IEC 60794-6-20:2020

IEC 60794-6-20 ®
Edition 1.0 2020-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibre cables –
Part 6-20: Indoor-outdoor cables – Family specification for flame retardant
outdoor cables
Câbles à fibres optiques –
Partie 6-20: Câbles intérieurs/extérieurs – Spécification de famille pour
les câbles extérieurs retardateurs de flamme

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IEC 60794-6-20 ®
Edition 1.0 2020-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Optical fibre cables –
Part 6-20: Indoor-outdoor cables – Family specification for flame retardant

outdoor cables
Câbles à fibres optiques –
Partie 6-20: Câbles intérieurs/extérieurs – Spécification de famille pour

les câbles extérieurs retardateurs de flamme

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-8908-2

– 2 – IEC 60794-6-20:2020 © IEC 2020
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 7
4 General specifications . 7
4.1 Optical fibres . 7
4.2 Cable elements . 7
5 Specifications for flame retardant outdoor cables – Construction . 8
6 Details of family specifications and test conditions for flame retardant outdoor
cables. 8
6.1 Applicable tests . 8
6.2 Mechanical tests . 9
6.2.1 General . 9
6.2.2 Tensile performance . 10
6.2.3 Abrasion . 10
6.2.4 Crush . 11
6.2.5 Impact . 11
6.2.6 Repeated bending . 11
6.2.7 Torsion . 12
6.2.8 Bend . 12
6.2.9 Bending under tension . 12
6.2.10 Kink . 12
6.2.11 Rip cord functional test . 12
6.3 Environmental tests . 13
6.3.1 Temperature cycling . 13
6.3.2 Water penetration . 13
6.3.3 Ageing . 14
6.3.4 UV resistance . 14
6.3.5 Environmental stress cracking . 14
6.3.6 Cable external freezing . 14
6.3.7 Compound flow . 15
6.3.8 Bleeding and evaporation . 15
6.3.9 Material compatibility . 15
6.4 Cable element tests . 15
6.4.1 Ribbon strippability . 15
6.4.2 Ribbon tear (separability) . 15
6.4.3 Ribbon dimensions and geometry . 16
6.4.4 Ribbon torsion . 16
6.4.5 Ribbon residual twist . 16
6.4.6 Tube kinking . 16
6.4.7 Bend test for optical cable elements . 16
6.4.8 Stripping force stability of cabled fibres . 16
6.5 Other tests . 17
6.5.1 Fire performance . 17
6.5.2 Electrical continuity of cable metallic elements . 17
6.5.3 Thickness of non-metallic sheath . 17
6.5.4 Overall dimensions . 17

Annex A (informative) Examples of flame retardant (FR) outdoor cables . 19
Bibliography . 20

Figure A.1 – Example of a stranded FR outdoor cable design . 19
Figure A.2 – Example of an FR outdoor cable with a central tube design . 19

Table 1 – Tests applicable for mechanical and environmental performance of flame
retardant outdoor cables . 8
Table 2 – Low and high temperatures . 13

– 4 – IEC 60794-6-20:2020 © IEC 2020
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRE CABLES –
Part 6-20: Indoor-outdoor cables –
Family specification for flame retardant outdoor cables

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
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
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
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
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) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60794-6-20 has been prepared by subcommittee SC 86A: Fibres
and cables, of IEC technical committee 86: Fibre optics.
The text of this International Standard is based on the following documents:
FDIS Report on voting
86A/2037/FDIS 86A/2051/RVD
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 60794 series, published under the general title Optical fibre cables,
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 "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

– 6 – IEC 60794-6-20:2020 © IEC 2020
OPTICAL FIBRE CABLES –
Part 6-20: Indoor-outdoor cables –
Family specification for flame retardant outdoor cables

1 Scope
This part of IEC 60794 is a family specification covering optical fibre outdoor cables which are
flame retardant and thus also applicable to indoor environments. These cables generally
possess the characteristics associated with outdoor cable designs having similar thermal and
mechanical robustness that makes them suitable for use in the outside plant, while
simultaneously exhibiting the fire performance required in indoor premises. A typical application
is for example the extension of a "shorter length" of an outdoor cable into the building.
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 60332-1 (all parts), Tests on electric and optical fibre cables under fire conditions – Part 1:
Test for vertical flame propagation for a single insulated wire or cable
IEC 60332-3 (all parts), Tests on electric and optical fibre cables under fire conditions – Part 3:
Test for vertical flame spread of vertically-mounted bunched wires or cables
IEC 60754-2, Test on gases evolved during combustion of materials from cables – Part 2:
Determination of acidity (by pH measurement) and conductivity
IEC 60793-2-10:2019, Optical fibres – Part 2-10: Product specifications – Sectional
specification for category A1 multimode fibres
IEC 60793-2-50:2018, Optical fibres – Part 2-50: Product specifications – Sectional
specification for class B single-mode fibres
IEC 60794-1-1, Optical fibre cables – Part 1-1: Generic specification – General
IEC 60794-1-21, Optical fibre cables – Part 1-21: Generic specification – Basic optical cable
test procedures – Mechanical test methods
IEC 60794-1-22:2017, Optical fibre cables – Part 1-22: Generic specification – Basic optical
cable test procedures – Environmental test methods
IEC 60794-1-23, Optical fibre cables – Part 1-23: Generic specification – Basic optical cable
test procedures – Cable element test methods
IEC 60794-1-24, Optical fibre cables – Part 1-24: Generic specification – Basic optical cable
test procedures – Electrical test methods
IEC 60794-1-31:2018, Optical fibre cables – Part 1-31: Generic specification – Optical cable
elements – Optical fibre ribbon

IEC 60794-1-215, Optical fibre cables – Part 1-215: Generic specification – Basic optical cable
test procedures – Environmental test methods – Cable external freezing test, Method F15
IEC 60794-3:2014, Optical fibre cables – Part 3: Outdoor cables – Sectional specification
IEC 60794-3-10:2015, Optical fibre cables – Part 3-10: Outdoor cables – Family specification
for duct, directly buried and lashed aerial optical telecommunication cables
IEC 60794-4:2018, Optical fibre cables – Part 4: Sectional specification – Aerial optical cables
along electrical power lines
IEC 60794-5:2014, Optical fibre cables – Part 5: Sectional specification – Microduct cabling for
installation by blowing
IEC 60811-202, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 202: General tests – Measurement of thickness of non-metallic sheath
IEC 60811-203, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 203: General tests – Measurement of overall dimensions
IEC 60811-406, Electric and optical fibre cables – Test methods for non-metallic materials –
Part 406: Miscellaneous tests – Resistance to stress cracking of polyethylene and
polypropylene compounds
IEC 61034 (all parts), Measurement of smoke density of cables burning under defined
conditions
ISO 4892-2:2013, Plastics – Methods of exposure to laboratory light sources – Part 2: Xenon-
arc lamps
3 Terms, definitions and abbreviated terms
For the purposes of this document, the terms and definitions given in IEC 60794-1-1 apply.
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 General specifications
4.1 Optical fibres
The optical fibre shall conform to the requirements of IEC 60793-2-10 or IEC 60793-2-50. The
fibre type shall be agreed between the customer and supplier. The cabled fibre shall conform
to IEC 60794-3.
4.2 Cable elements
The cable elements shall conform to IEC 60794-3, IEC 60794-4, IEC 60794-5.

– 8 – IEC 60794-6-20:2020 © IEC 2020
5 Specifications for flame retardant outdoor cables – Construction
The cable design can be derived from a typical outdoor cable design according to the product
specifications described in IEC 60794-3. The specific demand related to flame retardancy will
require the appropriate selection of the jacket material in combination with other material and/or
design considerations. See Annex A for examples of flame retardant outdoor cables.
6 Details of family specifications and test conditions for flame retardant
outdoor cables
6.1 Applicable tests
Compliance with the specification shall be verified by carrying out tests selected from Table 1.
It is not intended that all tests in Table 1 be carried out in all cases. The tests to be applied and
the frequency of testing shall be agreed between the customer and supplier.
Table 1 – Tests applicable for mechanical and environmental
performance of flame retardant outdoor cables
Detail
Characteristics Test methods Remarks
specifications
Mechanical tests  Typically required of most cable
designs
Tensile See 6.2.2 IEC 60794-1-21,
performance
method E1
Abrasion See 6.2.3 IEC 60794-1-21, Method E2A for sheath abrasion
method E2A, method E2B Method E2B, method 2, for
cable marking abrasion
Crush See 6.2.4 IEC 60794-1-21,
method E3A
Impact See 6.2.5 IEC 60794-1-21,
method E4
Repeated bending See 6.2.6 IEC 60794-1-21,
method E6
Torsion See 6.2.7 IEC 60794-1-21,
method E7
Bend See 6.2.8 IEC 60794-1-21, Default method E11A
method E11
Bending under See 6.2.9 IEC 60794-1-21, Diameter of mandrel should be
tension 40 x cable diameter.
method E18A, procedure 1
Load T as defined in 6.2.2.
M
Kink See 6.2.10 IEC 60794-1-21, method E10 Cable kink
Rip cord functional See 6.2.11 IEC 60794-1-21, method E25
Environmental
tests
Temperature See 6.3.1 IEC 60794-1-22,
cycling
method F1
Water penetration See 6.3.2 IEC 60794-1-22, F5B and F5C
method F5
Ageing See 6.3.3 IEC 60794-1-22,
method F9
Characteristics Detail Test methods Remarks
specifications
UV resistance See 6.3.4 IEC 60794-1-22, Some jacket materials are
exempt from this test – see
method F14 (method ISO 4892-
6.3.4
2)
Cable external
See 6.3.6 IEC 60794-1-215,
freezing
method F15A or F15B
Environmental See 6.3.5 IEC 60811-406 Highly filled thermoplastics (e.g.
stress cracking FRNC materials) are sensitive
to stress cracking. The test was
developed for PE and PP and
thus shall be adapted.
Compound flow See 6.3.7 IEC 60794-1-22, method F16
Bleeding and See 6.3.8 IEC 60794-1-23, method G9
evaporation
Material IEC 60794-1-219 should be
See 6.3.9
compatibility applied.
Cable element
tests
Ribbon strippability See 6.4.1 IEC 60794-1-23 If ribbons are used
method G10B
Ribbon tear See 6.4.2 IEC 60794-1-23, If ribbons are used
(separability)
method G5
Ribbon dimensions See 6.4.3 IEC 60794-1-23, method G2 If ribbons are used
and geometry
Ribbon torsion See 6.4.4 IEC 60794-1-23, method G6 If ribbons are used
Ribbon residual See 6.4.5 IEC 60794-1-23, method G8 If ribbons are used
twist
Tube kinking See 6.4.6 IEC 60794-1-23,  If buffer tubes are used
method G7
Bend for optical See 6.4.7 IEC 60794-1-23, method G1
cable elements
Stripping force See 6.4.8 IEC 60794-1-23, method G10A
stability of cabled
optical fibres
Other tests
Fire performance See 6.5.1 IEC 60332-1 (all parts) Regional legal requirements
shall be fulfilled. For more
IEC 60332-3 (all parts)
details, see IEC TR 62222.
IEC 61034 (all parts)
IEC 60754-2
Electrical continuity See 6.5.2 IEC 60794-1-24, method H3 For cables with metallic
elements
Thickness of non- See 6.5.3 IEC 60811-202
metallic sheath
Overall dimensions See 6.5.4 IEC 60811-203

6.2 Mechanical tests
6.2.1 General
The general optical criteria in mechanical tests is no change in attenuation, as described in
IEC 60794-1-1.
– 10 – IEC 60794-6-20:2020 © IEC 2020
In some environmental and installation tests, some increase is accepted.
The number of fibres tested shall be representative of the cable design according to fibre
sampling indicated in IEC 60794-1-1. Different sampling can be agreed between customer and
supplier.
The minimum acceptance criteria for the different designs of cables shall be indicated in the
product specification.
Test methods are defined in the generic specification IEC 60794-1-21, IEC 60794-1-22 and
IEC 60794-1-23. Fire retardant outdoor cables are generally designed according to
IEC 60794-3 with the addition of design characteristics to render them fire retardant to meet
the applicable fire requirements.
6.2.2 Tensile performance
a) Family specifications
While the cable is under short-term tensile load (T , rated tensile load),
M
• the axial fibre strain shall be < 60 % of the fibre proof strain, and
• the attenuation shall be measured and recorded. Any required change in attenuation
shall be agreed between customer and supplier.
While the cable is under the long-term tensile load (TL, residual load),
• The axial fibre strain shall be:
– < 20 % of fibre proof test, for fibre proof tested to ≤ 1 % strain (e.g., 0,69 GPa, 0,2 %
absolute strain), and
– < 17 % of fibre proof test, for fibre proof tested to greater than 1 % to 2 % strain (e.g.,
0,69 GPa to 1,38 GPa, 0,34 % absolute strain for 2 % proof tested fibre)
NOTE For fibres proof tested at levels above 1 % strain, the safe long-term load will not scale linearly
with proof strain, so a lower percentage of the proof stain is applicable. There is no agreement for strain
limits for proof tests above 2 % strain.
• The change in attenuation shall be:
single-mode fibre: no change;
multimode fibre: ≤ 0,2 dB.
Under visual examination without magnification, there shall be no damage to the sheath or
to the cable elements after the test.
b) Test conditions
Method: IEC 60794-1-21, method E1
Length under tension: > 50m
Tensile load on cable: Long-term (T ), short-term (T )
L M
T ≥ 1,5 x W
M
Other loads may be applied in accordance with particular user conditions, e.g. 2 700 N.
T = 0,3 x T
L M
Diameter of test pulleys: Typically 1 m but not less than the minimum loaded bending
diameter specified for the cable
6.2.3 Abrasion
a) Family specifications
Sheath abrasion: There shall be no perforation of the sheath after performing the needle
test according to method E2A of IEC 60794-1-21.
Cable marking abrasion: The print shall be legible after the test performed according to
method E2B of IEC 60794-1-21 (felt test).

b) Test conditions
Method: IEC 60794-1-21, method E2A
Load: 2 N
Number of cycles: 50
Method IEC 60794-1-21, method E2B, method 2
Load: 4 N
Number of cycles: 3
Other loads and number of cycles may be agreed between customer and supplier.
6.2.4 Crush
a) Family specifications
Under the short term load, the attenuation change shall not exceed:
• 0,15 dB for single-mode fibres,
• 0,30 dB for multimode fibres.
At the end of the long term loading, before releasing the load, there shall be no change in
attenuation from the initial value(s).
Under visual examination, there shall be no damage to the sheath or to the cable elements.
The imprint of the plate on the sheath is not considered mechanical damage.
b) Test conditions
Method: IEC 60794-1-21, method E3A
Unarmoured armoured
Short-term load (plate-plate): 1,5 kN 2,2 kN
Long-term load (plate-plate): 0,75 kN  1,1 kN
6.2.5 Impact
a) Family specifications
Under visual examination without magnification, there shall be no damage to the sheath or
to the cable elements. The imprint of the striking surface on the sheath is not considered
mechanical damage.
There shall be no permanent change in attenuation after the test.
b) Test conditions
Method: IEC 60794-1-21, method E4
Number of impacts: One in 3 different places spaced not less than 500 mm apart
Impact energy: 10 J (unarmoured cable), 20 J (armoured cable). Depending on
the cable design, other energies could be selected in agreement
between customer and manufacturer.
Striking surface curvature radius: min. radius 300 mm (flat hammer)
6.2.6 Repeated bending
a) Family specifications
Under visual examination without magnification, there shall be no damage to the sheath and
to the cable elements.
b) Test conditions
Method: IEC 60794-1-21, method E6
Number of cycles: 25 or different number of cycles may be applied in accordance with the
particular user conditions
Load: Adequate to assure uniform contact with the mandrel
Bending radius: 20 d
– 12 – IEC 60794-6-20:2020 © IEC 2020
6.2.7 Torsion
a) Family specifications
Under visual examination without magnification, there shall be no damage to the sheath or
to the cable elements.
b) Test conditions
Method: IEC 60794-1-21, method E7 (as in IEC 60794-3-10:2015, 5.6.2)
Gauge length: 2 m
6.2.8 Bend
a) Family specifications
There shall be no permanent change in attenuation after the test
b) Test conditions
Method: IEC 60794-1-21, method E11
The default method is method E11A.
Diameter of mandrel: 20 d or the minimum bend diameter specified for the cable
Number of cycles: 3
Number of turns/helix: 4
Test temperature: Ambient (unless specifically requested otherwise).
For large and/or stiff cables (e.g. where the mandrel diameter required is > 20 d,
IEC 60794-1-21, method E11B, may be used).
For cable incorporating a non-metallic rod and/or metallic armouring, bending shall be
limited to a value from 20 d to 80 d.
6.2.9 Bending under tension
a) Family specification
Under visual examination without magnification, there shall be no damage to the sheath
and/or to the cable elements.
The permanent increase in attenuation after the test shall be ≤ 0,2 dB for single-mode fibre
and ≤ 0,4 dB for multimode fibre.
b) Test conditions
Method: IEC 60794-1-21, method E18A, procedure 1
Diameter of the mandrel: 40 x d (different diameters could be agreed between the customers
and suppliers)
Tension: ≥ 1,5 x W (short term load T as defined in 6.2.2.
M
Number of moving cycles: 2
6.2.10 Kink
a) Family specification
No kink shall occur at calculated bend diameters greater than the specified minimum.
b) Test conditions
Method: IEC 60794-1-21, method E10
6.2.11 Rip cord functional test
a) Family specification
The rip cord shall rip through the cable sheath and shall not break for the entirety of the pull.
If the rip cord breaks prior to reaching the 1 m mark, two additional follow-up specimens
may be tested from the same cable length. The cable passes if neither of the two follow-up
specimens breaks prior to reaching the 1 m mark.

If the ripcord pulls out of the end of the cable without slitting the sheath, repeat the test.
b) Test conditions
Method: IEC 60794-1-21, method E25
6.3 Environmental tests
6.3.1 Temperature cycling
a) Family specifications
For T to T , there shall be no change in attenuation as defined in IEC 60794-1-1.
A1 B1
b) Test conditions
Method: IEC 60794-1-22, method F1 (T-cycle as indicated in Figure 1 of
IEC 60794-1-1:2017).
Sample length: finished cable length, min. 500 m (fibre length should be longer than 1 000 m)
Table 2 – Low and high temperatures
Low temperature, T High temperature, T Remarks
A1 B1
°C °C
–10 +60
–10 +70
–25 +70
–25 +85
–30 +60
–40 +65
–40 +70 Recommended for FR outdoor cables
–40 +75
–40 +85
The temperature limits in this table are according to the different operating service environments in IEC 61753-1.
A suitable operating service environment should be selected according to the application.

T and T : see Table 2
A1 B1
Alternative high and low temperatures may be agreed between the customer and the
supplier for warmer or colder climates.
Number of cycles: 2, but additional cycles may be required in accordance with particular
customer requirements.
If, due to intended application length, a shorter cable sample is agreed between supplier
and customer, this length shall be sufficient to ensure accurate, repeatable test results as
per the dynamic range and resolution of the optical test equipment.
6.3.2 Water penetration
a) Family specifications
See IEC 60794-3-10:2015, 5.9.1.

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b) Test conditions
Method: IEC 60794-1-22, method F5B or F5C, as applicable
6.3.3 Ageing
a) Family specifications
Calculate the change in attenuation from the initial measurement (see 8.4 of
IEC 60794-1-22:2017, method F9). Unless otherwise agreed between customer and
supplier, the maximum allowable attenuation increase shall be
1) for single-mode fibre, tested at 1 550 nm: 0,25 dB/km, maximum, and 0,10 dB/km,
average, or
2) for multimode fibre, tested at 1 300 nm: 0,6 dB/km, maximum, and 0,4 dB/km, average.
After measuring attenuation, an appropriate section of the cable shall be dissected. Any
elements of the cable which are colour coded (fibres, buffer tubes, sheath) shall be
examined as per Annex A of IEC 60794-1-22:2017.
b) Test conditions
Method: IEC 60794-1-22, method F9
6.3.4 UV resistance
a) Family specifications
After exposure, the average tensile and elongation of the test specimens from the outer
jacket shall be a minimum of 80 % of the original value.
NOTE This test is also needed when only short parts of the cable are installed with exposure to UV irradiation.
Cable jackets of PE-based materials using a minimum of 2,5 % by weight of carbon black
as colourant may be exempt from UV testing per 6.3.4.
b) Test conditions
Method: IEC 60794-1-22, method F14
Use the outdoor, weatherometer test, method ISO 4892-2 (xenon-arc test) for cable testing
Exposure time: 750 h, UV exposure is dependent on the region. Longer exposure times
could be agreed between the customer and supplier
6.3.5 Environmental stress cracking
a) Family specifications
No samples shall be broken after the test.
b) Test conditions
Method: IEC 60811-406 (modifications shall be agreed between the customer and the
manufacturer).
The jacket material is often made of a polymer resin which is highly filled with a flame
retardant additive and thus is more sensitive to stress cracking than the pure polymer (e.g.
PE, PP). Thus, the test shall be adapted to the specific jacket material. Tests shall be agreed
between customer and manufacturer.
6.3.6 Cable external freezing
a) Family specifications
After exposure, there shall be no visible cracks or other openings in the cable sheath. The
maximum increase in attenuation during and after the test shall be as shown in the relevant
detail specification, when frozen and no change after thawing.
b) Test conditions
Method: IEC 60794-1-215, method F15A (test standard to simulate freezing of the medium
surrounding a buried cable as in wet earth or water) or F15B (test standard to simulate
freezing of the medium surrounding an outside cable in a conduit (duct) which is made of
rigid material, e.g. steel), as applicable to the intended installation.

6.3.7 Compound flow
This test is applicable to cables containing thixotropic (grease or gel) filling or flooding
compounds.
a) Family specifications
Unless otherwise specified in the detail specification, the cable specimens shall be permitted
at a maximum flow quantity of 0,050 g. If the flow quantity from one of the cable specimens
exceeds 0,050 g, but is less than 0,100 g, prepare two additional cable specimens in
accordance with IEC 60794-1-22:2017, 15.2 c) (method F16), and test as per
IEC 60794-1-22:2017, 15.4 a) to f) (method F16). The test shall be considered successful if
neither of the second set of specimens has flow quantities which exceed 0,050 g.
b) Test conditions
Method: IEC 60794-1-22, method F16
6.3.8 Bleeding and evaporation
This test is applicable to cables containing thixotropic (grease or gel) filling or flooding
compounds.
a) Family specifications
The reported average results shall not exceed the maximum values given in the detail
specification.
b) Test conditions
Method: IEC 60794-1-23, method G9
6.3.9 Material compatibility
a) Family specifications
Tests according to Table 1 (IEC 60794-1-219 method) should be performed, and the
criteria listed in 3.4.2 (visual inspection) and 3.4.3 (physical testing) of that test method
should be fulfilled.
b) Test conditions
Method: IEC 60794-1-219, method F19
6.4 Cable element tests
6.4.1 Ribbon strippability
a) Family specifications
At least 25 mm of the ribbon matrix and the fibres’ protective coatings shall be removable
with commercially available stripping tools with no fibre breakage. Any remaining coating
residue shall be readily removable using isopropyl alcohol wipes.
b) Test conditions
IEC 60794-1-23, method G10B
6.4.2 Ribbon tear (separability)
a) Family specifications
The primary requirement is to be able to make the tear without fibre damage (coating
damage or fibre breakage). For ribbons where the fibres are required to be separated, the
coloured primary coating of the separated fibre(s) shall be effectively free from ribbon matrix
residues.
____________
Under preparation. Stage at the time of publication: IEC/PCC 60794-1-219:2020.

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Any colour coding of fibres shall remain sufficiently intact within any 25 mm segment to
enable individual fibres to be distinguished from each other, per IEC 60794-1-31:2018,
4.4.2.
The minimum or maximum and mean tear forces shall be as specified in the detail
specification.
b) Test conditions
IEC 60794-1-23, method G5
6.4.3 Ribbon dimensions and geometry
a) Family specifications
Unless otherwise specified in the detail specification, the width, height and fibre alignment
shall be in accordance with IEC 60794-1-31:2018, Table 1.
b) Test conditions
IEC 60794-1-23, method G2
6.4.4 Ribbon torsion
a) Family specifications
The ribbon shall withstand the number of 180° turns until delamination occurs, as given in
the detail specification.
b) Test conditions
Method: IEC 60794-1-23, method G6
6.4.5 Ribbon residual twist
a) Family specifications
The calculated residual twist of optical fibre ribbon shall not exceed the maximum residual
twist requirements of the detail specification. In most cases, a maximum residual twist of
8°/cm is adequate.
b) Test conditions
Method: IEC 60794-1-23, method G8
6.4.6 Tube kinking
a) Family specifications
During the test, no kinking of the sample shall be visible.
b) Test conditions
IEC 60794-1-23, method G7
6.4.7 Bend test for optical cable elements
a) Family specifications
Any increase in attenuation shall comply with the limits shown in the detail specification.
b) Test conditions
Method: IEC 60794-1-23, method G1
6.4.8 Stripping force stability of cabled fibres
a) Family specifications
The change in stripping force shall meet the requirements specified in the detail
specification.
b) Test conditions
Method: IEC 60794-1-23, method G10A

6.5 Other tests
6.5.1 Fire performance
All cables according to this document shall pass fire performance specifications. The
requirements may differ in different regions (e.g. North America, EU). But they also can differ
from country to country.
NOTE 1 IEC TR 62222 provides guidance and recommendations for the requirements and test methods for the fire
performance of communication cables when installed in buildings. The recommendations relate to typical applications
and installation practices, and an assessment of the fire hazards presented. Account is also taken of applicable
legislation and regulation.
IEC TR 62222 references several IEC fire performance test methods and also other test methods that can be required
by local or national legislation and regulation. It is important that the tests to be applied fulfil the national legislation
and regulation and the specific requirements by its intended use.
NOTE 2 Flame retardant cables, including flame retardant outdoor cables for European applications, require CE
marking according to the so-called CPR (construction product regulation, see CLC EN 50575 and subordinate
standards) when permanently installed in buildings. Without the appropriate marking of the product and the supply
of a declaration of performance, the use is not allowed in the European Union.
6.5.2 Electrical continuity of cable metallic elements
a) Family specifications
The metallic elements shall be continuous. The requirement will apply to the elements as a
group or singularly, as specified. If specified, the measured resistance shall be less than
the maximum value.
b) Test conditions
Method: IEC 60794-1-24, method H3
6.5.3 Thickness of non-metallic sheath
a) Family specifications
The cable shall have an overall protective sheath. The cable diameter shall be specified in
the relevant blank detail specification (or product) specification.
b) Test conditions
An appropriate cross-section of the sheath shall be cut, as appropriate. The region of
minimum and/or maximum thickness in the cross-section, as specified, shall be measured.
A measuring microscope or a profile projector of at least 10 x magnification or an optical
digital image analyser shall be used. All these types of equipment shall allow a reading of
0,01 mm and an estimated reading to three decimal places when measuring jacket thickness
with a specified thickness less than 0,5 mm. For sheaths applied over longitudinally irregular
surfaces such as corru
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