IEC 60825-2:2021
(Main)Safety of laser products - Part 2: Safety of optical fibre communication systems (OFCSs)
Safety of laser products - Part 2: Safety of optical fibre communication systems (OFCSs)
IEC 60825-2:2021 provides requirements and specific guidance for the safe operation and maintenance of optical fibre communication systems (OFCSs). In these systems, optical power is possibly accessible outside the confines of the transmitting equipment and/or at great distance from the optical source.
This document requires the assessment of hazard level at each accessible location of the OFCS as a replacement for product classification according to IEC 60825-1. It applies to the installed OFCS as an engineered, end-to-end assembly for the generation, transfer and receipt of optical radiation arising from lasers, light-emitting diodes (LEDs) or optical amplifiers, in which the transference is by means of optical fibre for communication and/or control purposes.
Individual components and subassemblies that fall under the definition of a laser product are subject to the applicable subclause(s) of IEC 60825-1. This document is applicable to individual components and subassemblies intended to be installed within OFCSs.
This document does not apply to optical fibre systems primarily designed to transmit optical power for applications such as material processing or medical treatment.
In addition to the hazards resulting from laser radiation, OFCSs possibly give rise to other hazards, such as fire.
This document does not address safety issues associated with explosion or fire with respect to OFCSs deployed in explosive atmospheres.
This fourth edition cancels and replaces the third edition published in 2004, Amendment 1:2006 and Amendment 2:2010. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition.
a) Recommendations for individual components and subassemblies have been clarified; see Clause 1, paragraph 3.
b) C7 has been revised in accordance with IEC 60825-1:2014, but with an additional limitation related to the skin MPE; see 4.7.2.
c) Condition 2 has been changed, and a detailed description of the measurement and determination method for hazard level has been added; see 4.7.1 and 4.7.2.
d) Annex B has been moved into 4.9. Annex F has been moved forward as Annex B.
e) Clause D.4 Hazard level evaluation examples – Additional examples have been added.
f) Clause D.5 Fault analysis – Explanation and guidance has been simplified.
The contents of the corrigendum of June 2021 have been included in this copy.
Sécurité des appareils à laser - Partie 2: Sécurité des systèmes de télécommunications par fibres optiques (STFO)
IEC 60825-2:2021 fournit des exigences et des conseils spécifiques pour le fonctionnement et l’entretien sécuritaires des systèmes de communication par fibre optique (SCI). Dans ces systèmes, la puissance optique est peut-être accessible en dehors des limites de l’équipement de transmission et/ou à grande distance de la source optique.
Ce document exige l’évaluation du niveau de danger à chaque emplacement accessible de l’OFCS en remplacement de la classification des produits selon l’IEC 60825-1. Elle s’applique à l’OFCS installé en tant qu’assemblage technique de bout en bout pour la génération, le transfert et la réception de rayonnement optique provenant de lasers, de diodes électroluminescentes (LED) ou d’amplificateurs optiques, dans lesquels la transférence se fait au moyen de fibres optiques à des fins de communication et/ou de contrôle.
Les composants et sous-ensembles individuels qui relèvent de la définition d’un produit laser sont assujettis à la sous-demande applicable de l’IEC 60825-1. Ce document s’applique aux composants et sous-ensembles individuels destinés à être installés dans les OFCS.
Ce document ne s’applique pas aux systèmes de fibres optiques principalement conçus pour transmettre de l’énergie optique pour des applications telles que le traitement des matériaux ou le traitement médical.
En plus des dangers résultant du rayonnement laser, les SCI peuvent donner lieu à d’autres dangers, comme le feu.
Le présent document ne aborde pas les questions de sécurité liées aux explosions ou aux incendies en ce qui concerne les SSCI déployés dans des atmosphères explosives.
Cette quatrième édition annule et remplace la troisième édition publiée en 2004, l’amendement 1:2006 et l’amendement 2:2010. Cette édition constitue une révision technique.
Cette édition comprend les changements techniques importants suivants par rapport à l’édition précédente.
a) Les recommandations relatives aux composants et sous-assemblages individuels ont été clarifiées; voir article 1, paragraphe 3.
b) C7 a été révisé conformément à l’IEC 60825-1:2014, mais avec une limitation supplémentaire liée à l’EPM de la peau; voir 4.7.2.
c) L’état 2 a été modifié, et une description détaillée de la méthode de mesure et de détermination du niveau de danger a été ajoutée; voir 4.7.1 et 4.7.2.
d) L’annexe B a été déplacée en 4.9. L’annexe F a été avancée sous le nom d’annexe B.
e) Exemples d’évaluation du niveau de danger de la clause D.4 – D’autres exemples ont été ajoutés.
f) Analyse des défauts de la clause D.5 – L’explication et les directives ont été simplifiées.
Le contenu du corrigendum de juin 2021 a été pris en considération dans cet exemplaire.
General Information
Relations
Overview
IEC 60825-2:2021, published by the International Electrotechnical Commission (IEC), is the fourth edition of the international standard addressing the safety of optical fibre communication systems (OFCSs). This standard presents essential requirements and guidance for the safe operation, maintenance, and hazard assessment of OFCSs where optical power may be accessible outside the transmitting equipment or at distances remote from the optical source.
Replacing product classification methods from IEC 60825-1 with hazard level assessments at each accessible point, IEC 60825-2:2021 applies to end-to-end OFCS installations that transmit optical radiation generated by lasers, LEDs, or optical amplifiers via optical fibres for communication or control purposes.
Key exclusions include fibre systems designed for power transmission in medical or material processing, and safety aspects related to explosive atmospheres. This edition updates the 2004 standard and incorporates significant technical revisions that clarify component recommendations, hazard evaluation methods, and organizational safety practices.
Key Topics
Hazard Level Assessment:
The standard requires detailed evaluation of the optical hazard level at all accessible locations in an OFCS instead of only classifying the product. This method enhances safety by addressing real-world exposure scenarios.Protective Measures and Marking:
Specific guidelines for protective housing, cable connectors, and labelling ensure effective hazard communication in unrestricted, restricted, and controlled locations. Labels must be durable and provide warnings for invisible laser radiation.Automatic Power Reduction (APR):
IEC 60825-2:2021 details the use of APR mechanisms that reduce emitted power to lower hazard levels automatically, including provisions for manual restart scenarios and disabling APR under controlled conditions.Organizational Requirements:
This standard outlines responsibilities for manufacturers, installers, service providers, and operating organizations. It emphasizes proper training, fault analysis, and maintenance procedures for ensuring ongoing safety.Safety Control by Location Type:
The system classifies areas as unrestricted, restricted, or controlled, prescribing specific hazard level requirements and safety measures tailored to each location type.Fault Analysis and Risk Management:
Annexes offer guidance on fault analysis, including failure mode and effect analysis (FMEA), and hazard evaluation examples that help organizations identify and mitigate risks effectively.
Applications
IEC 60825-2:2021 is critical for industries and sectors utilizing optical fibre communication technologies where laser or LED sources send information or control signals. Key applications include:
Telecommunications:
Ensuring safety in fibre optic networks that support modern communication infrastructure, including passive optical networks (PONs) and high-speed data links.Industrial Control Systems:
Protecting maintenance personnel working with fibre-based control links in manufacturing and process automation environments.Data Centers and IT Infrastructure:
Managing laser safety risks associated with optical transceivers and fibre cabling used extensively in data centers.Safety and Maintenance Operations:
Establishing safe working practices and maintenance procedures to reduce exposure to hazardous optical radiation during installation, repair, and servicing activities.
Related Standards
IEC 60825-1:
This is the foundational standard for the safety of laser products, classifying laser devices by hazard class. IEC 60825-2:2021 complements this by focusing on hazard levels in optical fibre systems rather than individual products.IEC 61300 Series:
Addresses fibre optic interconnecting devices and passive components, which relate to the design and connectors discussed in IEC 60825-2.ISO/IEC 24702:
Provides generic cabling guidelines for industrial premises and may be referenced for structured installation practices.IEC 62471:
Photobiological safety of lamps and lamp systems, relevant when assessing radiation emissions and human exposure.
By following IEC 60825-2:2021, manufacturers, installers, and operators of optical fibre communication systems can minimize risks from laser radiation and related hazards, ensuring compliance with internationally recognized safety practices while maintaining efficient communication networks. This standard remains indispensable for promoting user safety and harmonizing safety engineering in fiber optic technology worldwide.
Frequently Asked Questions
IEC 60825-2:2021 is a standard published by the International Electrotechnical Commission (IEC). Its full title is "Safety of laser products - Part 2: Safety of optical fibre communication systems (OFCSs)". This standard covers: IEC 60825-2:2021 provides requirements and specific guidance for the safe operation and maintenance of optical fibre communication systems (OFCSs). In these systems, optical power is possibly accessible outside the confines of the transmitting equipment and/or at great distance from the optical source. This document requires the assessment of hazard level at each accessible location of the OFCS as a replacement for product classification according to IEC 60825-1. It applies to the installed OFCS as an engineered, end-to-end assembly for the generation, transfer and receipt of optical radiation arising from lasers, light-emitting diodes (LEDs) or optical amplifiers, in which the transference is by means of optical fibre for communication and/or control purposes. Individual components and subassemblies that fall under the definition of a laser product are subject to the applicable subclause(s) of IEC 60825-1. This document is applicable to individual components and subassemblies intended to be installed within OFCSs. This document does not apply to optical fibre systems primarily designed to transmit optical power for applications such as material processing or medical treatment. In addition to the hazards resulting from laser radiation, OFCSs possibly give rise to other hazards, such as fire. This document does not address safety issues associated with explosion or fire with respect to OFCSs deployed in explosive atmospheres. This fourth edition cancels and replaces the third edition published in 2004, Amendment 1:2006 and Amendment 2:2010. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition. a) Recommendations for individual components and subassemblies have been clarified; see Clause 1, paragraph 3. b) C7 has been revised in accordance with IEC 60825-1:2014, but with an additional limitation related to the skin MPE; see 4.7.2. c) Condition 2 has been changed, and a detailed description of the measurement and determination method for hazard level has been added; see 4.7.1 and 4.7.2. d) Annex B has been moved into 4.9. Annex F has been moved forward as Annex B. e) Clause D.4 Hazard level evaluation examples – Additional examples have been added. f) Clause D.5 Fault analysis – Explanation and guidance has been simplified. The contents of the corrigendum of June 2021 have been included in this copy.
IEC 60825-2:2021 provides requirements and specific guidance for the safe operation and maintenance of optical fibre communication systems (OFCSs). In these systems, optical power is possibly accessible outside the confines of the transmitting equipment and/or at great distance from the optical source. This document requires the assessment of hazard level at each accessible location of the OFCS as a replacement for product classification according to IEC 60825-1. It applies to the installed OFCS as an engineered, end-to-end assembly for the generation, transfer and receipt of optical radiation arising from lasers, light-emitting diodes (LEDs) or optical amplifiers, in which the transference is by means of optical fibre for communication and/or control purposes. Individual components and subassemblies that fall under the definition of a laser product are subject to the applicable subclause(s) of IEC 60825-1. This document is applicable to individual components and subassemblies intended to be installed within OFCSs. This document does not apply to optical fibre systems primarily designed to transmit optical power for applications such as material processing or medical treatment. In addition to the hazards resulting from laser radiation, OFCSs possibly give rise to other hazards, such as fire. This document does not address safety issues associated with explosion or fire with respect to OFCSs deployed in explosive atmospheres. This fourth edition cancels and replaces the third edition published in 2004, Amendment 1:2006 and Amendment 2:2010. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition. a) Recommendations for individual components and subassemblies have been clarified; see Clause 1, paragraph 3. b) C7 has been revised in accordance with IEC 60825-1:2014, but with an additional limitation related to the skin MPE; see 4.7.2. c) Condition 2 has been changed, and a detailed description of the measurement and determination method for hazard level has been added; see 4.7.1 and 4.7.2. d) Annex B has been moved into 4.9. Annex F has been moved forward as Annex B. e) Clause D.4 Hazard level evaluation examples – Additional examples have been added. f) Clause D.5 Fault analysis – Explanation and guidance has been simplified. The contents of the corrigendum of June 2021 have been included in this copy.
IEC 60825-2:2021 is classified under the following ICS (International Classification for Standards) categories: 31.260 - Optoelectronics. Laser equipment; 33.180.01 - Fibre optic systems in general. The ICS classification helps identify the subject area and facilitates finding related standards.
IEC 60825-2:2021 has the following relationships with other standards: It is inter standard links to IEC 60825-2:2021/COR1:2021, IEC 60825-2:2004/AMD1:2006, IEC 60825-2:2004/AMD2:2010, IEC 60825-2:2004, IEC 60825-2:2004/ISH2:2018, IEC 60825-2:2004/ISH1:2008. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
You can purchase IEC 60825-2:2021 directly from iTeh Standards. The document is available in PDF format and is delivered instantly after payment. Add the standard to your cart and complete the secure checkout process. iTeh Standards is an authorized distributor of IEC standards.
Standards Content (Sample)
IEC 60825-2 ®
Edition 4.0 2021-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Safety of laser products –
Part 2: Safety of optical fibre communication systems (OFCSs)
Sécurité des appareils à laser –
Partie 2: Sécurité des systèmes de télécommunications par fibres optiques
(STFO)
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IEC 60825-2 ®
Edition 4.0 2021-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Safety of laser products –
Part 2: Safety of optical fibre communication systems (OFCSs)
Sécurité des appareils à laser –
Partie 2: Sécurité des systèmes de télécommunications par fibres optiques
(STFO)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.260; 33.180.01 ISBN 978-2-8322-9366-9
– 2 – IEC 60825-2:2021 © IEC 2021
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms and definitions . 8
4 Requirements . 12
4.1 General . 12
4.2 Protective housing of OFCS . 12
4.3 Fibre cables . 13
4.4 Cable connectors . 13
4.4.1 General . 13
4.4.2 Unrestricted locations . 13
4.4.3 Restricted locations . 13
4.4.4 Controlled locations . 13
4.5 Labelling and marking . 14
4.5.1 General requirements . 14
4.5.2 Marking of connectors of optical transmitters and optical amplifiers . 17
4.5.3 Markings for groups of connectors . 18
4.5.4 Durability – Indelibility requirements for safety markings . 18
4.5.5 Warning for invisible radiation . 18
4.6 Organizational requirements . 18
4.6.1 Manufacturers of ready-to-use OFCSs or turnkey systems . 18
4.6.2 Installation and service organization . 19
4.6.3 Operating organization . 19
4.7 Assessment of hazard level . 20
4.7.1 Determination of hazard level and the use of Condition 2 . 20
4.7.2 Hazard level assignment of OFCS . 20
4.7.3 Additional requirements applicable to all hazard levels . 22
4.7.4 Requirements for transient accessible exposures when using APR . 23
4.7.5 Conditions for tests and assessment . 23
4.8 Automatic power reduction (APR) . 24
4.8.1 General . 24
4.8.2 Automatic restart . 24
4.8.3 Manual restart with assured continuity . 24
4.8.4 Manual restart without assured continuity . 24
4.8.5 Disabling of the APR . 24
4.9 Hazard level requirements by location type . 25
4.9.1 General . 25
4.9.2 Unrestricted locations . 25
4.9.3 Restricted locations . 25
4.9.4 Controlled locations . 26
Annex A (informative) Rationale . 27
Annex B (informative) Clarification of the meaning of "hazard level". 28
B.1 General . 28
B.2 Class . 28
B.3 Hazard level . 28
B.4 Rationale to 4.7 . 28
B.5 Rationale to Clause D.5 . 29
Annex C (informative) Methods of hazard/safety analysis . 30
Annex D (informative) Application notes for the safe use of OFCS . 31
D.1 Overview. 31
D.2 Areas of application . 31
D.2.1 Typical OFCS installations . 31
D.2.2 Typical system components . 32
D.2.3 Typical operating functions . 33
D.3 OFCS power limits . 33
D.4 Hazard level evaluation examples . 35
D.4.1 Single wavelength over the same fibre . 35
D.4.2 Multiple wavelengths over the same fibre . 41
D.4.3 Bi-directional (full duplex) transmission. 43
D.4.4 Automatic power reduction . 43
D.4.5 Multiple fibres . 45
D.4.6 Ribbon cable . 45
D.4.7 Power diminution due to power splitters and fibre losses . 47
D.4.8 General considerations and examples . 47
D.5 Fault analysis – Explanation and guidance . 48
D.5.1 General . 48
D.5.2 Commonly used fault analysis techniques . 48
D.5.3 Failure modes, effects, and criticality analysis . 48
D.5.4 Consequence analysis . 48
D.6 Suggested working practices . 50
D.6.1 General working practices . 50
D.6.2 Live working practices for hazard levels 1, 1M, 2, 2M and 3R . 51
D.6.3 Working practices for hazard level 3B . 51
D.6.4 Formal power-down and power-up procedure for hazard level 3B . 51
D.7 Maximum output power during shutdown . 52
Annex E (informative) Guidance for service and maintenance . 54
E.1 Tests and measurements . 54
E.2 Safety precautions . 54
E.2.1 General remarks . 54
E.2.2 Precautions in locations with hazard levels 1M, 2M, 3R and 3B . 55
E.2.3 Training programme . 55
Bibliography . 56
Figure D.1 – PON (passive optical network)-based system . 47
Table 1 – Marking in unrestricted locations . 15
Table 2 – Marking in restricted locations . 16
Table 3 – Marking in controlled locations . 17
Table 4 – Measurement aperture diameters and distances for the default (simplified)
evaluation . 20
Table 5 – Summary of requirements for location types in OFCS . 26
Table D.1 – OFCS power limits for 11 µm mode field diameter (MFD) single-mode (SM)
fibres and 0,18 numerical aperture multimode (MM) fibres (core diameter 50 µm) . 34
– 4 – IEC 60825-2:2021 © IEC 2021
Table D.2 – Relation between the number of fibres in a ribbon fibre and the maximum
permitted power (example) . 46
Table D.3 – Examples of power limits for optical fibre communication systems having
automatic power reduction to reduce emissions to a lower hazard level . 53
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY OF LASER PRODUCTS –
Part 2: Safety of optical fibre communication systems (OFCSs)
FOREWORD
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International Standard IEC 60825-2 has been prepared by IEC technical committee 76: Optical
radiation safety and laser equipment.
This fourth edition cancels and replaces the third edition published in 2004, Amendment 1:2006
and Amendment 2:2010. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition.
a) Recommendations for individual components and subassemblies have been clarified; see
Clause 1, paragraph 3.
b) C has been revised in accordance with IEC 60825-1:2014, but with an additional limitation
related to the skin MPE; see 4.7.2.
c) Condition 2 has been changed, and a detailed description of the measurement and
determination method for hazard level has been added; see 4.7.1 and 4.7.2.
d) Annex B has been moved into 4.9. Annex F has been moved forward as Annex B.
e) Clause D.4 Hazard level evaluation examples – Additional examples have been added.
f) Clause D.5 Fault analysis – Explanation and guidance has been simplified.
– 6 – IEC 60825-2:2021 © IEC 2021
The text of this International Standard is based on the following documents:
FDIS Report on voting
76/670/FDIS 76/674/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 60825 series, published under the general title Safety of laser
products, 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.
INTRODUCTION
The objective of this document is to:
– protect people from optical radiation emitted by OFCSs;
– provide requirements for manufacturers, installation organizations, service organizations
and operating organizations in order to establish procedures and supply information so that
proper precautions can be adopted;
– ensure adequate warnings are provided to individuals regarding the potential hazards
associated with OFCSs through the use of signs, labels and instructions.
Annex A gives a more detailed rationale for this document.
The safety of an OFCS depends to a significant degree on the characteristics of the equipment
forming that system. Depending on the characteristics of the equipment, relevant safety
information needs to be marked on the product or included within the instructions for use.
Where required by the level of potential hazard, the installation organization or end-user /
operating organization or both are responsible for the safe deployment and use of OFCSs.
The installation organization and service organization are responsible for adherence to safety
instructions during installation and service operations, respectively. The end-user or operating
organization is responsible for adherence to safety instructions during operation and
maintenance functions.
It is recognized that the user of this document can fall into one or more of the aforementioned
categories of manufacturer, installation organization, end-user or operating organization.
– 8 – IEC 60825-2:2021 © IEC 2021
SAFETY OF LASER PRODUCTS –
Part 2: Safety of optical fibre communication systems (OFCSs)
1 Scope
This document provides requirements and specific guidance for the safe operation and
maintenance of optical fibre communication systems (OFCSs). In these systems, optical power
is possibly accessible outside the confines of the transmitting equipment and/or at great
distance from the optical source.
This document requires the assessment of hazard level at each accessible location of the OFCS
as a replacement for product classification according to IEC 60825-1. It applies to the installed
OFCS as an engineered, end-to-end assembly for the generation, transfer and receipt of optical
radiation arising from lasers, light-emitting diodes (LEDs) or optical amplifiers, in which the
transference is by means of optical fibre for communication and/or control purposes.
NOTE 1 Throughout this document, a reference to 'laser' is taken to include LEDs and optical amplifiers.
Individual components and subassemblies that fall under the definition of a laser product are
subject to the applicable subclause(s) of IEC 60825-1. This document is applicable to individual
components and subassemblies intended to be installed within OFCSs.
This document does not apply to optical fibre systems primarily designed to transmit optical
power for applications such as material processing or medical treatment.
In addition to the hazards resulting from laser radiation, OFCSs possibly give rise to other
hazards, such as fire.
This document does not address safety issues associated with explosion or fire with respect to
OFCSs deployed in explosive atmospheres.
NOTE 2 The hazard presented by optical radiation emerging from a fibre is determined by the wavelength and
power emerging from the fibre and also by the optical characteristics of the fibre itself (see Annex A).
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 60825-1:2014, Safety of laser products – Part 1: Equipment classification and requirements
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60825-1 and the
following 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
3.1
accessible location
part or location within an OFCS at which, under reasonably foreseeable events, human access
to laser radiation is possible without the use of a tool
3.2
automatic power reduction
APR
feature of an OFCS whereby the accessible power is reliably reduced to a specified level within
a specified time, whenever there is an event which could result in human exposure to radiation
Note 1 to entry: The term "automatic power reduction" (APR) used in this document encompasses the following
terms used in ITU-T Recommendation G.664 [1]:
– automatic laser shutdown (ALS);
– automatic power reduction (APR);
– automatic power shutdown (APSD).
Note 2 to entry: The term automatic laser shut off (ALSO) has also been used by some manufacturers in the industry.
Note 3 to entry: A fibre-cable break is an example of an event which could result in human exposure to radiation.
3.3
end-user
person or organization using the OFCS in the manner the system was designed to be used
Note 1 to entry: The end-user cannot necessarily control the power generated and transmitted within the system.
Note 2 to entry: If the person or organization is using the OFCS for a communications application in a manner other
than as designed by the manufacturer, then that person/organization assumes the responsibilities defined in this
document applicable to a manufacturer or installation organization.
3.4
hazard level
level of potential hazard at any accessible location within an OFCS
Note 1 to entry: It is based on the level of laser radiation which could become accessible in a reasonably
foreseeable event, e.g. a fibre cable break. It is closely related to the laser classification procedure defined in 5.3 in
IEC 60825-1:2014. The meaning of hazard level is clarified in Annex B.
3.5
hazard level 1
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 1 as defined
in 4.7.2 a) and 4.7.3, will not exceed the accessible emission limits of Class 1 in IEC 60825-1
for the applicable wavelength and emission duration, with additional constraints as defined in
4.7.2 a)
Note 1 to entry: "Additional constraints" refers to additional and stricter constraints that 4.7.2 a) of this document
places on the values specified in IEC 60825-1:2014 for the accessible emission limits of Class 1 in the wavelength
range 1 200 nm to 1 400 nm.
– 10 – IEC 60825-2:2021 © IEC 2021
3.6
hazard level 1M
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 1M as defined
in 4.7.2 a) and 4.7.3, will not exceed the accessible emission limits of Class 1 in IEC 60825-1
for the applicable wavelength and emission duration, with additional constraints as defined in
4.7.2 a)
Note 1 to entry: "Additional constraints" refers to additional and stricter constraints that 4.7.2 a) of this document
places on the values specified in IEC 60825-1:2014 for the accessible emission limits of Class 1 in the wavelength
range 1 200 nm to 1 400 nm.
3.7
hazard level 2
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 2 as defined
in 4.7.2 b) and 4.7.3, will not exceed the accessible emission limits of Class 2 in IEC 60825-1
for the applicable wavelength and emission duration
3.8
hazard level 2M
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 2M as defined
in 4.7.2 b) and 4.7.3, will not exceed the accessible emission limits of Class 2 in IEC 60825-1
for the applicable wavelength and emission duration
3.9
hazard level 3R
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 3R as defined
in 4.7.2 c) and 4.7.3, will not exceed the accessible emission limits of Class 3R in IEC 60825-
1 for the applicable wavelength and emission duration, with additional constraints as defined in
4.7.2 c)
Note 1 to entry: "Additional constraints" refers to additional and stricter constraints that 4.7.2 c) of this document
places on the values specified in IEC 60825-1:2014 for the accessible emission limits of Class 3R in the wavelength
range 1 200 nm to 1 400 nm.
3.10
hazard level 3B
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 3B as defined
in 4.7.2 d) and 4.7.3, will not exceed the accessible emission limits of Class 3B in IEC 60825-
1 for the applicable wavelength and emission duration
3.11
hazard level 4
hazard level at which, under a reasonably foreseeable event, human access to laser radiation
(accessible emission), evaluated by the measurement conditions for hazard level 4 as defined
in 4.7.2 e) and 4.7.3, will exceed the accessible emission limits of Class 3B in IEC 60825-1 for
the applicable wavelength and emission duration
Note 1 to entry: This document is applicable for the operation and maintenance of OFCS. In order to achieve an
adequate level of safety for persons who might come into contact with the optical transmission path, hazard level 4
is not permitted within this document. It is permitted to use protection systems, such as automatic power reduction,
to achieve the required hazard level where the transmitted power under normal operating conditions (e.g. no fault
exists in the fibre path) exceeds that permitted for a particular location type. For instance, it is possible for accessible
parts of an OFCS to be hazard level 1 even though the power transmitted down the fibre under normal operating
conditions is Class 4.
3.12
installation organization
organization or individual that is responsible for the installation of an OFCS
3.13
controlled location
location with controlled access
accessible location where an engineering or administrative control is present to make it
inaccessible, except to authorized personnel with appropriate laser safety training
Note 1 to entry: For examples, see D.2.1 a).
3.14
restricted location
location with restricted access
accessible location that is normally inaccessible by the general public by means of any
administrative or engineering control measure, but that is accessible to authorized personnel
who might not have laser safety training
Note 1 to entry: For examples, see D.2.1 b).
3.15
unrestricted location
location with unrestricted access
accessible location where there are no measures restricting access to members of the general
public
Note 1 to entry: For examples, see D.2.1 c).
3.16
manufacturer
organization or individual that constructs or modifies OFCSs by assembling or incorporating
optical devices and other components
Note 1 to entry: Typical components in OFCSs are shown in D.2.2.
3.17
operating organization
organization or individual that is responsible for the operation of an OFCS
3.18
optical fibre communication system
OFCS
engineered, end-to-end assembly for the generation, transfer and reception of optical radiation
arising from lasers, LEDs or optical amplifiers, in which the transference is by means of optical
fibre for communication and/or control purposes
3.19
reasonably foreseeable event
event whose occurrence under given circumstances can be predicted fairly accurately, and the
occurrence probability or frequency of which is not low or very low
Note 1 to entry: Examples of reasonably foreseeable events might include the following: fibre cable break, optical
connector disconnection, operator error or inattention to safe working practices.
Note 2 to entry: Any intentional act to create a hazard is not considered as a reasonably foreseeable event.
3.20
service organization
organization or individual that is responsible for the servicing of an OFCS
– 12 – IEC 60825-2:2021 © IEC 2021
3.21
subassembly
discrete unit, subsystem, network element, or module of an OFCS which contains an optical
emitter or optical amplifier
Note 1 to entry: The definition of subassembly is different from that of optical sub-assembly defined in
IEC TS 62538 [2].
4 Requirements
4.1 General
Clause 0 defines the restrictions that are to be placed on an OFCS and on the location types in
which an OFCS can operate, in accordance with the hazard that arises from optical radiation
becoming accessible as a result of a reasonably foreseeable event, such as an open connector
or fibre break, etc. Whenever one or more alterations are made to an OFCS, the organization
responsible for such alteration(s) shall determine whether each alteration could affect the
originally assigned hazard level. If the originally assigned hazard level has changed, the
organization responsible for the alteration(s) shall, if necessary, re-label those locations in the
system that are accessible so as to ensure continued compliance with this document.
Each accessible location within an OFCS shall be separately assessed to determine the hazard
level at that location. Where multiple communications systems are present at a location, the
hazard level for the location shall be evaluated by the following methods depending on the types
of the fibre cables.
a) For a conventional loose tube fibre optic cable without ribbon fibre structures, the radiation
shall be assessed individually from each of the fibres in a cable, and the maximum radiation
from one fibre shall be used as the basis for the hazard level evaluation.
b) For a ribbon fibre optic cable, the cumulative radiation from one flat ribbon fibre shall be
assessed as either an extended source or a point source, as appropriate.
It is noted that there is no need to perform the complete evaluation for extended sources if the
simplified point source analysis for the ribbon fibres results in a hazard level acceptable to the
operating organization. Additionally, in order to perform the extended source analysis, it is
necessary to know the radiation from each individual fibre in the ribbon. If this information is
not available then a point source analysis using C = 1 is applied.
Based on the determined hazard level, appropriate actions shall be taken to ensure compliance
with this document. These actions could for example involve restriction of access to the location,
or the implementation of additional safety features or redesign of the optical communications
system to reduce the hazard level.
Visual observation of fibre tips using magnifying optics should be avoided in situations where
there is potential for optical emission from the fibre.
Electric power transmitting cables comprising OFCSs with optical fibre cables defined in the
IEC 60794-4 series [3] shall meet the requirements of any applicable electrical standard
besides this document.
4.2 Protective housing of OFCS
Each OFCS shall have a protective housing which, when in place, prevents human access to
laser radiation in excess of hazard level 1 limits under normal operating conditions.
___________
Numbers in square brackets refer to the Bibliography.
4.3 Fibre cables
For all hazard levels, the fibre optic cable shall have mechanical properties appropriate to its
physical location. Cables for various physical locations are described in the IEC 60794-2 series
[4], IEC 60794-3 series [5] and IEC 60794-4 series [3]. Where necessary, additional protection,
for example ducting, conduit or raceway, might be required for locations where the fibre would
otherwise be susceptible to damage. Even if the potential hazard at any accessible location
within an OFCS is the lowest hazard level, the mechanical properties need to be considered as
optical power in fibre cable can exceed the MPE.
4.4 Cable connectors
4.4.1 General
The following requirements for cable connectors can be achieved by the mechanical design of
the connectors, or by the positioning of the connector, or by any other suitable means.
Whichever means is chosen, human access to radiation above that permitted for connectors in
a particular location type shall be prevented.
Hazard level is required to be assigned more strictly for connectors than that for fibre cables.
For example in an unrestricted location, accessible radiation level is allowed up to hazard level
1M for cables whereas the accessible radiation from an optical connector is limited to hazard
level 1.
NOTE The use of a tool for disconnection is one example of a mechanical solution.
4.4.2 Unrestricted locations
In unrestricted locations,
– if the accessible radiation level exceeds hazard level 2 within the wavelength range 400 nm
to 700 nm, then suitable means shall limit access to the radiation exceeding hazard level 2
from the connector,
– if the accessible radiation level exceeds hazard level 1 in all other cases, then suitable
means shall limit access to the radiation exceeding hazard level 1 from the connector.
NOTE In an unrestricted location the highest hazard levels are hazard level 2M for the wavelength range 400 nm
to 700 nm and hazard level 1M in all other cases (see 4.9.2).
4.4.3 Restricted locations
In restricted locations,
– if the accessible radiation level exceeds hazard level 2M within the wavelength range
400 nm to 700 nm, then suitable means shall limit access to the radiation exceeding hazard
level 2M from the connector,
– if the accessible radiation level exceeds hazard level 1M in all other cases, then suitable
means shall limit access to the radiation exceeding hazard level 1M from the connector.
NOTE In a restricted location the highest hazard level is hazard level 1M, 2M or 3R, whichever is the higher (see
4.9.3).
4.4.4 Controlled locations
In controlled locations,
– if the accessible radiation level exceeds hazard level 2M within the wavelength range
400 nm to 700 nm, then suitable means shall limit access to the radiation exceeding hazard
level 2M from the connector,
– if the accessible radiation level exceeds hazard level 1M in all other cases, then suitable
means shall limit access to the radiation exceeding hazard level 1M from the connector.
NOTE In a controlled location the highest hazard level is hazard level 3B (see 4.9.4).
– 14 – IEC 60825-2:2021 © IEC 2021
4.5 Labelling and marking
4.5.1 General requirements
Where required by 4.5, each optical connector, splice box or other part emitting radiation when
opened, shall be marked (e.g. with a label, sleeve, tag, tape, etc.), if the hazard level at the
location is in excess of hazard level 1. The information shall consist of the information identified
in Table 1, Table 2 or Table 3, as applicable.
Where the accessible radiation at points of disconnection is hazard level 1 or hazard level 1M,
it is permitted for the above information to be provided in information for the user instead of as
a marking on the product.
Labelling of hazard level 1M is permitted but not mandatory since it is only in restricted or
controlled locations that the connector outputs assigned as hazard level 1M are allowed and
only appropriately trained technical staff are allowed to work in such locations.
Markings shall be coloured black on a yellow background. Labels reproduced in the
documentation provided by the manufacturer or by the operating organization are permitted to
be black on a white background.
It is acceptable to reduce the marking in size, provided that the result is legible. All hazard level
labelling is the responsibility of the installation organization or end-user / operating organization,
including the labelling of subassemblies containing lasers or optical amplifiers. This is because
hazard level is a feature of the (end-to-end) OFCS, and might therefore depend on system wide
features such as APR, etc.
Except for the case of subassemblies used for stand-alone applications, each optical connector,
splice box or other part that is intended to permit access to optical radiation when opened shall
be marked (e.g. with a label, sleeve, tag, tape, etc.) in accordance with Table 1, Table 2 or
Table 3, as applicable.
Subassemblies used for stand-alone applications shall be allocated a class and marked
according to IEC 60825-1.
Subassemblies that are installed as part of an OFCS shall be allocated a hazard level and
marked according to this document.
Table 1 – Marking in unrestricted locations
Accessible Required marking – Unrestricted location
hazard
level
1 No marking required
a
1M
No marking required
2M
3R Not permitted
3B Not permitted
NOTE See 4.5.5 regarding invisible laser beam hazards.
a
4.4.2 requires access to radiation from a connector to be limited to hazard level 1 by suitable means, and the
mechanical design of the fibre cables is consistent with the relevant parts of IEC 60794 [3], [4], [5] (see 4.3) .
Therefore, hazard level 1M
...
IEC 60825-2:2021 is a crucial standard that ensures the safety of optical fibre communication systems (OFCSs), primarily addressing the hazards associated with laser products and optical devices. The scope of this standard is particularly important as it shifts the focus from traditional product classification under IEC 60825-1 to a more nuanced assessment of hazard levels at each accessible location within OFCSs. This approach emphasizes a comprehensive understanding of safety, recognizing that optical power may be accessible outside the confines of transmitting equipment or at distances from the optical source. One of the notable strengths of IEC 60825-2:2021 is its detailed guidance on the operation and maintenance of OFCSs, providing clarity on safety measures for components and subassemblies defined as laser products. By addressing individual components within the system, this standard enhances the safety framework for OFCS installation and usage, ensuring that potential hazards are systematically evaluated and managed. The technical updates incorporated into this fourth edition signal a significant advancement over the previous version. Key revisions include enhanced clarity in recommendations for components, a thorough examination of hazard level determination methods, and an expansion of examples related to hazard level evaluation. Additionally, the simplification of guidance related to fault analysis reflects an effort to make the standard more accessible and user-friendly for practitioners. The relevance of IEC 60825-2:2021 cannot be overstated, as it addresses not only hazards from laser radiation but also additional risks such as fire, although it does not cover safety concerns in explosive atmospheres. This dual focus on multiple hazard types broadens the scope of safety considerations for OFCSs, making it an essential resource for those involved in the design, installation, and maintenance of optical fibre communication systems. Overall, IEC 60825-2:2021 stands out as a vital standard that effectively combines rigorous safety requirements with practical guidance, ensuring that optical fibre communication systems operate safely within the evolving technological landscape. The clear delineation of responsibilities for both operators and manufacturers aids in fostering a safer environment in environments where optical radiation is utilized.
IEC 60825-2:2021は、光ファイバー通信システム（OFCSs）の安全性に関する標準として、非常に重要な役割を果たしています。この標準は、光学放射を生成、転送、受信するためのエンドツーエンドのアセンブリとして設計されたOFCSsの安全な運用とメンテナンスに関する要求事項と具体的な指針を提供しています。特に、光学パワーが送信機器の境界外でアクセス可能な場合や光源から大きな距離にある場合の危険レベルの評価が重要であり、IEC 60825-1に基づく製品分類を置き換えるものです。 この標準は、OFCS内に設置されることを意図した個々のコンポーネントおよびサブアセンブリにも適用されますが、主に材料加工や医療治療の用途のために設計された光ファイバーシステムには適用されません。この点は、特定の用途に特化したシステムの安全性を管理する上で非常に重要です。 IEC 60825-2:2021の強みは、光関連の危険に加えて、火災などの他の危険をも考慮している点にあります。また、この改訂版は、第三版からの技術的な変更が多く含まれており、推奨事項が明確にされたり、危険レベルの測定方法が詳細に説明されたりするなど、利用者向けに非常に参考になる情報が盛り込まれています。 特に、IEC 60825-1との整合性を図るために、C7条が改訂されており、皮膚の最大許容曝露（MPE）に関連する制限が追加されています。また、危険レベル評価のための具体的な例や故障分析に関するガイダンスが簡素化されている点も見逃せません。 全体として、IEC 60825-2:2021は、光ファイバー通信システムの安全性を確保するための最新の技術情報を提供し、産業界での適切な理解と実施を促進するものです。この文書の適用は、光通信技術の発展に伴い、ますます重要性を増しています。
IEC 60825-2:2021은 광섬유 통신 시스템(OFCS)의 안전성을 보장하기 위한 요구사항과 특정 지침을 제공합니다. 이 표준은 발신 장비의 경계를 넘거나 광원에서 멀리 떨어진 장소에서 광학 전력을 접근할 수 있는 가능성을 고려합니다. OFCS의 각 접근 가능한 위치에서 위험 수준을 평가하도록 요구하며, 이는 IEC 60825-1에 따른 제품 분류의 대체가 됩니다. 이 표준은 레이저, 발광 다이오드(LED), 광 증폭기에서 발생하는 광복사의 생성, 전달 및 수신을 위한 엔지니어링된 종단간 조립체로 설치된 OFCS에 적용됩니다. 이 문서는 레이저 제품 정의에 해당하는 개별 구성 요소 및 하위 조립체에도 적용되며, OFCS 내부에 설치될 목적의 구성 요소에 대한 부분 조항을 따릅니다. 그러나 의료 치료나 소재 가공 등과 같은 용도로 광학 전력을 전송하기 위해 주로 설계된 광섬유 시스템에는 적용되지 않습니다. 또한, 레이저 방사선으로 인한 위험 외에도, OFCS는 화재와 같은 다른 위험을 발생시킬 수 있음을 제시합니다. 폭발성 환경에서 배치된 OFCS와 관련된 폭발 또는 화재의 안전 문제는 다루지 않습니다. 이번 제4판은 2004년에 발표된 제3판, 수정판 1(2006) 및 수정판 2(2010)를 대체하며, 기술적으로 수정된 내용을 포함합니다. 주요 기술 변경 사항으로는, 개별 구성 요소 및 하위 조립체에 대한 권장 사항이 명확해졌고(제1조, 3항 참조), C7이 IEC 60825-1:2014에 따라 수정되었지만 피부 MPE와 관련된 추가 제한이 포함되었습니다(4.7.2 참조). 조건 2가 변경되었고, 위험 수준 측정 및 결정 방법에 대한 상세 설명이 추가되었습니다(4.7.1 및 4.7.2 참조). 부록 B는 4.9로 이동하고, 부록 F는 부록 B로 앞으로 이동되었습니다. D.4 위험 수준 평가 예제에는 추가 예제가 포함되었고, D.5 고장 분석에 대한 설명과 지침이 단순화되었습니다. 2021년 6월의 정오표 내용도 이 사본에 포함되어 있습니다. IEC 60825-2:2021은 OFCS의 안전성을 보장하는 데 필수적인 표준으로, 관련 산업에 중요한 기여를 할 것입니다.
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