IEC 60875-1:2024

IEC 60875-1 ®
Edition 7.0 2024-04
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre optic interconnecting devices and passive components – Non-wavelength-
selective fibre optic branching devices –
Part 1: Generic specification
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IEC 60875-1 ®
Edition 7.0 2024-04
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre optic interconnecting devices and passive components – Non-wavelength-
selective fibre optic branching devices –
Part 1: Generic specification
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.20 ISBN 978-2-8322-8768-2

– 2 – IEC 60875-1:2024 RLV © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
3.1 Basic terms and definitions . 7
3.2 Component definitions . 8
3.3 Performance parameter definitions . 9
4 Requirement . 10
4.1 Classification . 10
4.1.1 General . 10
4.1.2 Types . 11
4.1.3 Style . 11
4.1.4 Variant .
4.1.5 Normative reference extensions.
4.2 Documentation . 13
4.2.1 Symbols . 13
4.2.2 Specification system .
4.2.2 Drawings . 14
4.2.3 Measurements . 15
4.2.4 Test data sheets . 15
4.2.5 Instructions for use . 15
4.3 Standardization system of performance standards . 15
4.3.1 Interface standards .
4.3.2 Performance standards .
4.3.3 Reliability standards .
4.3.4 Interlinking .
4.4 Design and construction . 18
4.4.1 Materials . 18
4.4.2 Workmanship . 19
4.5 Quality . 19
4.6 Performance requirements . 19
4.7 Identification and marking . 19
4.7.1 General . 19
4.7.2 Variant identification number .
4.7.2 Component marking . 19
4.7.3 Package marking . 20
4.8 Safety . 20
Annex A (informative) Examples technologies of non-wavelength-selective fibre optic
branching devices . 21
Annex B (informative) Examples of fabrication technology of PLC chips . 23
Bibliography . 25

Figure 1 – Non-wavelength-selective branching device .
Figure 2 – Non-wavelength-selective branching device .
Figure 3 – Non-wavelength-selective branching device .
Figure 4 – Non-wavelength-selective branching device .

Figure 5 – Standards .
Figure A.1 – FBT-type optical branching device technology . 21
Figure A.2 – PLC-type optical branching device technology . 22
Figure B.1 – Fabrication by FHD method . 23
Figure B.2 – Fabrication by CVD method . 24
Figure B.3 – Fabrication by ion-exchange method . 24

Table 1 – Three-level IEC specification structure .
Table 2 – Standards interlink matrix .
Table 3 – Quality assurance options .

– 4 – IEC 60875-1:2024 RLV © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COMPONENTS – NON-WAVELENGTH-SELECTIVE
FIBRE OPTIC BRANCHING DEVICES –

Part 1: Generic specification
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
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
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) 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
may be required to implement this document. However, implementers are cautioned that this may not represent
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 60875-1:2015. 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 60875-1 has been prepared by IEC technical committee 86B: Fibre optic interconnecting
devices and passive components. It is an International Standard.
This seventh edition cancels and replaces the sixth edition published in 2015. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) removal of variant and reference extensions in clause classification
b) removal of specification system in clause documentation
c) removal of interface standards, reliability standards and interlinking in clause
standardization system
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/4868/FDIS 86B/4903/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 60875 series, published under the general title Fibre optic
interconnecting and passive components – Non-wavelength-selective fibre optic branching
devices, 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.
IMPORTANT – The "colour inside" logo on the cover page of this document 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 60875-1:2024 RLV © IEC 2024
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COMPONENTS – NON-WAVELENGTH-SELECTIVE
FIBRE OPTIC BRANCHING DEVICES –

Part 1: Generic specification
1 Scope
This part of IEC 60875 applies to non-wavelength-selective fibre optic branching devices, all
exhibiting the following features:
– they are passive, in that they contain no optoelectronic or other transducing elements;
– they have three or more ports for either the entry or exit, or both, of optical power, and share
optical power among these ports in a predetermined fashion;
– the ports are optical fibres, or optical fibre connectors.
This document establishes uniform requirements for the optical, mechanical and environmental
properties.
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 60027 (all parts), Letter symbols to be used in electrical technology
IEC 60050 (all parts), International Electrotechnical Vocabulary (available at
http://www.electropedia.org/)
IEC 60050-731, International Electrotechnical Vocabulary – Chapter 731: Optical fibre
communication
IEC 60617 (all parts), Graphical symbols for diagrams
IEC 60695-11-5, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method –
Apparatus, confirmatory test arrangement and guidance
IEC 60825 (all parts), Safety of laser products
IEC 61300 (all parts), Fibre optic interconnecting devices and passive components – Basic test
and measurement procedures
IEC 61754 (all parts), Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces
IEC TR 61930, Fibre optic graphic symbology
IEC TS 62627-09, Fibre optic interconnecting devices and passive components – Vocabulary
for passive optical devices
ISO 129-1, Technical drawings product documentation (TPD) – Indication Presentation of
dimensions and tolerances – Part 1: General principles
ISO 286-1, Geometrical product specifications (GPS) – ISO code system for tolerances on
linear sizes – Part 1: Basis of tolerances, deviations and fits
ISO 1101, Geometrical product specifications (GPS) – Geometrical tolerancing – Tolerances of
form, orientation, location and run-out
ISO 8601, Data elements and interchange formats – Information interchange – Representation
of dates and times
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-731 and
IEC TS 62627-09 and the following apply.
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 Basic terms and definitions
3.1.1
port
optical fibre or optical connector attached to a passive component for the entry (input port)
and/or exit (output port) of the optical power
3.1.1
optical pigtail
short length of jumper fibre or cable terminated with or without a connector at the end forming
an optical port for an optical component
3.1.3
transfer matrix
optical properties of a non-wavelength-selective optic branching device can be defined in terms
of an n × n matrix of coefficients, n being the number of ports, with the coefficients representing
the fractional optical power transferred between designated ports
Note 1 to entry: In general, the transfer matrix T is as follows:
t t ⋅ ⋅ ⋅ t 
11 12 1n
 
t
 
⋅
 
T =
 
⋅ t
ij
 
⋅
 
t t
 n1 nn 
 
where
t is the ratio of the optical power P transferred out of port j with respect to input power P into port i, that is:
i
ij ij
t = P /P
i
ij ij
– 8 – IEC 60875-1:2024 RLV © IEC 2024
The transfer matrix is used to classify the different types of non-wavelength-selective branching devices which are
specified in this generic specification.
Note 2 to entry: In a non-wavelength-selective branching device, the coefficients t may be a function of the input
ij
wavelength, input polarization or modal power distribution. The values of these parameters are provided in the detail
specification, when necessary.
Note 3 to entry: Single-mode, non-wavelength-selective branching devices may operate in a coherent fashion with
respect to multiple inputs. Consequently, the transfer coefficients may be affected by the relative phase and intensity
of simultaneous coherent optical power inputs at two or more ports.
3.1.4
transfer coefficient
element t of the transfer matrix
ij
3.1.5
conducting port pair
two ports i and j between which t is nominally greater than zero
ij
3.1.6
isolated port pair
two ports i and j between which t is nominally zero, and a is nominally infinite
ij ij
3.2 Component definitions
3.2.1
non-wavelength-selective branching device
coupler
splitter
bidirectional passive component possessing three or more ports which operates non-selectively
over a specified range of wavelengths, divides or combines optical power coming into one or
more input port(s) among its one or more output port(s) in a predetermined fashion, without any
amplification, switching, or other active modulation
3.2.2
bidirectional non-wavelength-selective branching device
device whose transfer matrix element of t is equal to t for all i and j
ij ji
3.2.3
non-bidirectional non-wavelength-selective branching device
device which at least one transfer matrix element of t is not equal to t
ij ji
3.2.4
balanced coupler
non-wavelength-selective branching device designed and intended to produce to ensure that
the power at each output port power from the same input port is equal
3.2.5
unbalanced coupler
non-wavelength-selective branching device designed and intended to produce to ensure that
the power at least one each output port power from the same input port is not equal
3.2.6
tap-coupler
unbalanced coupler
Note 1 to entry: Typically the coupling ratio is from 1 % to 20 %.

3.3 Performance parameter definitions
3.3.1
insertion loss
reduction in optical power between an input and output port of a passive component expressed
in decibels and defined as
a = –10 log (P /P )
1 0
where
P is the optical power launched into the input port;
P is the optical power received from the output port.
3.3.2
return loss
fraction of input power that is returned from a port of a passive component expressed in
decibelsand defined as
RL = –10 log (P /P )
r 0
where
P is the optical power launched into a port;
P is the optical power received back from the same port.
r
3.3.3
directivity
optical attenuation expressed in decibels between ports which have conducting connections at
any state within isolated port pairs
Note 1 to entry: It is a positive value expressed in dB. Generally, directivity for a passive device is defined as the
minimum value of directivities of all ports.
Note 2 to entry: Directivity is the optical loss between ports which has no conducting connections within all operating
wavelength ranges.
Note 3 to entry: Directivity is defined for port pairs which are expected to be isolated but not expressly intended to
be isolated. That means it is expected to isolate leak light and/or stray light.
3.3.4
excess loss
total power lost in a non-wavelength-selective branching device when an optical signal is
launched into port i, defined as

EL = −10 log10 t
i ij
∑
j
where the summation is performed only over those values j for which i and j are conducting
ports
Note 1 to entry: For a non-wavelength-selective branching device with n input ports, there is an array of n values
of excess loss, one for each input port i.
3.3.1
uniformity
U
difference between the maximum and minimum attenuation measured for all output ports for
one input port
– 10 – IEC 60875-1:2024 RLV © IEC 2024
Note 1 to entry: For each input port, it is the maximum value over the operating wavelength range or ranges. The
uniformity for a device with more than one input port is defined as the maximum value of uniformities of all input
ports.
Note 2 to entry: Uniformity is expressed as difference of maximum and minimum value of each attenuation (insertion
loss) from a common input port. It is expressed in decibels.
Note 3 to entry: Generally, uniformity for a passive device is defined as maximum value of uniformities of all ports.
3.3.2
coupling ratio
splitting ratio
CR
for a given input port i, the ratio of light at a given output port k to the total light from all output
ports where j represents the operational output ports
Note 1 to entry: Coupling ratio is calculated by
CR = t t
ik ik ∑ ij
j
where t is a transmission element from port i to port j.
ij
3.3.7
operating wavelength
nominal wavelength λ, at which a passive component is designed to operate with the specified
performance
3.3.8
operating wavelength range
specified range of wavelengths from λ to λ about a nominal operating wavelength λ ,
i min i max i
within which a passive component is designed to operate with the specified performance
Note 1 to entry: For a non-wavelength-selective branching device with more than one operating wavelength, the
corresponding wavelength ranges are not necessarily equal.
3.3.9
polarization dependent loss
PDL
maximum variation of insertion loss due to a variation of the state of polarization (SOP) over all
the SOPs
Note 1 to entry: This note applies to the French language only.
Note 2 to entry: This note applies to the French language only.
4 Requirement
4.1 Classification
4.1.1 General
Several technologies exist for the manufacturing of non-wavelength-selective branching
devices. Typical technologies of non-wavelength selective branching devices are:
– Fused biconic taper;
– Planar lightwave circuit.
Some examples are given in Annex A.
Non-wavelength-selective branching devices shall be classified as follows:

– type;
– style;
– variant;
– performance standard grade;
– assessment level;
– normative reference extensions.
4.1.2 Types
The main characteristics of each type are as follows:
– transmissive or;
– reflective;.
– bidirectional or unidirectional;
– tree or star;
– any combination of the above.
4.1.3 Style
4.1.3.1 General
Non-wavelength-selective branching devices may be classified into styles based on the fibre
type(s), the connector type(s), the cable type(s), the housing shape, and the configuration. The
configuration of branching device ports are classified as follows:
4.1.3.2 Configuration A
Device containing integral fibre optic pigtails, without connectors (see Figure 1).
EXAMPLE
IEC
Figure 1 – Non-wavelength-selective branching device
4.1.3.3 Configuration B
Device containing integral fibre optic pigtails, with a connector on each pigtail (see Figure 2).
EXAMPLE
IEC
Figure 2 – Non-wavelength-selective branching device
4.1.3.4 Configuration C
Device containing fibre optic connectors as an integral part of the device housing (see Figure 3).

– 12 – IEC 60875-1:2024 RLV © IEC 2024
EXAMPLE
IEC
Figure 3 – Non-wavelength-selective branching device
4.1.3.5 Configuration D
Device containing some combination of the interfacing features of the preceding configurations
(see Figure 4).
EXAMPLE
IEC
Figure 4 – Non-wavelength-selective branching device
4.1.4 Variant
The branching device variant identifies those common features which encompass structurally
similar components.
Examples of features which define a variant include, but are not limited to the following:
– orientation of ports;
– means of mounting.
4.1.5 Normative reference extensions
Normative reference extensions are used to identify the integration of independent standards
specifications or other reference documents into blank detail specifications.
Unless otherwise specified, additional requirements imposed by an extension are mandatory.
Usage is primarily intended to merge associated components to form hybrid devices or
integrated functional application requirements that are dependent on technical expertise used
for other than fibre optics.
Published reference documents produced by ITU, consistent with the scope of the relevant IEC
specification series may be used as extension.
Some optical splice configurations require special qualification provisions which shall not be
imposed universally. This accommodates individual component design configurations,
specialized field tooling or specific application processes. In this case, requirements necessary
to assure repeatable performance or adequate safety, and provide additional guidance for
complete product specification. These extensions are mandatory whenever used to prepare,
assemble or install an optical splice either for field application usage or preparation of
qualification test specimens. The relevant specification shall clarify all stipulations. However,
design and style dependent extensions shall not be imposed universally.
In the event of conflicting requirements, precedence, in descending order, shall be generic over
mandatory extension, over blank detail, over detail, over application specific extension.

Non-wavelength-selective branching devices may have fibre or cable type pigtails with or
without optical connectors. If equipped with optical connectors, the optical connectors shall
meet the requirements of IEC 61754 series.
4.2 Documentation
4.2.1 Symbols
Graphical and letter symbols shall should, whenever possible, be taken from IEC 60027 series,
IEC 60617 series and IEC TR 61930.
4.2.2 Specification system
4.2.2.1 General
This specification is part of a three-level IEC specification system. Subsidiary specifications
shall consist of blank detail specifications and detail specifications. This system is shown in
Table 1. There are no sectional specifications for non-wavelength-selective branching devices.
Table 1 – Three-level IEC specification structure
Specification Examples of information to be included Applicable to
level
Basic Assessment system rules Two or more component families or sub-
families
Inspection rules
Optical measuring methods
Environmental test methods
Sampling plans
Identification rule
Marking standards
Dimensional standards
Terminology standards
Symbol standards
Preferred number series
SI units
Generic Specific terminology Component family
Specific symbols
Specific units
Preferred values
Marking
Quality assessment procedures
Selection of tests
Qualification approval and/or
capability approval procedures
Blank detail Quality conformance test schedule Groups of types having a common test
schedule
Inspection requirements
Information common to a number of types
Detail Individual values Individual type
Specific information
Completed quality conformance test
schedules
– 14 – IEC 60875-1:2024 RLV © IEC 2024
4.2.2.2 Blank detail specifications
Blank detail specifications are not, by themselves, a specification level. They are associated
with the generic specification.
Each blank detail specification shall be limited to one environmental category.
Each blank detail specification shall contain:
– minimum mandatory test schedules and performance requirements;
– one or more assessment levels;
– the preferred format for stating the required information in the detail specification;
– in case of hybrid components, including connectors, addition of appropriate entry fields to
show the reference normative document, document title and issue date.
4.2.2.3 Detail specifications
A specific non-wavelength-selective branching device is described by a corresponding detail
specification, which is prepared by filling in the blanks of the blank detail specification. Within
the constraints imposed by this generic specification, the blank detail specification may be filled
in by any national committee of the IEC, thereby defining a particular non-wavelength-selective
branching device design as an IEC standard.
Detail specifications shall specify the following, as applicable:
– type (see 4.1.2);
– style (see 4.1.3);
– variant(s) (see 4.1.4);
– part identification number for each variant (see 4.7.2);
– drawings, dimensions required (see 4.2.3);
– performance requirements (see 4.6).
4.2.2 Drawings
4.2.2.1 General
The drawings and dimensions given in detail specifications shall not restrict themselves to
details of construction, nor shall they be used as manufacturing drawings.
4.2.2.2 Projection system
Either first angle or third angle projection shall be used for the drawings in documents covered
by this specification. All drawings within a document shall use the same projection system and
the drawings shall state which system is used.
4.2.2.3 Dimensional system
All dimensions shall be given in accordance with ISO 129-1, ISO 286-1 and ISO 1101.
The metric system shall be used in all specifications.
Dimensions shall not contain more than five significant digits.
When units are converted, a note shall be added in each relevant specification and the
conversion between systems of units shall use a factor of 25,4 mm to 1 inch.

4.2.3 Measurements
4.2.3.1 Measurement method
The measurement method for optical, mechanical, climatic, and environmental characteristics
of branching devices to be used shall should be defined and selected preferentially from the
IEC 61300 series.
The size measurement method to be used shall be specified in the detail specification for any
dimensions which are specified within a total tolerance zone of ≤0,01 mm.
4.2.3.2 Reference components
Reference components for measurement purposes, if required, shall be specified in the relevant
IEC standards or industrial specifications.
4.2.4.3 Gauges
Gauges, if required, shall be specified in the relevant specification.
4.2.4 Test data sheets
Test data sheets shall be prepared for each test conducted as required by a relevant IEC
standard or industrial specification. The data sheets shall be included in the qualification report
and in the periodic inspection report.
Data sheets shall contain the following information as a minimum:
– title of test and date;
– specimen description including the type of fibre and the variant identification number
(see 4.7.2);
– test equipment used and date of latest calibration;
– all applicable test details;
– all measurement values and observations;
– sufficiently detailed documentation to provide traceable information for failure analysis.
4.2.5 Instructions for use
Instructions for use, when required, shall be given by the manufacturer and shall include:
– assembly and connection instructions;
– cleaning method;
– safety aspects;
– additional information as necessary.
4.3 Standardization system of performance standards
4.3.1 Interface standards
The interface standards provide both manufacturer and user with all the information they require
to make or use a product conforming to the physical features of that standard interface.
Interface standards fully define and provide dimensions for the features essential for the mating
and unmating of optical connectors and other components. They also serve to position the
optical datum target, where defined, relative to other reference datum.
Interface standards ensure that connectors and adaptors that comply with the standard will fit
together. The standards may also contain tolerance grades for ferrules and alignment devices.
Tolerance grades are used to provide different levels of alignment precision.

– 16 – IEC 60875-1:2024 RLV © IEC 2024
The interface dimensions may also be used to design other components that will mate with the
connectors. For example, an active device mount can be designed using the adapter interface
dimensions. The use of these dimensions combined with those of a standard plug, provides the
designer with assurance that the standard plugs will fit into the optical device mount. They also
provide the location of the plug's optical datum target.
Standard interface dimensions do not, by themselves, guarantee optical performance. They
guarantee connector mating at a specified fit. Optical performance is currently guaranteed via
the manufacturing specification. Products from the same or different manufacturing
specifications using the same standard interface will always fit together. Guaranteed
performance can be given by any single manufacturer only for products delivered to the same
manufacturing specification. However, it can be reasonably expected that some level of
performance will be obtained from products having different manufacturing specifications,
although the level of performance cannot be expected to be any better than that of the lowest
specified performance.
4.3.2 Performance standards
Performance standards contain a series of tests and measurements (which may or may not can
be grouped into a specified schedule depending on the requirements of that standard) with
clearly defined conditions, severities and pass/fail criteria. The tests are intended to be run on
a "once-off" basis to prove any product's ability to satisfy the "performance standards"
requirements of a market sector, user group or system location. A product that has been shown
to meet all the requirements of a performance standard can be declared as complying with a
performance standard but should then be controlled by a quality assurance/ or quality
conformance programme.
A key point of the test and measurement standards for their application (particularly with regard
to attenuation (insertion loss) and return loss) in conjunction with the interface standards of
interproduct compatibility can be defined. Conformity of each individual product to this
document will be ensured.
4.3.3 Reliability standards
Reliability standards are intended to ensure that a component can meet performance
specifications under stated conditions for a stated time period.
For each type of component, the following shall be identified (and shall appear in the standard):
– failure modes (observable, general mechanical or optical effects of failure);
– failure mechanisms (general causes of failure common to several components);
– failure effects (detailed cause of failure, specific to component).
These are all related to environmental and material aspects.
Initially, just after component manufacture, there is an "infant mortality phase" during which
many components would fail if deployed in the field. To avoid early field failure, all components
can be subjected to a screening process in the factory, involving environmental stress that may
be mechanical, thermal or humidity related. This is to induce known failure mechanisms in a
controlled environmental situation to occur earlier than would normally be seen in an
unscreened population. For those components that survive (and are then sold), there is a
reduced failure rate since these mechanisms have been eliminated.
Screening is an optional part of the manufacturing process rather than a test method. It does
not affect the "useful life" of a component, defined as the period during which it performs
according to specifications. Eventually, other failure mechanisms appear and the failure rate
increases beyond the defined threshold. At this point, the useful life ends and the "wear-out
period" begins and the component must be replaced.

At the beginning of useful life, performance testing on a sampled population of components may
be applied by the supplier, by the manufacturer or by a third party. This is to ensure that the
component meets performance specifications over the range of intended environments at this
initial time. Reliability testing, on the other hand, is applied to ensure that the component meets
performance specifications for at least a specified minimum useful lifetime or for a specified
maximum failure rate. These tests are usually carried out by utilizing the performance testing
but increasing duration and severity in order to accelerate the failure mechanism.
A reliability theory relates component reliability testing to component parameters and to lifetime
or failure rate under testing. The theory then extrapolates these to life or failure rate under less
stressful service conditions. The reliability specifications include values of the component
parameters needed to ensure the specified minimum lifetime or maximum failure rate in service.
4.3.4 Interlinking
Standards currently under preparation are given in Figure 5. A large number of the test and
measurement standards exist already and the quality assurance qualification approval
standards have existed for many years.
When interface, performance and reliability standards are in place, the matrix given in Table 2
demonstrates some of the options available for product standardization.
Product A is a product that is fully IEC standardized, having a standard interface and meeting
defined performance standards and reliability standards.
Product B is a product with a proprietary interface, but which meets a defined IEC performance
standard and reliability standard.
Product C is a product which complies with an IEC standard interface but does not meet the
requirement of either an IEC performance standard or reliability standard.
Product D is a product which complies with an IEC interface standard and with a performance
standard, but does not meet a reliability requirement.
Obviously, the matrix is more complex than shown since there will be a number of interface,
performance and reliability standards that can be cross-related. In addition, all the products
may be subject to a recognized quality assurance programme or even a national or company
quality assurance system. Table 3 shows options of qualification approval, capability approval
and technology approval within a quality assurance programme.

– 18 – IEC 60875-1:2024 RLV © IEC 2024
Test and
Interface Performance Reliability Quality
measurement
IEC 61753-XX IEC 62005-XX
IEC 61300-XX
IEC 61754-XX
(IEC 60068-ZZ)
IEC
specification
structure
–------------------
Generic
specification
Sectional
specification
Blank detail
specification
Detail
specifcation
IEC
Figure 5 – Standards
Table 2 – Standards interlink matrix
Interface standard Performance standard Reliability standard
Product A Yes Yes Yes
Product B No Yes Yes
Product C Yes No No
Product D Yes Yes No
Table 3 – Quality assurance options
Company A Company B Company C
a b c a b c a b c
QA CA TA QA CA TA QA CA TA
Product A x  x   x
Product B x  x  x
Product C x  x  x
Product D x   x  x
a
Qualification approval
b
Capability approval
c
Technology approval
4.4 Design and construction
4.4.1 Materials
4.4.1.1 Corrosion resistance
All materials used in the construction shall be corrosion resistant or suitably finished to meet
the requirements of the relevant IEC standard or industrial specification.

4.4.1.2 Non-flammable materials
When non-flammable materials are required, the requirement shall be sp
...