FprEN IEC 61300-2-21:2026

• Abstract:

  DOW = DOR + 12 months + DOW

• Status: Not Published
• Publication Date: 06-Dec-2026
• ICS: 33.180.20 - Fibre optic interconnecting devices
• Technical Committee: CLC/TC 86BXA - Fibre optic interconnect, passive and connectorised components
• Drafting Committee: IEC/SC 86B - IEC_SC_86B
• Current Stage: 5020 - Vote circulated - Formal Approval
• Start Date: 24-Jul-2026
• Completion Date: 24-Jul-2026
• Ref Project: kSIST FprEN IEC 61300-2-21:2026 - Fibre optic interconnecting devices and passive components - Basic test and measurement procedures - Part 2-21: Tests - Composite temperature/humidity cyclic test

• Revises: EN 61300-2-21:2010 - Fibre optic interconnecting devices and passive components - Basic test and measurement procedures - Part 2-21: Tests - Composite temperature/humidity cyclic test
• Effective Date: 01-Jun-2021

Overview

FprEN IEC 61300-2-21:2026 is a key international standard developed by CLC and IEC for assessing the environmental durability of fibre optic interconnecting devices and passive components. This standard, titled "Fibre optic interconnecting devices and passive components - Basic test and measurement procedures - Part 2-21: Tests - Composite temperature/humidity cyclic test," establishes a systematic test method to determine how optical devices respond to combined, cyclic temperature and humidity stresses. The test is particularly designed to uncover defects caused by temperature fluctuations, condensation, and freezing, ensuring that fibre optic devices continue to deliver reliable performance even under harsh environmental cycles.

Key Topics

• Composite Temperature/Humidity Cyclic Test: Describes the rigorous process for exposing fibre optic devices to alternating periods of high temperature, high humidity, and cold temperatures over 24-hour cycles.
• Purpose: Evaluates the resistance of fibre optic components to deterioration from thermal cycling, humidity, condensation, and sub-zero temperatures.
• Process Outline:
  • Devices under test (DUT) undergo 10 cycles of 24 hours each, including periods of both high humidity/temperature and cold exposure.
  • The procedure includes preconditioning, initial visual and optical measurements, environmental cycling, interim and final examinations, and reporting.
• Test Environment:
  • Precise control of temperature and humidity chambers, including rapid transitions and maintenance of consistent conditions.
  • Requirements for optical measurement systems adhering to related standards.
• Defect Detection: Focused on identifying deterioration like broken or damaged parts, compromised seals, or changes in attenuation and return loss.

Applications

The composite temperature/humidity cyclic test defined in FprEN IEC 61300-2-21 is essential for:

• Manufacturers:
  • Qualifying fibre optic connectors, adapters, and other passive components for technical and commercial release.
  • Demonstrating compliance with international performance and reliability standards for harsh or rapidly varying environments.
• Telecommunications and Data Centers:
  • Ensuring critical fibre optic infrastructure can withstand real-world environmental challenges, minimizing risk of signal loss or hardware failure.
• Quality Assurance Programs:
  • As part of design validation, ongoing lot testing, or qualification for new suppliers/assemblies.
• Standardized Testing Facilities:
  • Providing certified, repeatable, and comparable results to manufacturers, integrators, and end-users.

Related Standards

To ensure a thorough and harmonized testing regimen, FprEN IEC 61300-2-21 cross-references several key fibre optic standards and supporting documents:

• IEC 60068-2-38: Environmental testing - Composite temperature/humidity cyclic test (basis for the cyclic test procedure).
• IEC 61300-1: General and guidance for test and measurement procedures for fibre optic components.
• IEC 61300-3-1: Visual examinations for fibre optic devices.
• IEC 61300-3-3: Measurement of attenuation and return loss.
• IEC 61753 Series: Performance standards for fibre optic interconnecting devices and passive components.
• IEC 62005 Series: Reliability standards for fibre optic passive components.

These standards help define specific test criteria, measurements, equipment, and reporting protocols, ensuring robust quality and global interoperability in the fibre optics industry.

Practical Value

By following FprEN IEC 61300-2-21, organizations can:

• Verify Product Durability: Assure device longevity and reliability, even in challenging climatic conditions involving rapid humidity and temperature changes.
• Reduce Field Failures: Predict and mitigate issues such as condensation-induced corrosion, mechanical stress from freezing, or humidity-driven material changes.
• Meet Regulatory and Market Expectations: Ensure conformity to widely recognized international benchmarks, facilitating global market access and customer confidence.
• Support Innovation: Provide a baseline for the development of new fibre optic technologies requiring robust environmental resistance.

Leveraging this standard guarantees that fibre optic interconnecting devices and passive components are tested to perform reliably under composite temperature and humidity conditions, supporting the deployment of secure and efficient optical networks worldwide.

SLOVENSKI STANDARD
oSIST prEN IEC 61300-2-21:2025
01-april-2025
Optični spojni elementi in pasivne komponente - Osnovni preskusni in merilni
postopki - 2-21. del: Preskusi - Sestavljeno ciklično preskušanje temperatura-vlaga
Fibre optic interconnecting devices and passive components - Basic test and
measurement procedures - Part 2-21: Tests - Composite temperature/humidity cyclic test
Lichtwellenleiter - Verbindungselemente und passive Bauteile - Grundlegende Prüf- und
Messverfahren - Teil 2-21: Prüfungen - kombinierte Temperatur/Feuchte, zyklisch
Dispositifs d'interconnexion et composants passifs à fibres optiques - Méthodes
fondamentales d'essais et de mesures - Partie 2-21: Essais - Essai cyclique composite
de température et d'humidité
Ta slovenski standard je istoveten z: prEN IEC 61300-2-21:2025
ICS:
33.180.20 Povezovalne naprave za Fibre optic interconnecting
optična vlakna devices
oSIST prEN IEC 61300-2-21:2025 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN IEC 61300-2-21:2025

oSIST prEN IEC 61300-2-21:2025

86B/4988/CDV
COMMITTEE DRAFT FOR VOTE (CDV)
PROJECT NUMBER:
IEC 61300-2-21 ED3
DATE OF CIRCULATION: CLOSING DATE FOR VOTING:
2025-01-31 2025-04-25
SUPERSEDES DOCUMENTS:
86B/4945/CD, 86B/4957A/CC
IEC SC 86B : FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE COMPONENTS
SECRETARIAT: SECRETARY:
Japan Mr Ryo Koyama
OF INTEREST TO THE FOLLOWING COMMITTEES: HORIZONTAL FUNCTION(S):

ASPECTS CONCERNED:
SUBMITTED FOR CENELEC PARALLEL VOTING NOT SUBMITTED FOR CENELEC PARALLEL VOTING
Attention IEC-CENELEC parallel voting
The attention of IEC National Committees, members of
CENELEC, is drawn to the fact that this Committee Draft for
Vote (CDV) is submitted for parallel voting.
The CENELEC members are invited to vote through the
CENELEC online voting system.
This document is still under study and subject to change. It should not be used for reference purposes.
Recipients of this document are invited to submit, with their comments, notification of any relevant patent rights of which
they are aware and to provide supporting documentation.
Recipients of this document are invited to submit, with their comments, notification of any relevant “In Some Countries”
clauses to be included should this proposal proceed. Recipients are reminded that the CDV stage is the final stage for
submitting ISC clauses. (SEE AC/22/2007 OR NEW GUIDANCE DOC).

TITLE:
Fibre optic interconnecting devices and passive components - Basic test and measurement
procedures - Part 2-21: Tests - Composite temperature/humidity cyclic test

PROPOSED STABILITY DATE: 2032
NOTE FROM TC/SC OFFICERS:
electronic file, to make a copy and to print out the content for the sole purpose of preparing National Committee positions.
You may not copy or "mirror" the file or printed version of the document, or any part of it, for any other purpose without
permission in writing from IEC.

oSIST prEN IEC 61300-2-21:2025
IEC CDV 61300-2-21/Ed3 © IEC 2025 2  86B/4988/CDV
1 CONTENTS
2 1 Scope . 5
3 2 Normative references . 5
4 3 Terms and definitions . 6
5 4 General . 6
6 5 Apparatus . 6
7 5.1 General . 6
8 5.2 Chamber for the exposure to high temperature and humidity . 6
9 5.3 Chamber for exposure to cold . 6
10 5.4 Temperature and humidity chamber . 7
11 5.5 Optical measurement equipment . 7
12 6 Procedure . 7
13 6.1 Preparation of DUT . 7
14 6.2 Preconditioning . 7
15 6.3 Initial examinations and measurements . 8
16 6.4 Conditioning . 9
17 6.4.1 General . 9
18 6.4.2 Description of 24 h cycle . 9
19 6.4.2.1 Description of high temperature and humidity subcycle . 9
20 6.4.2.2 Description of cold subcycle . 10
21 6.4.3 Examinations and measurements during test . 12
22 6.5 Recovery . 12
23 6.6 Final examinations and measurements . 12
24 7 Severity. 12
25 8 Details to be specified and reported . 13
27 Figure 1 – Preconditioning:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: 6
28 Figure 2 – Exposure to high temperature and humidity followed by exposure to cold                9
oSIST prEN IEC 61300-2-21:2025
IEC CDV 61300-2-21/Ed3 © IEC 2025 3 86B/4988/CDV
32 INTERNATIONAL ELECTROTECHNICAL COMMISSION
33 ____________
35 FIBRE OPTIC INTERCONNECTING
36 DEVICES AND PASSIVE COMPONENTS –
37 BASIC TEST AND MEASUREMENT PROCEDURES –
39 Part 2-21: Tests –
40 Composite temperature/humidity cyclic test
43 FOREWORD
44 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national
45 electrotechnical committees (IEC National Committees). The object of IEC is to promote international co-operation on all
46 questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, IEC
47 publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and
48 Guides (hereafter referred to as “IEC Publication(s)”). Their preparation is entrusted to technical committees; any IEC National
49 Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-
50 governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely with the
51 International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two
52 organizations.
53 2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international consensus
54 of opinion on the relevant subjects since each technical committee has representation from all interested IEC National
55 Committees.
56 3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in
57 that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC
58 cannot be held responsible for the way in which they are used or for any misinterpretation by any end user.
59 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to
60 the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the
61 corresponding national or regional publication shall be clearly indicated in the latter.
62 5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity assessment
63 services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any services carried out by
64 independent certification bodies.
65 6) All users should ensure that they have the latest edition of this publication.
66 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its
67 technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature
68 whatsoever, whether direct or indirect, or for costs (including legal fees) and expenses arising out of the publication, use of,
69 or reliance upon, this IEC Publication or any other IEC Publications.
70 8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable
71 for the correct application of this publication.
72 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC
73 shall not be held responsible for identifying any or all such patent rights.
74 International Standard IEC 61300-2-21 has been prepared by subcommittee 86B: Fibre optic
75 interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
76 This third edition cancels and replaces the second edition published in 2009. It constitutes a technical
77 revision. The changes with respect to the previous edition are:
78 – to reconsider the whole parts of the standard;
79 – update of Figures 1 and 2 according to IEC 60068-2-38: 2021.
80 The text of this standard is based on the following documents:
FDIS Report on voting
oSIST prEN IEC 61300-2-21:2025
IEC CDV 61300-2-21/Ed3 © IEC 2025 4 86B/4988/CDV
86B/XX/FDIS 86B/XX/RVD
81 This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
82 A list of all the parts of IEC 61300 series, under the general title, Fibre optic interconnecting devices and
83 passive components – Basic test and measurement procedures, can be found on the IEC website.
84 The committee has decided that the contents of this publication will remain unchanged until the stability
85 date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to the specific
86 publication. At this date, the publication will be
87 • reconfirmed,
88 • withdrawn,
89 • replaced by a revised edition, or
90 • amended.
oSIST prEN IEC 61300-2-21:2025
IEC CDV 61300-2-21/Ed3 © IEC 2025 5 86B/4988/CDV
91 FIBRE OPTIC INTERCONNECTING
92 DEVICES AND PASSIVE COMPONENTS –
93 BASIC TEST AND MEASUREMENT PROCEDURES –
95 Part 2-21: Tests –
96 Composite temperature/humidity cyclic test
100 1 Scope
101 The purpose of this part of IEC 61300 is to determine the resistance of a fibre optic device or component
102 to the deteriorative effects of high temperature, humidity and cold conditions.
103 It is intended to reveal defects in a device under test (DUT) caused by breathing as opposed to
104 absorption of moisture. The test covers the effect of the freezing of trapped water in cracks and fissures
105 as well as condensation. However, the degree of condensation will vary depending on the size and
106 thermal mass of the DUT.
107 This test differs from other cyclic damp heat tests in that it derives its increased severity from:
108 a) a greater number of temperature variations leading to pumping actions in a given time;
109 b) a greater cyclic temperature range;
110 c) a higher rate of change of temperature;
111 d) the inclusion of a number of excursions to sub-zero temperature.
112 This type of test is particularly important for fibre optic devices or components made of a variety of
113 different materials.
114 2 Normative references
115 The following referenced documents are indispensable for the application of this document. For dated
116 references, only the edition cited applies. For undated references, the latest edition of the referenced
117 document (including any amendments) applies.
118 IEC 60068-2-38: 2021, Environmental testing – Part 2-38: Tests – Test Z/AD: Composite
119 temperature/humidity cyclic test
120 IEC 61300-1, Fibre optic interconnecting devices and passive components – Basic test and
121 measurement procedures – Part 3-1: Examinations and measurements – Visual examination
122 IEC 61300-3-1, Fibre optic interconnecting devices and passive components – Basic test and
123 measurement procedures – Part 1: General and guidance
124 IEC 61300-3-3
...