IEC 60793-2-60:2025

IEC 60793-2-60 ®
Edition 2.0 2025-09
INTERNATIONAL
STANDARD
REDLINE VERSION
Optical fibres -
Part 2-60: Product specifications - Sectional specification for class C single-
mode interconnection fibres
ICS 33.180.10 ISBN 978-2-8327-0756-2
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CONTENTS
FOREWORD . 3
1 Scope . 1
2 Normative references . 6
3 Terms, definitions, symbols, and abbreviated terms . 7
3.1 Terms and definitions. 7
3.2 Symbols and abbreviated terms . 7
4 Specifications . 7
4.1 General . 7
4.2 Dimensional requirements . 8
4.3 Mechanical requirements . 9
4.4 Transmission requirements . 9
4.5 Environmental requirements . 10
4.5.1 General . 10
4.5.2 Transmission requirements . 11
4.5.3 Mechanical requirements . 11
Annex A (normative) Family specification for C1 single-mode fibres. 13
A.1 IntroductionGeneral . 13
A.2 Dimensional requirements . 13
A.3 Mechanical requirements . 13
A.4 Transmission requirements . 14
A.5 Environmental requirements . 14
A.5.1 General . 14
A.5.2 Transmission requirements . 14
A.5.3 Mechanical requirements – Coating strip force . 15
Annex B (normative) Family specification for C2 single-mode fibres. 16
B.1 IntroductionGeneral . 16
B.2 Dimensional requirements . 16
B.3 Mechanical requirements . 16
B.4 Transmission requirements . 17
B.5 Environmental requirements . 17
B.5.1 General . 17
B.5.2 Transmission requirements . 17
B.5.3 Mechanical requirements – Coating strip force . 17
Annex C (normative) Family specification for C3 single-mode fibres . 18
C.1 IntroductionGeneral . 18
C.2 Dimensional requirements . 18
C.3 Mechanical requirements . 18
C.4 Transmission requirements . 19
C.5 Environmental requirements . 19
C.5.1 General . 19
C.5.2 Transmission requirements . 19
C.5.3 Mechanical requirements – Coating strip force . 19
Annex D (normative) Family specification for C4 single-mode fibres . 20
D.1 IntroductionGeneral . 20
D.2 Dimensional requirements . 20
D.3 Mechanical requirements . 20
D.4 Transmission requirements . 21
D.5 Environmental requirements . 21
D.5.1 General . 21
D.5.2 Transmission requirements . 21
D.5.3 Mechanical requirements – Coating strip force . 21
Bibliography . 22

Table 1 – List of families and main differences . 8
Table 2 – Dimensional attributes and measurement methods . 8
Table 3 – Requirements common to class C fibres . 9
Table 4 – Mechanical attributes and measurement methods . 9
Table 5 – Mechanical requirements common to class C fibres . 9
Table 6 – Transmission attributes and measurement methods . 10
Table 7 – Transmission requirements common to class C fibres . 10
Table 8 – Transmission attributes required in family specifications . 10
Table 9 – Environmental attributes and test methods . 10
Table 10 – Environment-dependent mechanical or transmission attributes and test
methods . 11
Table 11 – Tensile strength requirements common to class C fibres . 11
Table 12 – Stress corrosion susceptibility requirements common to class C fibres . 12
Table A.1 – Dimensional requirements for C1 fibres. 13
Table A.2 – Mechanical requirements for C1 fibres . 14
Table A.3 – Transmission requirements for C1 fibres . 14
Table A.4 – Environment-dependent transmission requirements for C1 fibres . 15
Table A.5 – Environment-dependent mechanical requirements for C1 fibres . 15
Table B.1 – Dimensional requirements for C2 fibres. 16
Table B.2 – Mechanical requirements for C2 fibres . 16
Table B.3 – Transmission requirements for C2 fibres . 17
Table B.4 – Environment-dependent transmission requirements for C2 fibres . 17
Table B.5 – Environment-dependent mechanical requirements for C2 fibres . 17
Table C.1 – Dimensional requirements for C3 fibres . 18
Table C.2 – Mechanical requirements for C3 fibres . 18
Table C.3 – Transmission requirements for C3 fibres . 19
Table C.4 – Environment-dependent transmission requirements for C3 fibres . 19
Table C.5 – Environment-dependent mechanical requirements for C3 fibres . 19
Table D.1 – Dimensional requirements for C4 fibres . 20
Table D.2 – Mechanical requirements for C4 fibres . 20
Table D.3 – Transmission requirements for C4 fibres . 21
Table D.4 – Environment-dependent transmission requirements for C4 fibres . 21

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Optical fibres -
Part 2-60: Product specifications - Sectional specification
for class C single-mode interconnection fibres

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
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Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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6) All users should ensure that they have the latest edition of this publication.
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
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the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes made
to the previous edition IEC 60793-2-60:2008. A vertical bar appears in the margin wherever a
change has been made. Additions are in green text, deletions are in strikethrough red text.

IEC 60793-2-60 has been prepared by subcommittee 86A: Fibres and cables, of IEC technical
committee 86: Fibre optics. It is an International Standard.
This second edition cancels and replaces the first edition published in 2008. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) replacement of "intraconnection" with "interconnection" and addition of the definition of
"interconnection fibres";
b) modification of the nominal MFD limit of C1 fibres;
c) addition of "Primary coating diameter-coloured" limits for class C fibres and change of
"Primary coating diameter-uncoloured" limits for class C_80 fibres;
d) change of coating strip force limits for class C1, class C2, and class C3 fibres;
e) replacement of "Fibre cut-off wavelength" with "Cable cut-off wavelength" and revision of
"Note b" in Table 6;
f) replacement of "Fibre cut-off wavelength" with "Cable cut-off wavelength" and deletion of
the "Note" in Table 8;
g) addition of 200 μm coating diameter requirements for C1_125 fibres and change of coating
diameters limits for C1_80 fibres in Table A.1;
h) addition of 200 µm coating diameter requirements for C1_125 fibres and change of coating
strip force limits in Table A.2 and in Table A.5;
i) replacement of "Fibre cut-off wavelength" with "Cable cut-off wavelength", modification of
the "Cable cut-off wavelength" limit and addition of a new "Note" in Table A.3;
j) addition of a transmission requirements at 1 625 nm and deletion of 1 310 nm for C1 fibres
in Table A.4;
k) modification of "Fibre cut-off wavelength" limits of C3 fibres in Table C.3;
l) replacement of "Fibre cut-off wavelength" with "Cable cut-off wavelength" for C4 fibres in
Table D.3.
The text of this International Standard is based on the following documents:
Draft Report on voting
86A/2599/FDIS 86A/2617/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 60793 series, published under the general title Optical fibres can
be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
1 Scope
This part of IEC 60793 is applicable to optical fibre types C1, C2, C3, and C4, as described in
Table 1. These fibres are used for the intraconnections interconnections within or between
optical components or photonic systems or subsystems and are optimized to support dense
optical connectivity. While the fibres are sold in lengths on the scale of kilometres, they are
normally cut into short lengths for use in these intraconnections. While the fibres could can be
overcoated or buffered for the purpose of making protected pigtails, they may can be used
without overcoating. They may can, however, be colour coded.
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.
IEC 60793-1-20, Optical fibres - Part 1-20: Measurement methods and test procedures - Fibre
geometry
IEC 60793-1-21, Optical fibres - Part 1-21: Measurement methods and test procedures -
Coating geometry
IEC 60793-1-22, Optical fibres - Part 1-22: Measurement methods and test procedures - Length
measurement
IEC 60793-1-30, Optical fibres - Part 1-30: Measurement methods and test procedures - Fibre
proof test
IEC 60793-1-31, Optical fibres - Part 1-31: Measurement methods and test procedures - Tensile
strength
IEC 60793-1-32, Optical fibres - Part 1-32: Measurement methods and test procedures -
Coating strippability
IEC 60793-1-33, Optical fibres - Part 1-33: Measurement methods and test procedures - Stress
corrosion susceptibility
IEC 60793-1-40, Optical fibres - Part 1-40: Attenuation measurement methods and test
procedures – Attenuation
IEC 60793-1-44, Optical fibres - Part 1-44: Measurement methods and test procedures - Cut-
off wavelength
IEC 60793-1-45, Optical fibres - Part 1-45: Measurement methods and test procedures - Mode
field diameter
IEC 60793-1-46, Optical fibres - Part 1-46: Measurement methods and test procedures –

Monitoring of changes in optical transmittance attenuation
IEC 60793-1-47, Optical fibres - Part 1-47: Measurement methods and test procedures -
Macrobending loss
IEC 60793-1-50, Optical fibres - Part 1-50: Measurement methods and test procedures - Damp
heat (steady state) tests
IEC 60793-1-51, Optical fibres - Part 1-51: Measurement methods and test procedures - Dry
heat (steady state) tests
IEC 60793-1-52, Optical fibres - Part 1-52: Measurement methods and test procedures -
Change of temperature tests
IEC 60793-2, Optical fibres - Part 2: Product specifications - General
IEC/TR 61931, Fibre optic – Terminology
3 Terms, definitions, symbols, and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions related to testing given in
IEC 61931, as well as the terms and definitions related to fibres given in IEC 60793-2, and the
following apply. Moreover, the definitions of the specified attributes are contained in the test
methods.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1.1
interconnection fibre
fibre up to 1 km long that is used within or between optical components or systems to support
dense connectivity
3.2 Symbols and abbreviated terms
The following symbols and abbreviated terms are used in this document:
F average strip force
avg
F peak strip force
peak
MFD mode field diameter
n stress corrosion parameter – dynamic
d
4 Specifications
4.1 General
The general requirements defined in IEC 60793-2 apply to these fibres. Specific requirements
that are common to these fibres are found in the body of this text. Particular requirements for
individual fibre types or applications are defined in Annex A, Annex B, Annex C and Annex D,
which refer to normative family specifications. These family specifications are distinguished
based on optimum transmission wavelengths and nominal mode field diameter (MFD), which
affects splice loss.
For each family specification, there are two sub-categories that are distinguished on the basis
of the cladding diameter and other related attributes. The conventional nominal cladding
diameter of 125 μm is augmented by the reduced cladding type product with a nominal diameter
of 80 μm. These are distinguished with suffixes "_125" or "_80". For example, the C1 fibre can
be selected as either "C1_125" or "C1_80". The transmission characteristics of both the
cladding diameter choices should be the same.
For each family specification except C1, there are two sub-categories that are distinguished on
the basis of transmission characteristics that relate to MFD. To denote these sub-categories,
suffix "_a" or "_b" is added, for lower or higher MFD. In general, the fibres can be optimised for
either splice loss or macro-bend loss or both using MFD as a main variable. A C2 fibre with an
80 μm cladding diameter and lower MFD is designated as C2_80_a.
Fibres for the C1_125 family specification can be selected from category B1.1 or B1.3 B-652.B
or B-652.D or B-657 single-mode fibres and are suitable for use with any category class B
single-mode fibre at wavelengths from 1 280 1 260 nm to 1 625 nm. Fibres for the C2 and C3
family specifications are optimized at nominal wavelengths of 1 310 nm and 1 550 nm
respectively for connection to any category class B single-mode fibre. Fibres for the C4 family
specification are optimized for transporting optical amplifier pump light at 980 nm or higher.
Table 1 – List of families and main differences
Families Nominal transmission wavelengths Nominal MFDs
nm
C1 1 260, 1 310, 1 550 and 1 625 8,6 to 9,5 9,2 μm at 1 310 nm
C2 1 310 5,0 to 7,0 μm at 1 310 nm
C3 1 550 and 1 625 5,5 to 7,5 μm at 1 550 nm
C4 980 4,0 to 7,0 μm at 980 nm

The fibre shall consist of a glass core, a glass cladding, and a coating in accordance with 5.1
5.3 of IEC 60793-2:2019.
4.2 Dimensional requirements
Dimensional attributes and measurement methods that may be specified are given in Table 2.
Minimum requirements, common to all fibres in this category, are given in Table 3. Table 2
specifies both the dimensional attributes and the corresponding measurement methods that
shall be applied. Minimum dimensional requirements, common to all Class C fibres, shall be as
specified in Table 3. Some family specification requirements may can be stricter.
Table 2 – Dimensional attributes and measurement methods
Attributes Tests Measurement
methods
Cladding diameter IEC 60793-1-20
Cladding non-circularity IEC 60793-1-20
Core concentricity error IEC 60793-1-20
Coating diameter IEC 60793-1-21
Coating non-circularity IEC 60793-1-21
Cladding-coating concentricity error IEC 60793-1-21
Fibre length IEC 60793-1-22
Table 3 – Requirements common to class C fibres
Attributes Units _125 Limits _80 Limits
a
μm 125 ± 1,0 80 ± 1,0
Cladding diameter
Cladding non-circularity % ≤ 1,0 ≤ 1,0
Core concentricity error μm ≤ 0,5 ≤ 0,5
Primary coating diameter – μm 235 to 255 155 to 175 150 to
a c
uncoloured
Primary coating diameter – μm 235 to 265 150 to 180
a c
coloured
b b
Fibre length km
a
Tolerance applies to the entire length of fibre.
b
Length requirements vary and should be agreed between customer and supplier.
c
These limits on primary coating diameters are most commonly used. Other
coating diameters shall be specified in the family specifications.

4.3 Mechanical requirements
Mechanical attributes and measurement methods that may be specified are given in Table 4.
Table 4 specifies both the mechanical attributes and the corresponding measurement methods
that shall be applied. Minimum mechanical requirements, common to all fibres in class C, are
given in Table 5. Some family specification values may can be stricter.
Table 4 – Mechanical attributes and measurement methods
Attributes Tests Measurement
methods
Proof test IEC 60793-1-30
Tensile strength IEC 60793-1-31
Coating strippability IEC 60793-1-32
Stress corrosion susceptibility IEC 60793-1-33

Table 5 – Mechanical requirements common to class C fibres
Attributes Units Limits
Proof stress level GPa ≥ 0,69
a
The coating shall be mechanically
Coating strip force
strippable. Heat stripping may be
most appropriate for some
coatings
Tensile strength (median) for a GPa ≥ 3,8
0,5 m specimen length
a
The coating strip force is a common requirement for all Class C fibres. Refer to
the Annexes of this document for detailed specifications.

4.4 Transmission requirements
Transmission attributes and measurement methods that may be specified are given in Table 6.
Table 6 specifies both the transmission attributes and the corresponding measurement methods
that shall be applied. Some family specifications may can have additional attributes or test
methods. Minimum transmission requirements, common to all class C fibres, are given shall be
as specified in Table 7. Some family specifications may can be more stringent stricter.
Requirements that shall be specified in the family specifications are listed in Table 8.
Table 6 – Transmission attributes and measurement methods
Attributes Tests Measurement methods
a
Attenuation coefficient
IEC 60793-1-40
b
FibreCable cut-off wavelength
IEC 60793-1-44
Mode field diameter IEC 60793-1-45
Macrobending loss IEC 60793-1-47
a
The attenuation coefficient at various wavelengths can be calculated using the
measured values at a few wavelengths using a spectral model such as the one
given in IEC 60793-1-40. For example, the attenuation at 1 480 nm can be
calculated and used for design of systems that employ remote pumping of optical
amplifiers.
b
Cut-off wavelength intrinsically contains length or bending dependence. In the
case of a short length deployment condition (e.g. a piece length shorter than 22 m
without specific bending), cut-off wavelength under the expected condition should
be ensured to have negligible influence on system performance.

Table 7 – Transmission requirements common to class C fibres
Attributes Units Limits
This table is empty, but retained in case of some
common minimum requirement.
Table 8 – Transmission attributes required in family specifications
Attributes required in family specifications
Maximum attenuation coefficient and wavelength at operating wavelengths
Nominal mode field diameter, tolerance, and wavelength
Maximum macro-bending loss increase, wavelength, bend radius, and number of
turns
Maximum cable cut-off wavelength
Fibre cut-off wavelength
NOTE Fibre cut-off wavelength is the default, but alternative configurations may be
agreed for some applications such as fibre being used on a bobbin. In these cases,
the measured cut-off wavelength values can be generally mapped to the
bend/length conditions for the alternative applications.

4.5 Environmental requirements
4.5.1 General
Environmental attribute tests and measurement methods are documented in two forms:
– various environmental exposure tests are given in Table 9;
– mechanical or transmission attributes that may change when subjected to environmental
exposure are listed in Table 10.
– environmental attributes and the corresponding measurement methods shall be as specified
in Table 9;
– Environment-dependent mechanical or transmission attributes and their corresponding
.
measurement methods shall be as specified in Table 10
Table 9 – Environmental attributes and test methods
Environmental exposures Tests Measurement
methods
Damp heat tests IEC 60793-1-50
Dry heat tests IEC 60793-1-51
Change of temperature tests IEC 60793-1-52

Table 10 – Environment-dependent mechanical
or transmission attributes and test methods
Attributes Test Measurement
methods
Change in optical transmission attenuation IEC 60793-1-46
Attenuation IEC 60793-1-40
Coating strip force IEC 60793-1-32
Tensile strength IEC 60793-1-31
Stress corrosion sensitivity IEC 60793-1-33

These tests are normally conducted periodically as type-tests for a fibre and coating design.
Unless otherwise specified, The recovery period allowed between completing the environmental
exposure and performing the attribute measurements shall be as stated specified in the
particular environmental conditioning test standards listed in Table 9.
4.5.2 Transmission requirements
Change in attenuation from the initial value shall be less than the values specified in the relevant
family specification.
4.5.3 Mechanical requirements
4.5.3.1 General
These tests are, in practice, the most severe requirements amongst the environment exposures
defined in Table 9.
4.5.3.2 Coating strip force
In addition to the un-aged strip force requirements in 4.3, coating strip force after damp heat
ageing shall be specified in the family specifications. The ageing options are also specified.
4.5.3.3 Tensile strength
The attributes given in Table 11 shall be verified following removal of the fibre from the test
environment.
Table 11 – Tensile strength requirements common to class C fibres
Environmen Median tensile 15 % of the tensile strength
t strength (GPa), distribution (GPa),
specimen length: specimen length: 0,5 m
0,5 m
Damp heat ≥ 3,03 ≥ 2,76
NOTE The requirements given in Table 11 do not apply to hermetically coated fibres or to fibres
that are intended for sole use within hermetically sealed enclosures.
4.5.3.4 Stress corrosion susceptibility
The attributes given in Table 12 shall be verified following removal of the fibres from the test
environment.
Table 12 – Stress corrosion susceptibility requirements common to class C fibres
Environment Stress corrosion
Susceptibility constant, n
d
Damp heat ≥ 18
NOTE The requirements given in Table 12 do not apply to hermetically coated fibres or to fibres
that are intended for sole use within hermetically sealed enclosures.

Annex A
(normative)
Family specification for C1 single-mode fibres
A.1 IntroductionGeneral
The C1 single-mode fibre is a single-mode intraconnection interconnection fibre that is suitable
for use with any category B single-mode fibre at wavelengths from 1 280 1 260 nm to 1 625 nm.
It is optimised for precision glass geometry and improved macro-bending, and generally have
lower fibre cut-off wavelength compared to that of B1.1 B-652 fibres.
Clause A.2 to Clause A.5 contain the requirements for C1 fibres. Common requirements, copied
for ease of reference from the sectional specification, are noted by an entry in the “Ref.” column.
Relevant notes from the sectional specification are not repeated but indicated with a superscript.
A.2 Dimensional requirements
Table A.1 contains dimensional requirements for C1 fibres.
Table A.1 – Dimensional requirements for C1 fibres
Attributes Units _125 limits _125 limits _80 limits Ref.
(250 μm coating) (200 μm coating)
Cladding diameter μm 125,0 ± 0,7 80 ± 1,0 4.2
125,0 ± 0,7
Cladding non-circularity % ≤ 0,7 ≤ 0,7 ≤ 1,0 4.2
Core concentricity error μm ≤ 0,5 ≤ 0,5 ≤ 0,5 4.2
a
Primary coating diameter – μm 235 to 255 155 to 175 150 to 4.2
180 to 210
uncoloured 170
a
Primary coating diameter – μm 235 to 265 150 to 180 4.2
180 to 220
coloured
Fibre length km (See 4.2) (See 4.2) (See 4.2) 4.2
a
These limits on primary coating diameters are most commonly used. There are other applications, such
as fibres for use within optical sub-systems, pigtails, or specialty applications, which use other primary
coating diameters such as 150 μm to 170 μm uncoloured and 150 μm to 180 μm coloured

A.3 Mechanical requirements
Table A.2 contains mechanical requirements for C1 fibres.
Table A.2 – Mechanical requirements for C1 fibres
Attributes Units _125 limits _125 limits _80 limits Ref.
(250 μm (200 μm coating)
coating)
Proof stress level GPa ≥ 0,69 4.3
Coating strip force N 1,0 ≤ F ≤ 5,0 0,4 ≤ F ≤ 5,0 1,0 0,4 ≤ F ≤ 5,0 4.3
avg avg avg
(average)
Coating strip force (peak) N 1,0 ≤ F ≤ 0,4 ≤ F ≤ 8,9 0,4 ≤ F ≤ 8,9 4.3
peak peak peak
8,9
Tensile strength (median) GPa ≥ 3,8 4.3
for 0,5 m specimen
length
A.4 Transmission requirements
Table A.3 contains transmission requirements for C1 fibres. The specified limits apply to both
_125 and _80 fibres.
Table A.3 – Transmission requirements for C1 fibres
Attributes Units Limits Ref.
Attenuation coefficient dB/km ≤ 0,7 4.4
from 1 310 1 260 nm to 1 625 nm
Mode field diameter range of nominal values at 1 310 nm µm 8,6 to 9,5 9,2 4.4
Mode field diameter tolerance ± 0,4 4.4
µm
FibreCable cut-off wavelength nm ≤ 1 280 1 260 4.4
Macro-bending loss at 1 625 nm, dB ≤ 1,0 4.4
5 turns on a 16 mm radius mandrel
a
Cut-off wavelength intrinsically contains length or bending dependence. In the case of a short length
deployment condition (e.g. a piece length shorter than 22 m without specific bending), cut-off wavelength under
the expected condition should be ensured to have negligible influence on system performance.

A.5 Environmental requirements
A.5.1 General
Subclause A.5.2 and A.5.3 contain requirements specific to C1 fibres. The specified limits apply
to all sub-categories.
A.5.2 Transmission requirements
Change in attenuation from the initial value shall be less than the values specified in Table A.4.
Attenuation shall be measured periodically during the entire exposure to each environment and
after removal.
Table A.4 – Environment-dependent transmission requirements for C1 fibres
Environment Wavelengths Maximum attenuation increase
nm dB/km
Damp heat 1 310 1 550 ≤ 0,10
1 550 1 625 ≤ 0,10
Dry heat 1 310 1 550 ≤ 0,10
1 550 1 625 ≤ 0,10
Change of temperature 1 310 1 550 ≤ 0,10
1 550 1 625 ≤ 0,10
A.5.3 Mechanical requirements – Coating strip force
Table A.5 shows attributes that shall be verified following removal of the fibre from the test
environment.
Table A.5 – Environment-dependent mechanical requirements for C1 fibres
Environment Average strip force Peak strip force
N N
_125 Damp heat 1,0 ≤ F ≤ 5,0 1,0 ≤ F ≤ 8,9
avg peak
(250 μm coating)
_125 Damp heat 0,4 ≤ F ≤ 5,0 0,4 ≤ F ≤ 8,9
avg peak
(200 μm coating)
_80 Damp heat 1,0 0,4 ≤ F ≤ 5,0 0,4 ≤ F ≤ 8,9
avg peak
Annex B
(normative)
Family specification for C2 single-mode fibres
B.1 IntroductionGeneral
The C2 single-mode fibre is a reduced bend loss single-mode intraconnection interconnection
fibre that is optimized for loss performance in the 1 310 nm region.
Clause B.2 to Clause B.5 contain the requirements for C2 fibres. Common requirements, copied
for ease of reference from the sectional specification, are noted by an entry in the “Ref.” column.
Relevant notes from the sectional specification are not repeated but indicated with a superscript.
B.2 Dimensional requirements
Table B.1 contains dimensional requirements for C2 fibres. The specified limits apply to both
“_a” and “_b” sub-categories.
Table B.1 – Dimensional requirements for C2 fibres
Attributes Units _125 _80 limits Ref.
limits
Cladding diameter μm 125,0 ± 80,0 ± 1,0 4.2
1,0
Cladding non-circularity % ≤ 1,0 ≤ 1,0 4.2
Core concentricity error μm ≤ 0,5 ≤ 0,5 4.2
Primary coating diameter – μm 235 to 155 to 175 150 to 4.2
uncoloured 255 170
Primary coating diameter – μm 235 to 150 to 180 4.2
coloured 265
Fibre length km (See 4.2) (See 4.2) 4.2

B.3 Mechanical requirements
Table B.2 contains mechanical requirements for C2 fibres. The specified limits apply to both
“_a” and “_b” sub-categories.
Table B.2 – Mechanical requirements for C2 fibres
Attributes Units _125 limits _80 limits Ref.

Proof stress level GPa ≥ 0,69 4.3
Coating strip force N 1,0 ≤ F ≤ 5,0 1,0 0,4 ≤ F ≤ 5,0 4.3
avg avg
(average)
Coating strip force N 1,0 ≤ F ≤ 8,9 0,4 ≤ F ≤ 8,9 4.3
peak peak
(peak)
Tensile strength
GPa ≥ 3,8 4.3
(median) for 0,5 m
specimen length
B.4 Transmission requirements
Table B.3 contains transmission requirements for C2 fibres. The specified limits apply to both
80 μm and 125 μm nominal cladding diameter sub-categories.
Table B.3 – Transmission requirements for C2 fibres
Attributes Units _a limits _b limits Ref.
Attenuation coefficient at 1 310 nm dB/km ≤ 0,75 ≤ 0,75 4.4
Mode field diameter range of nominal values at μm 5,0 to 6,0 6,1 to 7,0 4.4
1 310 nm
Mode field diameter tolerance μm ± 0,75 ± 0,75 4.4
Fibre cut-off wavelength nm ≤ 1 280 ≤ 1 280 4.4
Macro-bending loss at 1 550 nm, 5 turns on a 10 mm dB ≤ 0,02 ≤ 0,05 4.4
radius mandrel
B.5 Environmental requirements
B.5.1 General
Subclause B.5.2 and B.5.3 contain requirements specific to C2 fibres. The specified limits apply
to all sub-categories.
B.5.2 Transmission requirements
Change in attenuation from the initial value shall be less than the values in Table B.4.
Attenuation shall be measured periodically during the entire exposure to each environment and
after removal.
Table B.4 – Environment-dependent transmission requirements for C2 fibres
Environment Wavelengths Maximum attenuation increase
nm dB/km
Damp heat 1 310 ≤ 0,10
Dry heat 1 310 ≤ 0,10
Change of temperature 1 310 ≤ 0,10

B.5.3 Mechanical requirements – Coating strip force
Table B.5 shows attributes that shall be verified following removal of the fibres from the test
environment.
Table B.5 – Environment-dependent mechanical requirements for C2 fibres
Environment Average strip force Peak strip force
N N
_125 Damp heat 1,0 ≤ F ≤ 5,0 1,0 ≤ F ≤ 8,9
avg peak
_80 Damp heat 1,0 0,4 ≤ F ≤ 5,0 0,4 ≤ F ≤ 8,9
avg peak
Annex C
(normative)
Family specification for C3 single-mode fibres
C.1 IntroductionGeneral
The C3 single-mode fibre is a reduced bend loss single-mode intraconnection interconnection
fibre that is optimized for loss performance in the 1 550 nm region.
Clause C.2 to Clause C.5 contain the requirements for C3 fibres. Common requirements, copied
for ease of reference from the sectional specification, are noted by an entry in the “Ref.” column.
Relevant notes from the sectional specification are not repeated but indicated with a superscript.
C.2 Dimensional requirements
Table C.1 contains dimensional requirements for C3 fibres. The specified limits apply to both
“_a” and “_b” sub-categories.
Table C.1 – Dimensional requirements for C3 fibres
Attributes Units _125 _80 limits Ref.
limits
Cladding diameter μm 125,0 ± 1,0 80,0 ± 1,0 4.2
Cladding non-circularity % ≤ 1,0 ≤ 1,0 4.2
Core concentricity error μm ≤ 0,5 ≤ 0,5 4.2
Primary coating diameter – μm 235 to 255 155 to 175 150 to 4.2
uncoloured 170
Primary coating diameter – μm 235 to 265 150 to 180 4.2
coloured
Fibre length km (See 4.2) (See 4.2) 4.2

C.3 Mechanical requirements
Table C.2 contains mechanical requirements for C3 fibres. The specified limits apply to both
“_a” and “_b” sub-categories.
Table C.2 – Mechanical requirements for C3 fibres
Attributes Units _125 limits _80 limits Ref.

Proof stress level GPa ≥ 0,69 4.3
Coating strip force N 1,0 ≤ F 5,0 1,0 0,4 ≤ F ≤ 5,0 4.3
avg avg
(average)
Coating strip force N 1,0 ≤ F ≤ 8,9 0,4 ≤ F ≤ 8,9 4.3
peak peak
(peak)
Tensile strength GPa ≥ 3,8 4.3
(median) for 0,5 m
specimen length
C.4 Transmission requirements
Table C.3 contains transmission requirements for C3 fibres. The specified lim
...