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

Status
Published
Publication Date
15-Mar-2021
Current Stage
PPUB - Publication issued
Completion Date
16-Mar-2021
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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)

IEC 60825-2:2021-03(en-fr)

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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




Warning! Make sure that you obtained this publication from an authorized distributor.

Attention! Veuillez vous assurer que vous avez obtenu cette publication via un distributeur agréé.

® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

---------------------- Page: 3 ----------------------
– 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

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IEC 60825-2:2021 © IEC 2021 – 3 –
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

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– 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

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IEC 60825-2:2021 © IEC 2021 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________

SAFETY OF LASER PRODUCTS –

Part 2: Safety of optical fibre communication systems (OFCSs)

FOREWORD
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rights. IEC shall not be held responsible for identifying any or all such patent rights.
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
7
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.

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– 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.

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IEC 60825-2:2021 © IEC 2021 – 7 –
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.

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– 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.

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IEC 60825-2:2021 © IEC 2021 – 9 –
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.

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– 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
...

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