GB/T 3836.22-2023Explosive atmospheres - Part 22: Protection of equipment and transmission system using optical radiation (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents" Drafting:

This document is Part 22 of GB (/T) 3836 "Explosive Environments": GB (/T)3836 has released the following parts:

---Part 1: General requirements for equipment;

---Part 2: Equipment protected by flameproof enclosure "d";

---Part 3: Equipment protected by increased safety type "e";

---Part 4: Equipment protected by intrinsically safe "i";

---Part 5: Equipment protected by positive pressure enclosure "p";

---Part 6: Equipment protected by liquid immersion type "o";

---Part 7: Equipment protected by sand-filled mold "q";

---Part 8: Equipment protected by type "n";

---Part 9: Equipment protected by casting type "m";

---Part 11: Test methods and data for classification of gas and vapor material properties;

---Part 12: Test methods for characteristics of combustible dust substances;

---Part 13: Repair, overhaul, restoration and modification of equipment;

---Part 14: Place classification for explosive gas environments;

---Part 15: Design, selection and installation of electrical devices;

---Part 16: Inspection and maintenance of electrical installations;

---Part 17: Equipment protected by positive pressure rooms "p" and artificial ventilation rooms "v";

---Part 18: Intrinsically safe electrical systems;

---Part 20: Equipment with an equipment protection level (EPL) of Ga level;

---Part 21: Application of production quality management system for explosion-proof products;

---Part 22: Protection measures for optical radiation equipment and transmission systems;

---Part 23: Class I EPLMa level equipment for use in gas and/or coal dust environments;

---Part 24: Equipment protected by special type "s";

---Part 25: Process sealing requirements between flammable process fluids and electrical systems;

---Part 26: Guidelines for Static Electricity Hazards;

---Part 27: Static electricity hazard test;

---Part 28: Basic methods and requirements for non-electrical equipment for explosive atmospheres;

---Part 29: Structural safety type "c" of non-electrical equipment for explosive atmospheres, controlled ignition source type "b", liquid immersion type "k";

---Part 30: Equipment and components for explosive environments in underground mines;

---Part 31: Equipment protected by dust ignition resistant enclosure "t";

---Part 32: Electronically controlled spark time limit intrinsically safe systems;

---Part 33: Equipment for severe working conditions;

---Part 34: Complete sets of equipment;

---Part 35: Classification of explosive dust environment locations;

---Part 36: Electrical safety devices to control potential ignition sources of explosion-proof equipment:

This document replaces GB/T 3836.22-2017 "Explosive environments Part 22: Protective measures for optical radiation equipment and transmission systems", Compared with GB/T 3836.22-2017, in addition to structural adjustments and editorial changes, the main technical changes are as follows:

---Changed the scope of the file (see Chapter 1, Chapter 1 of the:2017 edition);

---Changed the general requirements for optical radiation equipment (see Chapter 4, Chapter 4 of the:2017 edition);

---Changed the requirements for explosion-proof types of optical radiation equipment (see Chapter 5, Chapter 5 of the:2017 edition);

---Changed the requirements for type inspection and testing (see Chapter 6, Chapter 6 of the:2017 edition);

---Changed the marking requirements (see Chapter 7, Chapter 7 of the:2017 edition);

---Changed the ignition risk assessment (see Appendix C, Appendix C of the:2017 version):

This document is modified to adopt IEC 60079-28:2015 "Explosive atmospheres Part 28: Protective measures for optical radiation equipment and transmission systems" "Shi":

Compared with IEC 60079-28:2015, this document has made the following structural adjustments:

---Appendix B corresponds to Appendix D of IEC 60079-28:2015;

---Appendix D corresponds to Appendix B of IEC 60079-28:2015:

The technical differences between this document and IEC 60079-28:2015 and their reasons are as follows:

---The applicable and non-applicable scope of this document has been changed (see Chapter 1) to be consistent with the international standard interpretation sheet IEC 60079-28:2015/ISH1.2019 consistent;

---Added references to GB/T 2900.35 (see Chapter 3) and GB/T 14733.12 (see Chapter 3) to adapt to the specific conditions of our country Condition;

---Replaced IEC 60079-0 with normatively quoted GB/T 3836.1 (see Chapter 3, Chapter 4, 5:3:2, 6:1:1, Chapter 7), to adapt to my country's technical conditions and increase operability;

---Replaced IEC 60079-15 (see 5.3:2) with normatively quoted GB/T 3836.3 to adapt to my country's technical conditions and increase Operability;

---Replaced IEC 60079-11 (see 5.3:2) with normatively quoted GB/T 3836.4 to adapt to my country's technical conditions and increase Operability:

The following editorial changes have been made to this document:

---In order to be consistent with the existing standard series, the document name is changed to "Explosive Atmospheres Part 22: Optical Radiation Equipment and Transmission Systems protective measures";

---Added information about ISO and IEC terminology database addresses in terms and definitions;

---Replaced the unreferenced IEC 60050 (all parts) with GB/T 2900 (all parts) and moved it from Chapter 2 to Reference literature;

---3.12 Notes on typical optical cable structures have been added to the terms and definitions of "optical cable";

---Replaced the informatively cited international documents with Chinese documents, and revised the references:

Please note that some content in this document may be subject to patents: The publisher of this document assumes no responsibility for identifying patents:

Introduction

GB (/T) 3836 "Explosive Environment" aims to establish the basic technical requirements for equipment and applications related to explosive environments, covering it covers all aspects of the design, manufacturing, inspection, selection, installation, inspection, maintenance, repair and site classification of equipment for explosive environments, using divisional Sub-standard form, including but not limited to the following parts:

---Part 1: General requirements for equipment;

---Part 2: Equipment protected by flameproof enclosure "d";

---Part 3: Equipment protected by increased safety type "e";

---Part 4: Equipment protected by intrinsically safe "i";

---Part 5: Equipment protected by positive pressure enclosure "p";

---Part 6: Equipment protected by liquid immersion type "o";

---Part 7: Equipment protected by sand-filled mold "q";

---Part 8: Equipment protected by type "n";

---Part 9: Equipment protected by casting type "m";

---Part 11: Test methods and data for classification of gas and vapor material properties;

---Part 12: Test methods for characteristics of combustible dust substances;

---Part 13: Repair, overhaul, restoration and modification of equipment;

---Part 14: Classification of explosive gas environment locations;

---Part 15: Design, selection and installation of electrical devices;

---Part 16: Inspection and maintenance of electrical installations;

---Part 17: Equipment protected by positive pressure rooms "p" and artificial ventilation rooms "v";

---Part 18: Intrinsically safe electrical systems;

---Part 20: Equipment with isolated components or combined protection levels;

---Part 21: Application of production quality management system for explosion-proof products;

---Part 22: Protection measures for optical radiation equipment and transmission systems;

---Part 23: Class I EPLMa level equipment for use in gas and/or coal dust environments;

---Part 24: Equipment protected by special type "s";

---Part 25: Process sealing requirements between flammable process fluids and electrical systems;

---Part 26: Guidelines for Static Electricity Hazards;

---Part 27: Static electricity hazard test;

---Part 28: Basic methods and requirements for non-electrical equipment for explosive atmospheres;

---Part 29: Structural safety type "c" of non-electrical equipment for explosive atmospheres, controlled ignition source type "b", liquid immersion type "k";

---Part 30: Equipment and components for explosive environments in underground mines;

---Part 31: Equipment protected by dust ignition resistant enclosure "t";

---Part 32: Electronically controlled spark time limit intrinsically safe systems;

---Part 33: Equipment for severe working conditions;

---Part 34: Complete sets of equipment;

---Part 35: Classification of explosive dust environment locations;

---Part 36: Electrical safety devices to control potential ignition sources of explosion-proof equipment:

Optical radiation may ignite the surrounding explosive atmosphere (see ignition mechanism below): Therefore, use equipment that emits optical radiation or Equipment located outside the explosive environment but where optical radiation enters the explosive environment requires special protection against ignition: In this technology standard in terms of standardization, my country adopted IEC 60079-28:2006 to formulate GB/T 3836.22-2017 in:2017, and its technical requirements and tests Methods, etc: are specified: Since the release and implementation of the:2017 version of the standard, the protection technology for optical radiation equipment and transmission systems used in explosive environments has Certain new developments have also been made in terms of test methods: In terms of international standards, the current version of the corresponding standard is IEC 60079-28:

2015, its main technical content is applicable to our country's situation: In order to adapt to the development of explosion-proof technology and industry, and to be consistent with the development of international standards, it is necessary to GB/T 3836.22-2017 needs to be revised:

This revision adopts IEC 60079-28:2015 "Explosive atmospheres Part 28: Protective measures for optical radiation equipment and transmission systems":

On the basis of the main technical content of "Implementation", appropriate modifications have been made to adapt to the specific conditions of our country: This document serves as a special explosion-proof type department it is a supplement and modification to the general requirements of GB/T 3836.1:

When using this document, you should understand the following conditions:

Light in the form of luminaires, lasers, light-emitting diodes (LEDs), fiber optics, etc: are increasingly used in communications, exploration, sensing and measurement activities:

learning equipment: In the process of material processing, light radiation with high irradiance is often used: When such equipment is installed in an explosive atmosphere or in the vicinity of the person, radiation may pass through the explosive environment: Due to the characteristics of radiation itself, it may ignite the surrounding explosive environment: In addition, whether the presence of absorbers, such as particles, can also significantly affect ignition:

There are four possible ignition mechanisms:

a) After the surface or particles absorb optical radiation, the temperature increases, and in some cases reaches a temperature that ignites the surrounding explosive environment:

b) When the wavelength of light matches the absorption band of gas or vapor, a certain amount of flammable gas will undergo thermal ignition:

c) Radiation in the ultraviolet wavelength range causes photolysis of oxygen molecules, forming photochemical ignition:

d) The laser at the focus of the strong beam directly causes the decomposition of gas or vapor, generating plasma and shock waves, both of which eventually become ignition sources: catch Solid materials near the decomposition point exacerbate this process:

In practice, with radiant power of minimum ignition capability, the most likely cause of ignition is a): For some pulse radiation, d) will also cause points Burn: This document covers both situations: Although one should be aware of the above ignition mechanisms b) and c), due to UV radiation and most gases the absorptive properties of PTFE lead to extremely special ignition situations (see Appendix A), and this document does not cover these two situations:

This document describes the precautions and requirements to be taken when using optical radiation transmission equipment in explosive gas or explosive dust environments:

beg: This document also outlines a test method that can be used if optical limit values cannot be ensured by evaluation or beam intensity measurement:

It is used to verify that the beam has no ignition ability under selected test conditions under special circumstances:

Some equipment is outside the scope of this document because the optical radiation associated with these equipment will not be considered igniting for the following reasons Danger:

---Due to low radiant power or divergent light; and

---Hot surfaces formed due to the small distance from the radiation source to the absorber: The general requirements for lighting equipment have taken this into account:

a little:

In most cases, optical equipment is associated with electrical equipment: If the electrical equipment is located in a hazardous location, other parts of GB/T 3836 points also apply: This document provides guidance on:

a) Ignition hazards associated with optical systems in explosive environments as defined in GB 3836.14 and GB/T 3836.35; and

b) Control of ignition hazards of optical radiation equipment in explosive environments:

This document details a comprehensive system for controlling ignition hazards from optical radiation equipment in explosive environments:

Explosive atmospheres Part 22:

Protection measures for optical radiation equipment and transmission systems

1 Scope

This document specifies the requirements, testing and marking of equipment emitting optical radiation for use in explosive atmospheres, including those located outside the explosive atmosphere or Equipment protected by the explosion-proof types listed in GB/T 3836.1, but the light radiation generated will enter the explosive environment: This document includes I Class, II and III as well as EPLGa, Gb, Gc, Da, Db, Dc, Ma and Mb:

This document applies to optical radiation with a wavelength range of 380nm~10µm: Including the following ignition mechanism:

---After the surface or particles absorb light radiation, the temperature increases: Under certain conditions, it will reach a temperature that ignites the surrounding explosive environment:

---In rare special circumstances, the laser directly penetrates the gas at the focus of the strong beam, generating plasma and shock waves, which eventually become a point source of ignition: Solid materials close to the breakdown point exacerbate this process:

Note 1: See the introduction to items a) and d) of the introduction:

This document does not cover ignition of ultraviolet radiation and ignition caused by the absorption of radiation by the explosive mixture itself, nor does it include explosive absorption Ignition caused by substances or absorbents containing oxidants themselves and catalytic absorbers:

This document specifies requirements for optical radiation equipment applicable to atmospheric conditions:

This document is a supplement and modification to the general requirements of GB/T 3836.1: When the requirements of this document conflict with the requirements of GB/T 3836.1 in the event of a conflict, the requirements of this document will take precedence:

This document applies to:

a) Laser equipment;

b) Optical fiber equipment;

c) Any other concentrated light source or beam in which the light is focused on a point within the hazardous location:

Note 2: Optical components such as lenses and reflectors can convert divergent light into a convergent beam:

This document does not apply to optical radiation equipment and transmission systems with the following conditions:

---Laser equipment for ELMb, Gb or Gc and Db or Dc applications that comply with the Class 1 limits of GB 7247.1:

Note 3: The reference Class 1 limit refers to the emission limit less than 15mW measured at a certain distance from the optical radiation source in accordance with GB 7247.1: The measurement distance Reflected in explosion-proof applications:

--- A divergent light source or beam whose light is not focused in a hazardous location:

---Single or multiple optical cables that are not part of the optical fiber equipment and meet the following conditions:

- Comply with relevant industry standards and have additional protection measures, such as sturdy cables, conduits or trunking (for EPLGb, Db, Mb, Gc or Dc);

- Comply with relevant industry standards (for EPLGc or Dc):

---The optical radiation source defined in a)~c) above, the optical radiation is completely contained in an enclosure that conforms to the following explosion-proof type suitable for EPL in, or in an enclosure with the specified minimum IP rating:

- Flameproof enclosure "d" (GB/T 3836.2);

Note 4: Flameproof type "d" enclosures are suitable because ignition within the enclosure caused by a combination of optical radiation and absorbers within the enclosure is controlled:

- Positive pressure shell "p" (GB/T 3836.5);

Note 5: Positive pressure enclosure "p" is suitable because there are measures to prevent the entry of explosive gas environments:

- Respiratory restricted enclosure "nR" (GB/T 3836.8);

Note 6: Respiratory-restricted "nR" enclosures are suitable because there are measures to prevent the entry of explosive gas atmospheres: