kSIST FprEN IEC 61300-2-21:2026

• Abstract:

  DOW = DOR + 12 months + DOW

• Status: Not Published
• Public Enquiry End Date: 24-Apr-2025
• ICS: 33.180.20 - Fibre optic interconnecting devices
• Technical Committee: MOC - Mobile Communications
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 28-Jul-2026
• Due Date: 15-Sep-2026
• Ref Project: 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: SIST 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 (IEC 61300-2-21:2009)
• Effective Date: 01-Jun-2021

Overview

kSIST FprEN IEC 61300-2-21:2026 specifies the composite temperature/humidity cyclic test for fibre optic interconnecting devices and passive components. Developed by the Slovenian Institute for Standardization (SIST) and in alignment with the IEC 61300 series, this standard details a rigorous procedure to evaluate the durability and reliability of fibre optic devices under environmental stress. By subjecting devices to repeated temperature and humidity cycles, the test aims to reveal weaknesses such as material incompatibilities, manufacturing flaws, or design defects that may affect long-term performance in demanding operating environments.

Keywords: Fibre optic devices, temperature humidity test, cyclic test, environmental testing, reliability, IEC 61300, SIST standard, passive components

Key Topics

• Purpose and Scope:
  The standard prescribes a method to determine the resistance of fibre optic components to deteriorative effects from alternating high temperature, high humidity, and cold exposures. Its focus is on identifying failures due to "breathing" (moisture ingress and freeze-thaw cycles) rather than absorption, with specific attention to condensation, freezing of trapped moisture, and pumping actions from temperature fluctuations.

• Test Procedure Highlights:

  • Devices Under Test (DUT) are subjected to 10 cycles, each lasting 24 hours.
  • Each cycle includes phases of high temperature and humidity, followed by sub-zero exposures in selected cycles.
  • Measurements of optical performance (attenuation, return loss) are required before, during, and after testing.
  • The procedure identifies physical failures such as cracked casings, broken seals, or deformed parts as well as performance degradation.

• Test Equipment and Conditions:

  • Environmental chambers capable of precision temperature and humidity control.
  • Optical measurement equipment as per IEC 61300-3-3.
  • Strict procedures for DUT preparation (including preconditioning and thermal stabilization).

• Severity and Reporting:

  • Conditions such as temperature range, humidity levels, and cycle duration can be adjusted per relevant specifications.
  • Full documentation of test parameters, measurement results, and any deviations from procedures is mandatory for test reports.

Applications

Implementing the composite temperature/humidity cyclic test according to IEC 61300-2-21 is critical for:

• Product Qualification:
  Manufacturers use these tests to ensure that fibre optic connectors, couplers, adapters, and other passive components can withstand environmental extremes, such as those encountered in telecommunication infrastructure, data centers, military, and industrial settings.

• Quality Assurance and Reliability Engineering:
  The procedure helps identify design or material weaknesses that could lead to premature failure, supporting continuous improvement and robust product development.

• Compliance and Procurement:
  Customers and regulators may require evidence that fibre optic products conform to IEC 61300-2-21 as a condition for acceptance or certification, making adherence to this standard crucial for market access.

• Failure Analysis:
  When issues arise in the field, replicating the composite temperature/humidity cycles provides insights into failure mechanisms linked to moisture ingress, material compatibility, or inadequate sealing.

Related Standards

• IEC 60068-2-38: Environmental testing – Composite temperature/humidity cyclic test (basis for the prescribed test method).
• IEC 61300-1: General and guidance on test procedures for fibre optic devices.
• IEC 61300-3-1: Visual examination requirements.
• IEC 61300-3-3: Methods for active monitoring of optical performance during testing.
• IEC 61753 Series: Performance standards for fibre optic interconnecting devices.
• IEC 62005 Series: Reliability standards for fibre optic components.

Adhering to kSIST FprEN IEC 61300-2-21:2026 ensures that fibre optic interconnects and passive components are reliably qualified for use in environments subject to significant temperature and humidity fluctuations, supporting robust and long-lasting fibre optic network infrastructure.

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:
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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
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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
...