EN 4726:2019+AC:2019
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Key
1 Outboard side of a window shade is C zone. Inboard A zone
2 Side wall stowage lid shown open to view lid inside
3 Window funnel interior is A zone
NOTE 1 Endcaps on over head stowage compartment is not shown.
NOTE 2 LHS lining is a mirror of the RHS.
NOTE 3 Linings- outboard surfaces are generally C zone.
NOTE 4 Linings- inboard surfaces are generally A zone.
A zone
B zone
C zone
Figure 2 — Cabin lining
The Figure 3 to Figure 14 show typical areas for the zones which are applied cross program, i.e.
irrelevant of passenger aircraft model or monument type.
Interior parts of monuments which the cabin crew or passenger potentially frequent, perceive or view,
e.g. lavatories, crew rest, special monuments, etc. are equally governed by the same zone classifications
as for the outside of SFE (or similar status) monuments.
Areas covered by other components or monuments will be considered as “C” zones unless, see 4.4.
8

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a) Typical monument with magazine rack and b) Typical monument without additional
doghouse furnishings
Key
A zone
C zone
Figure 3 — Cabin monument

a) Galley overview
9

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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)



b) Fixed parts e.g. c) Fixed parts e.g. d) SFE trolley: e) Removable parts
ovens, coffee ovens, coffee outside A zone, e.g. SU: First
makers, boilers; no makers, boilers; door inside, 10 cm (4 inch) of
side visible: C zone sides visible: interior: B zone, sides are A zone,
Surrounding gap interior shelves thereafter C zone
makes sides visible etc.: B zone,
then first 10 cm underneath:
(4 inch) of sides C zone, tyres
are A zone factory new
thereafter C zone
Key
1 Walls for fixed parts e.g. ovens, boilers: C zone unless gap makes sides visible then first 10 cm
(4 inch): A zone
2 Walls for removable parts e.g. SU first 10 cm (4 inch) is A zone thereafter C zone
3 Stowage inside: B zone incl. door inside trolley doors inside
4 Underneath is C zone
5 Underneath is B zone, because it cannot be directly viewed; if higher this will become an A zone

NOTE Supplied used BFE units e.g. trolleys or standard units etc. shall not be part of an inspection concerning
aesthetical deviations, only new and SFE are eligible. Zonal areas are dedicated to the parts in questions according
to the expected operational status, i.e. with full compliment of inserts, trollies, standard units etc.
A zone
B zone
C zone
Figure 4 — Galley
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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
Figure 5 shows a typical economy seat. Zones might change with position. Figure 5 shows an example in
order to demonstrate the applied theory.

Key
1 Rear sides: if free standing or has any kind of seating behind: A zone. If last row and screened off by
a wall: B zone
2 Underneath head cloths (if present): due to the fact, they are not permanent and may be removed in
the future: A zone
3 Aisle sides: if aisle side: A zone. If window side: B zone (or next to a structure which screens off
viewing the side in question)
4 Underneath armrest: if movable: A zone, if fixed: B zone
5 Tables and mechanisms (incl. hidden in armrest): top and bottom i.e. all sides (incl. IFE if present):
A zone
6 Underneath seat: if “with footrest” movable or fixed: B zone. Top of footrest and mechanism when
deployed: A zone. Non visible sides when deployed: B zone
NOTE 1 Passenger/crew used furniture directly viewed in open operating position:
Compartments inside: B zone
(assuming surfaces mainly hidden by supplied amenities), Areas of compartments which can be
directly viewed when open and seated: A zone
NOTE 2 Lids/flaps inside/outside: A zone
Figure 5 — Economy passenger seat
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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
Figure 6 shows a typical business class seat. Zones might change with position. Figure 6 shows an
example in order to demonstrate the applied theory.

Key
1 Stowages insides: B zone
2 Rear walls, if free standing: A zone; if rear side very close to a wall (i.e. masked by wall): B zone
3 Aisle walls, if aisle side: A zone; if window side: B zone
4 Underneath, if “footrest” returns down and backwards: B zone; if “footrest” returns up and
backwards: A zone; if “footrest” cannot be viewed incl. during operational movement: C zone
5 Reade side: A zone
6 Stowage insides: B zone
7 Tables top and bottom: A zone
8 LCD monitor: A zone
A zone
B zone
Figure 6 — Business class passenger seat
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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
Figure 7 to Figure 12 show a typical First class seat. Zones might change with position. Figure 7 to
Figure 12 show an example in order to demonstrate the applied theory.

Key
1 Hidden sides: not able to be viewed are B zone
2 Inside open cupboards: could be a B zone on the “shadow side only” according to the direct viewing
rules, (assuming this side is not visible when entering the compartment), otherwise A zone
3 Moving furniture parts: if, when operating the table, all sides are revealed, then all A zone
(underside B zone, only if never viewable)
4 Recessed areas: only ones not naturally visible are B zone
A zone
B zone
C zone
Figure 7 — Typical first class minisuite – inside, front view (looking forward)
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EN 4726:2018+AC:2019 (E)

Key
1 blocked off areas: C zone
2 Stowages inside: B zone, incl. door inside
3 Undersides: B zone, unless they can be viewed from other natural positions e.g. sleep, then A zone
4 Covered areas: C zone, areas hidden e.g. by the seat, but run into an A zone at the top. In cases of
contention, the highest quality is default. To establish zonal transitions/boundaries, all
permutations of natural/possible usage viewing angles are vectored in
5 Recessed areas: only ones not naturally visisble are B zone. If visible when entering minisuite then
A zone
6 Blocked off areas: C zone
A zone
B zone
C zone
Figure 8 — Typical first class credenza, side view (looking forward)
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EN 4726:2018+AC:2019 (E)

Key
1 Passenger seat used furniture directly viewed in open or operating position: compartments inside:
B zone (assuming surfaces mainly hidden by supplied amenities), Areas of compartment which can
be directly viewed when open and seated: A zone
2 Lids/flaps inside/outside: A zone
3 Tops: A zone (unless so high it cannot be viewed from a standing position i.e. over 1,90 m
(74.8 inch))
A zone
B zone
Figure 9 — Typical first class minisuite with table deployed and doors open, plan view
(looking from top)

Key
1 Plastic screens: A zone (unless otherwise pre-agreed due to manufacturing tolerances)
2 Areas behind moving parts: C zone, incl. door inside areas, as long as they are never visible
(rest: A zone)
A zone
C zone
Figure 10 — Typical first class minisuite – outside, doors shown closed, side view
(looking outboard)
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EN 4726:2018+AC:2019 (E)

Key
1 Blocked off areas: C zone
2 Parts close to each other: A zone (where clearly visible)
3 Shadowed parts: B zone which will transition to an A zone e.g. the seat and wall are relatively close,
the bottom of these parts are in shadow and cannot be clearly perceived. In case of contention, the
highest quality is default (to establish zonal transitions/boundaries – all permutations of
natural/possible usage viewing angles are vectored in)
A zone
B zone
C zone
Figure 11 — Typical first class minisuite – inside, doors shown closed, side view
(looking inboard)

Key
1 Covered area (this side only): C zone
2 Underneath: B zone
A zone
B zone
Figure 12 — Typical first class minisuite seat
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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
Figure 13 shows a typical cabin attendant seat. Zones might change with position. Figure 13 shows an
example in order to demonstrate the applied theory.
Figure 13 shows typical areas for the zonal classification. Areas/parts allowing functional manual or
driven movement; thereby becoming fully visible to the passenger or cabin crew are classed as “A”
zones. In some cases the installation position is paramount, facets covered up of wall flush items will
have an upgraded classification if free standing.

Key
1 Only if flush to a wall: B zone behind headrest, back of seat
2 A zone, under seat pan shroud, underneath of footrest
A zone
B zone
Figure 13 — Cabin attendant seat
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EN 4726:2018+AC:2019 (E)
Figure 14 shows a doghouse, which depends on position in aircraft. Zones might change with position.
Figure 14 shows an example in order to demonstrate the applied theory.

Key
1 Corpus outside: A zone; if masked by wall, seat, etc. visible area: B zone, any areas completely not
visible: C zone
2 Corpus inside: B zone; if part of inside not visible by normal operation: C zone
3 Drawer and door inside: B zone
4 Door outside: A zone
5 Drawer bottom: C zone
6 Corpus bottom inside: C zone
7 Corpus bottom: C zone
8 Backside if outboard lateral side: B zone; if free standing: A zone
A zone
B zone
C zone
Figure 14 — Example of doghouse
4.4 Exception to classification of surfaces
If the customer has an accepted Request for Change (RFC)/Specific Change Note (SCN) to upgrade a
particular area of a monument, e.g. the inside of a stowage door, the door inside shall become an A zone
surface instead of an B zone.
4.5 Split lines, definition, cutting and placement of decorative materials and sealing
4.5.1 General
Split lines refer to the physical split of decorative material and not to a pattern alignment which is
covered in 4.5.3. Decor split line positions are defined by the pertinent OEM department under
advisement and in conjunction with the supplier so as to include all aspects of design prerequisites and
feasibility.
Split lines are inherent to a successful and controllable development and in some cases a necessity to
achieve pattern harmony; therefore a split line or its position cannot be accepted as a reason for
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SIST EN 4726:2019+AC:2019
EN 4726:2018+AC:2019 (E)
customer rejection. Due to the complex nature of the definition process split lines are shown in the
corresponding colour specification to provide design direction and understanding.
4.5.2 General split line rules for decorative materials
General split line rules for decorative materials are:
a) Any applied film, split line position tolerance is 2 mm, i.e. ±1 mm (0.079 inch ± 0.039 inch) on
curved or wavy surfaces and shall be 1 mm, i.e. ±0,5 mm (0.039 inch ± 0.02 inch) on purely flat
surfaces. For decorative sheet material (DSM) film see 4.5.3 b.
b) In cases of split line production templates, the templates may also be used for quality inspection
checks.
c) Split line necessity overrules aesthetic reasoning.
d) Parts with integrated deep recesses or 3D shapes surpass most technical solutions for films and
therefore generally split lines shall be set or a different medium chosen.
e) Decorative Sheet Material (DSM) (formally known as PVF film) split lines are always overlapped by
10 mm (0.393 inch) and if wrapped around edges, e.g. doors, etc. shall also have a minimum of
10 mm (0.393 inch) wrap around. Reinforced material (DSM film) is always butt jointed.
f) All split lines in all mediums are optically straight, neat (no over spray by painting) and run parallel
to edges, i.e. vertical or horizontal, unless otherwise defined. If a split line is noticeable to the eye,
i.e. slanted it is considered a defect. Butt joint edges cover the substrate panel completely, i.e.
nothing of the panel is visible through the butt joint.
g) Split lines are as a rule visible and are therefore so acceptable, although the goal is always to make
them as least obvious as possible.
h) Split lines for Hydro Transfer Printing Technology (HTPT) have a different set of rules and can be
found in the HTPT document.
i) Paint split lines whereby two different colours meet on a single part shall have a smooth transition,
i.e. no noticeable (to the touch) paint depth difference at the edge (supplier to provide samples for
acceptance).
j) DSM cut edges are never left exposed except when an overlap is defined.
k) Split lines that are not to the OEM interior colour specifications i.e. definitions are considered a
defect and shall be re-worked.
4.5.3 Pattern alignment over two or more sheets/parts
Pattern alignment over two or more sheets/parts are:
a) Pattern alignment refers generally to the printed decorative layer of a Decorative Sheet Material
(DSM) film. Non-standard materials that are embossed, engraved, textile, natural products,
imitations of natural products, suspended compounds and special effects or have a structured
surfaces etc. shall be handled on a case by case method during the prototyping phase and thereby
the parameters documented by the manufacturer and submitted to the OEM for validation.
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b) The Decorative Sheet Material (DSM) expands and contracts under varying environmental
conditions which are apparent during production, stowage and ultimately application. Hence
perfect pattern alignment across two decor sheets is not possible due to these mechanical
properties inherent in the manufacturing. However it is possible to align one control point within
the pattern, this control point and the position thereof is defined in the appropriate OEM Interior
Colour Specification (ICS), deviations from the ICS are regarded as defects and shall be reworked.
Any DSM defined control point position has a tolerance of 2 mm, i.e. ±1 mm
(0.079 inch ± 0.039 inch) on purely flat surfaces and on curved or wavy surfaces it is 4 mm,
i.e. ±2 mm (0.158 inch ± 0.079 inch).
c) Symmetrical patterns whether produced by silk screen or digital will show a degree of “pattern
warping” as already mentioned, this is inherent to the manufacturing process and is thereby not
considered a cosmetic defect. The tolerances shall be assessed and agreed upon by the OEM and the
manufacturer, latest at the material First Article Inspection (FAI). A full size actual production sheet
is sent to the OEM for archiving and thereby a record of each agreement.
d) These rules apply in vertical and horizontal axis or in some unusual cases at a predefined angle as
listed in the appropriate OEM colour specifications. See pictorial and simplified examples in
Figure 15 for basic rules about acceptance.
e) Unusual decors shall have their own additional set of rules, these shall be defined in the pertinent
OEM interior colour specification for orientation or/and documentation of exception.
f) If pattern and/or texture alignment is good but the wrong formats have been used i.e. against
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