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GB 3836.14-2014
Electrical apparatus for explosive gas atmospheres.Part 14. Classification of hazardous areas
ICS 29.260.20
K35
National Standards of People's Republic of China
Replacing GB 3836.14-2000
Explosive atmospheres - Part 14. Classification of
Explosive atmosphere
(IEC 60079-10-1.2008, IDT)
Issued on. 2014-12-05
2015-10-16 implementation
Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China
Standardization Administration of China released
Table of Contents
Introduction Ⅲ
Introduction Ⅳ
1 Scope 1
2 Normative references 1
3 Terms and definitions 2
4 General 4
4.1 Safety Principles 4
Objective 4.2 Location Category 5
5 Location Category 5 program
5.1 General 5
5.2 source of release 6
5.3 Area Type 6
5.4 6 regional
6 Ventilation 9
6.1 General 9
The main types of ventilation 6.2 9
6.3 Ventilation Level 9
6.4 ventilation effectiveness 9
7 file 9
7.1 General 9
7.2 drawings, records and data tables Table 10
Examples Appendix A (informative) source of release 11
Annex B (informative) Ventilation 16
Annex C (informative) Examples hazardous area classification 29
Annex D (informative) flammable mist 44
Figure C.1 hazardous location area is preferably 29 symbols
Figure C.2 Classification of hazardous areas schematic 43
Table A.1 influence through holes for different release levels of 12
Table B.1 independent influence of ventilation on type of zone 22
Table B.2 in V0 of multiple release summation program 22
Table B.3 1 release multiple-level summation procedure 23
Table C.1 hazardous area classification data sheet - Part 1. Details and characteristics of the flammable substance 42
Table C.2 hazardous area classification data sheet - Part 2. Released sources list 42
Foreword
All technical content in this section is mandatory.
GB 3836 "explosive atmosphere" is divided into the following sections.
Part --- 1. Equipment General requirements;
Part --- 2. the flameproof enclosure "d" protection equipment;
--- Part 3. by the increased safety "e" protection equipment;
--- Part 4. Equipment protection by intrinsic safety "i";
--- Part 5. The type pressurized enclosure "p" protection equipment;
--- Part 6. from oil immersed "o" equipment protection;
--- Part 7. from Powder filling "q" equipment protection;
--- Part 8. the "n" type protective equipment;
--- Part 9. the Encapsulation "m" protection equipment;
--- Part 11. Determination of the maximum experimental safe gap;
--- Part 12. a mixture of gases or vapors according to their maximum experimental safe gaps and minimum igniting currents;
--- Part 13. Equipment repair, overhaul, repair and modification;
Part --- 14. Classification of explosive gas environment;
--- Part 15. Electrical installations design, selection and installation;
Part --- 16. Inspection and maintenance of electrical installations;
--- Part 17. Construction and use of rooms or buildings of positive pressure;
--- Part 18. Intrinsic safety systems;
--- Part 19. Fieldbus intrinsically safe concept (FISCO);
--- Part 20. Equipment protection level (EPL) for the Ga-class equipment.
This section drafted in accordance with GB/T 1.1-2009 given rules.
This is Part 14 GB 3836's.
This Part replaces GB 3836.14-2000 "Electrical apparatus for explosive gas atmospheres - Part 14. Classification of hazardous areas", and
GB 3836.14-2000 compared to major technical changes are as follows.
--- Increased flammability mist explosion hazard high flash point liquid under pressure release (see Appendix D);
--- Thermodynamics formulas given many liquids and gases release rate estimated at the rate of release (see A.3).
This section uses the translation method is equivalent to using IEC 60079-10-1.2008 "Explosive atmospheres - Part 10-1. Classification of explosive
Atmosphere "(in English).
This part is proposed by the China Electrical Equipment Industrial Association.
This part of the National explosion-proof electrical equipment Standardization Technical Committee (SAC/TC9) centralized.
This part mainly drafted by. Nanyang Explosion Electric Institute, the national explosion-proof electrical products for Quality Supervision and Inspection Center, Long a proof electrical
Ltd., Shenzhen City Jin-Ming Technology Co., Ltd., a new dawn Technology Co., Ltd., electro explosion-proof electrical Co., Sinopec Qingdao
Full Engineering Research Institute.
The main drafters of this section. Wang Jun, Xie Shao Jian, Wu Xudong, Zhengzhen Xiao, Dan Xiaoxian, Li Xiaoning, Zhang Weihua, Zhao Hongyu.
This part of the standard replaces the previous editions are.
--- GB 3836.14-2000.
introduction
May occur in flammable gas or vapor concentration reaches a dangerous level and the number of places, explosion-proof measures should be taken to avoid the risk of explosion
risk. GB 3836 presented in this section can prevent ignition hazard assessment of the basic principles, and given that can be used to reduce such hazards
Design and control parameters guide.
Explosive atmospheres - Part 14. Classification of
Explosive atmosphere
1 Scope
GB This section 3836 specifies the possible flammable gas, vapor or mist Classification of hazardous areas (see Note 1, Notes 2 and 3),
As support proper selection and installation of electrical equipment in hazardous locations such foundation.
This section applies under standard atmospheric conditions (see Note 4), due to flammable gases or vapors mixed with air could ignite
Dangerous place, but does not apply to the following locations.
a) coal mine gas;
b) Explosives processing and manufacturing;
c) a dangerous place combustible dust or fibers that may arise (see GB 12476.3);
d) beyond the section relates to exceptions catastrophic failure (see Note 5);
e) Medical Interior;
f) residential.
This section does not consider the impact of indirect damage caused.
Together with definitions and explanations put forward based on the main principles and procedures of hazardous area classification terminology.
For detailed requirements Hazardous Locations range of industry-specific or application-specific advice can refer to the relevant industry design specifications.
Note 1. flammable mist can be formed simultaneously with the flammable vapors or appear. Despite the release of the liquid under pressure may also have flammable mist, but this section does not test
Zoning considered dangerous liquids (due to the flash point), in these cases, the strict use of gases and vapors may not be suitable as a basis for device selection.
Flammable mist information in Appendix D.
Note 2. GB 3836.15 selection and installation of equipment based on the risk of mist is not required.
Note 3. For this part, the dangerous places refers to the three-dimensional region or space.
Note 4. If the changes affect the flammable substance explosion characteristics can be negligible, then the reference atmospheric conditions including temperature and atmospheric pressure 101.3kPa
Fluctuating change 20 ℃.
Note 5. The concept of catastrophic accidents in this section is among those unexpected accidents, such as pressure vessels burst or pipe rupture.
Note 6. In any processing device, regardless of its size, in addition to electrical equipment associated with an ignition source, but also there are many possible sources of ignition. in this sense,
To ensure security, the need to take appropriate precautions in this section may be used to judge other ignition source.
2 Normative references
The following documents for the application of this document is essential. For dated references, only the dated version suitable for use herein
Member. For undated references, the latest edition (including any amendments) applies to this document.
GB/T 2900.35-2008 Electrotechnical terminology explosive atmospheres equipment [IEC 60050 (426).2008, IDT]
GB 3836.1-2010 Explosive atmospheres - Part 1. General requirements for equipment (IEC 60079-0.2007, MOD)
Temperature test method GB/T 5332-2007 flammable liquids and gases ignited (IEC 60079-4. 1975, IDT)
IEC 60079-4A to IEC 60079-4. 1966 the 1st supplementary electrical equipment for explosive gas atmospheres - Part 4. ignition
Temperature Test Method [FirstsupplementtoIEC 60079-4 (1966), Electricalapparatusforexplosivegasatmos-
pheres-Part 4. Methodoftestforignitiontemperature]
IEC 60079-20 Electrical apparatus for explosive gas atmospheres - Part 20. combustible gas and steam and electrical equipment related to the use
Gas data (Electricalapparatusforexplosivegasatmospheres-Part 20. Dataforflammablegasesand
vapours, relatingtotheuseofelectricalapparatus)
3 Terms and Definitions
GB 3836.1-2010 defined in the following terms and definitions apply to this document.
Note. Other terms and explosive atmospheres as defined in GB/T 2900.35-2008.
3.1
Explosive atmosphere explosiveatmosphere
Under atmospheric conditions, of flammable material in the form of gas, vapor, dust, fibers, or catkins with air to form a mixture, after being lit,
Able to maintain self-propagating combustion environment.
[GB 3836.1-2010, the definition 3.22]
3.2
Explosive gas atmospheres explosivegasatmosphere
Under atmospheric conditions, a mixture of flammable substances in the form of gas or vapor and air to form, after being lit, to keep from burning
Line propagation environment.
[GB 3836.1-2010, the definition 3.24]
Note 1. Although the mixture concentrations exceeding the upper explosive limit (UEL) is not an explosive atmosphere, but in some cases, the place is classified it as an explosion
Gas environmental considerations are considered reasonable.
NOTE 2. Some explosive gas concentration of 100%.
3.3
(Explosive gas atmospheres) hazardous locations hazardousarea (onaccountofexplosivegasatmospheres)
Explosive atmosphere present or expected number may appear sufficient to require construction of electrical equipment, installation and use of special
Door area measures.
3.4
(Explosive gas atmospheres) non-hazardous places non-hazardousarea (onaccountofexplosivegasatmospheres)
Explosive atmosphere is not expected to occur that do not require a lot of electrical equipment for construction, installation and use to take special precautions
Area.
3.5
Regional zones
According to the frequency and duration of an explosive gas atmospheres dangerous places into the emerging area of 3.6 to 3.8.
3.6
Zone 0 zone0
Explosive atmosphere continuously or frequently or for long periods of place.
3.7
Zone 1 zone1
In normal operation, place an explosive gas atmosphere may occasionally occur.
3.8
Zone 2 zone2
In normal operation, an explosive gas atmosphere impossible, if only for a short time existing sites.
[IEV426-03-05]
Note. Indicators Frequency and duration occurring above can be obtained from the relevant norms in a particular industry or application.
3.9
Release source sourceofrelease
Flammable gas, vapor, mist or liquid may be released can form an explosive atmosphere of the site or location.
[IEV426-03-06, modify]
3.10
Release level gradesofrelease
To minimize the frequency and the possibility of generating explosive gas atmosphere appears, will release the source is divided into three basic levels.
a) successive stages;
b) Level 1;
c) Level 2.
Sources said the release could lead to the release of the source level in any one source of release, or a combination of more than one source of release.
3.11
Continuous order release continuousgradeofrelease
Continuous release or release is expected to release frequent or long-term release.
3.12
Level 1 release primarygradeofrelease
In normal operation, expected to be released periodically or occasionally released.
3.13
Level 2 release secondarygradeofrelease
In normal operation, the release can not be expected, if the release is only occasional and short-term release is released.
3.14
The release rate releaserate
Unit time emit flammable gases, vapors or mist from the amount of released source.
3.15
Running normaloperation
It refers to equipment operating conditions within its design parameters range.
Note 1. the release of a small amount of flammable material can be considered normal operation. For example. When the transmission fluid by the pump can be seen from the release of a small amount of sealing port release.
Note 2. Fault (for example. pump seals, flange gasket damage or leakage by accident, etc.), including emergency repairs or emergency shutdown can not be regarded as normal
Run, nor can it be regarded as a catastrophic accident.
Note 3. The normal operation including start and stop the situation.
3.16
Ventilation ventilation
Because of the wind, temperature gradients, or artificial ventilation (such as a blower or fan) effect can cause air circulation and fresh air with the original set air
Change phenomenon.
3.17
Lower Explosive Limit lowerexplosivelimit; LEL
Air flammable gas, vapor or mist concentrations below the concentration of explosive atmosphere can not be formed.
Air, can not form a flammable gas environment of explosive gas, vapor or mist concentration minimum value.
[IEV426-02-09]
3.18
Upper explosive limit upperexplosivelimit; UEL
Air flammable gas, vapor or mist concentrations higher than the concentration of explosive atmosphere can not be formed.
Air, can not form a flammable gas environment of explosive gas, vapor or mist concentrations of the highest value.
[IEV426-02-10]
3.19
The relative density of gas or vapor relativedensityofagasorvapour
At the same pressure and temperature of gas or vapor density relative to the density of the air (air density of 1.0).
3.20
Flammable substance flammablematerial (flammablesubstance)
Flammable itself, or it can produce flammable gas, vapor or mist substances.
3.21
Flammable liquid flammableliquid
Under any foreseeable operating conditions, can produce flammable vapors or mist of liquid.
NOTE. Handling flammable liquid at a temperature near or above its flash point temperature is foreseeable operating conditions instance.
3.22
Flammable gas or vapor flammablegasorvapour
In a certain proportion mixed with air will form explosive gas atmosphere gases or vapors.
3.23
Flammable mist flammablemist
Volatile in the air to form an explosive atmosphere of flammable liquid droplets.
3.24
Flashpoint flashpoint
Under standard conditions, so that the liquid can be formed into a minimum amount of the liquid vapor temperature of the combustible gas/air mixture.
3.25
Boiling point boilingpoint
Atmospheric pressure conditions 101.3kPa liquid boiling temperature.
NOTE. For the initial boiling point of the liquid mixture should be used, using an initial boiling point of the liquid used to represent a range of values of the lowest boiling point, at standard test chamber was distilled
The measured value without boiling point when decomposition.
3.26
Vapor pressure vapourpressure
Pressure when the solid or liquid in equilibrium with its own vapor applied, it is the role of the material and temperature.
3.27
Ignite an explosive gas atmosphere temperature ignitiontemperatureofanexplosivegasatmosphere
Mixture under conditions GB/T 5332-2007 the provisions of flammable substances in the form of gas or vapor and air are hot list
Surface minimum temperature of ignition.
[GB 3836.1-2010, the definition 3.26]
3.28
Regional extentofzone
Was diluted from the source of release to the gas/air mixture into the air below the lower explosive limit the spatial extent (in any direction).
3.29
Liquefied flammable gas liquefiedflammablegas
In the liquid state, storage or disposal, at ambient temperature and atmospheric pressure for the combustible gas combustible matter.
4 General
4.1 Security Principles
Design, operation and maintenance of processing or storage of combustible materials complete sets of equipment should be such that the release of any flammable substance and the formation of dangerous
Range of places, either in normal operation or under other conditions are kept to a minimum, taking into account the frequency, duration and quantity released.
Check processing equipment and systems possible release of flammable material part is very important, and will consider to modify the design of such release
The possibility of release rate and frequency, and materials and minimize emissions.
These basic issues early in the process should be designed and developed the device to be checked and should be taken seriously enough research sites in classification.
In addition to the normal operating activities, such as commissioning or maintenance, site classification may be invalid, in which case you can use safe work
For the system to handle.
Where possible presence of an explosive gas atmosphere, the following measures should be taken.
a) eliminate ignition sources around explosive gas atmospheres may occur, or
b) eliminate ignition sources.
If possible, you should select and prepare some preventive measures, namely process equipment, systems and procedures, a) and b) reduce the possibility of co-existence
Small to the extent allowed. If certain measures of high reliability, or taken together to achieve the required level of safety, these measures may be used alone
use.
Objective 4.2 classification places
Classification of a method of analysis and classification of the place may be explosive gas environment for proper selection and installation
Electrical equipment in hazardous areas, to achieve the purpose of safe use. Classification is also the gas or vapor ignition characteristics such as ignition energy (gas
Category) and ignition temperature (temperature class) into account.
Use flammable substances in many physical locations, it is difficult to ensure that an explosive gas atmosphere will never occur, and ensure that the equipment never become a point
Ignition source is impossible. Thus, in a high likelihood of an explosive gas atmosphere location, using the possibility of generating a small ignition source is provided
Preparation is reliable. Conversely, if the possibility of an explosive gas atmosphere appears to reduce, you can use the structure with less stringent requirements
equipment.
After the completion of classification places, the risk assessment can be used to assess the consequences of ignition occurs in this explosive environment, in order to determine the need for mining
With a higher equipment protection level (EPL) device, or to prove lower than the normal level of protection of the device can be used. Where applicable, EPL
Requirements may be recorded in places classified documents and drawings, to allow selection of the appropriate electrical equipment.
Almost impossible by means or device is arranged around a simple check to determine which parts of the device can be divided into three regions in line with
(Zone 0, Zone 1 or Zone 2). In this regard, the need for more sophisticated methods, including basic analysis of the likelihood of an explosive gas atmosphere.
The first step is to press 0, Zone 1 and Zone definitions 2 to determine the cause of the possibility of an explosive gas atmosphere. Once the possible release
Frequency and duration (grade of release), the release rate, concentration, speed, type of ventilation and other affected regions and/or range of factors, indeed
Set around the place there may be an explosive gas atmosphere will have a reliable basis.
Therefore, this method requires more detailed consideration containing flammable material, and may be the case for each processing device to release the source.
In particular, should by design or suitable operating method, Zone 1 or Zone 0 place in or on the number range to minimize, in other words,
Plant and its equipment installation sites most appropriate for the Zone 2 or non-hazardous. There are places for the inevitable release of flammable substances, should
The processing equipment for the limit level 2 is released, if I can not (ie, level 1, or continuous release order release unavoidable place), you should try to limit the release
Volume and rate of release. When performing venues classification, these principles should be given priority consideration. If necessary, the design and processing equipment, operation and provided
It should be set to ensure that even under abnormal operating conditions released into the atmosphere of flammable substances in minimized so as to minimize the risk of workplace
range.
Once the plant were classified, and made the necessary records, it is important not in consultation with the personnel in charge of classification places when not
Allow to modify equipment or operating procedures. Unauthorized conduct Location Category invalid. All processing should ensure that the impact of classification places
Equipment maintenance and re-assembled are carefully checked before running again, to ensure the integrity of safety-related original design.
5 Classification of program
5.1 General
Classification places should understand the relevance and importance of the flammability of materials performance, familiar with the equipment and process performance professionals, but also
And understand safety, electrical, mechanical and other engineering and technical personnel qualified to negotiate.
The following terms of the possible presence of an explosive gas atmospheres hazardous location classification procedure given guidelines. Given the dangerous field in Figure C.2
Illustrates an example of the classification.
Classification places should be in the initial process, instrumentation wiring diagram and layout plan effectively, and to determine before the unit is put into operation. In the whole device
During the existence of a review should be conducted.
5.2 source of release
Fundamental factors determining the type of hazardous area is to identify the source of release and determine the grade of release.
Only flammable gas, vapor or mist with the presence of air at the same time, to the presence of an explosive atmosphere, it should determine the premises
In the presence or absence of flammable substances. In general, these flammable gases or vapors (and flammable liquids and solids may produce flammable
Gas or vapor) may be installed in a completely closed or completely closed processing equipment. To this end, the process should determine whether there is an internal device
It is flammable environment, or the release of flammable substances can produce flammable atmosphere in a process outside of the device.
Each process unit (such as tanks, pumps, pipes, containers, etc.) should be considered a potential source of release of flammable substances. If such equipment is not available
Can contain combustible materials predictable, then obviously it will not form around dangerous places. If such equipment may contain flammable
Substances, but is not released into the atmosphere (such as all welded pipe is not considered as sources of release) will also not form dangerous places.
If you have confirmed that the device will release flammable material into the atmosphere, it should first determine the approximate frequency and duration of the release, and then press rating
The definition identifies the release levels. Closed processing systems is generally believed to open the site (such as. replacement filter or feed) during the sub-venues
It should also serve as sources of release when the class. According to this method, various emission sources can be classified as "continuous level", "Level 1" or "Level 2" respectively.
After the release of the source level is determined, it should determine the release rate and extent of hazardous area type and other factors that may affect.
If the total amount available for the release of combustible materials "small", for example, laboratory use, when a potential hazard may exist, may
The property is not suitable for use classification procedure. In this case, you should consider certain risk exists.
Classification of burning combustible materials processing equipment within, for example, fuel heaters, furnaces, boilers, turbines, etc., should be considered
Cleaning cycle, startup and shutdown conditions.
Even if the liquid temperature is lower than the flash point, the combustible mist may be formed by the liquid leakage. Thus ensuring no mist is formed cloud
Important (see Appendix D).
Note. Although the mist was identified as a dangerous form, but this part of the criteria for assessing the use of gases and vapors do not apply to mist.
Area Type 5.3
There is a possibility of an explosive atmosphere depends on grade of release and ventilation, with regional recognition area is divided. 0, Zone 1,
Zone 2 as well as non-hazardous.
Note 1. Generally, the successive stages of the formation of release Zone 0, Zone 1 Class 1 release formation, the formation of the secondary release Zone 2 (see Appendix B).
Note 2. The area of overlap by adjacent sources of release have formed different types of regions, overlapping regions will use a higher classification criteria. Categories overlap region with
Meanwhile, the usual application of the general classification.
5.4 regional
Regional context refers to the size of the explosive substance diffusion concentration below the lower explosive limit before it formed an explosive atmosphere in the air, this
Size range based on calculated or estimated, taking into account the lower explosion limit appropriate safety factor. When assessing the dilution gas to its lower explosive limit or before
Vapor propagation area, should seek expert advice.
It should be noted. The gas is heavier than air may flow into place below the ground level (for example, a groove or trench); lighter-than-air gases may lag
Stay in the space above the ground (eg roof space).
If the release source is located outside the premises or nearby places, you can take the following appropriate measures to prevent a large amount of flammable gas or vapor intrusion
Places, such as.
a) physical barrier (material) layer;
b) maintaining a positive pressure near places dangerous place to prevent the gas from entering the danger;
c) with sufficient fresh air and clean place to ensure that the air may enter from flammable gas or vapor to escape all openings.
Regional level mainly by the following chemical and physical parameters affect the intrinsic properties of some flammable substances, other factors for the processing of special
some. For simplicity, assume the role of the following parameters to the other parameters remain unchanged as a precondition.
5.4.1 release rate of gas or vapor
Release rate, the greater the extent of the zone. The release rate depending on other parameters of the release of the source itself, namely.
a) the release of the geometry of the source;
This is the physical characteristics of the source of release, for examp......
......
Standard ID | GB 3836.14-2014 (GB3836.14-2014) | Description (Translated English) | Electrical apparatus for explosive gas atmospheres. Part 14: Classification of hazardous areas | Sector / Industry | National Standard | Classification of Chinese Standard | K35 | Classification of International Standard | 29.260.20 | Word Count Estimation | 50,534 | Date of Issue | 2014/12/5 | Date of Implementation | 2015/10/16 | Older Standard (superseded by this standard) | GB 3836.14-2000 | Quoted Standard | GB/T 2900.35-2008; GB 3836.1-2010; GB/T 5332-2007; IEC 60079-4A; IEC 60079-20 | Adopted Standard | IEC 60079-10-1-2008, IDT | Drafting Organization | Nanyang Institute of Electrical Explosion | Administrative Organization | National Standardization Technical Committee explosion-proof electrical equipment | Regulation (derived from) | Announcement of Newly Approved National Standards 2014 No. 27 | Proposing organization | China Electrical Equipment Industry Association | Issuing agency(ies) | General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China | Summary | This Standard specifies the possible flammable gas, vapor or mist Classification of hazardous areas (see Note 1, Notes 2 and 3), as supporting the proper selection and installation of electrical equipment in hazardous locations such foundation. This secti | Standard ID | GB 3836.14-2000 (GB3836.14-2000) | Description (Translated English) | Electrical apparatus for explosive gas atmospheres. Part 14: Classification of hazardous areas | Sector / Industry | National Standard | Classification of Chinese Standard | K35 | Classification of International Standard | 29.260.20 | Word Count Estimation | 43,435 | Date of Issue | 2000-10-17 | Date of Implementation | 2001-06-01 | Quoted Standard | IEC 60050 (426)-1990; IEC 60079-4-1975; IEC 60079-4A-1970 | Adopted Standard | IEC 60079-10-1995, IDT | Drafting Organization | Explosion Protection Electric Institute | Administrative Organization | Explosion-proof electrical equipment of the National Technical Committee | Proposing organization | National Machinery Industry Bureau | Issuing agency(ies) | State Quality and Technical Supervision | Summary | This Chinese standard specifies the possible flammable gases or vapors Classification of hazardous areas in order to properly choose and install these hazardous area electrical equipment. This standard applies under normal conditions as a result of flammable gas or vapor and air mixture could ignite dangerous places. |
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