Note to paragraph (g)(5)(ii)(C) of this section: The National Electrical Code, NFPA 70, contains guidelines for determining the type and design of equipment and installations that will meet this provision. Type of protection "n" is further subdivided into nA, nC, and nR. Flammable liquids with a high flash point are less hazardous than liquids [12], International Electrotechnical Commission, Occupational Safety and Health Administration, National Electrical Manufacturers Association, "Hazardous Area Classification and Control of Ignition Sources", "Hazardous (Classified) Locations NEC Articles 500 through 517", https://en.wikipedia.org/w/index.php?title=Electrical_equipment_in_hazardous_areas&oldid=1134828101, ignitable concentrations of combustible dust can exist, under normal conditions, ignitable concentrations of combustible dust are unlikely to exist normally, ignitable fibers, or materials producing combustible flyings, are handled, manufactured or used, easily ignitable fibers are stored or handled. This was accompanied by electrically-initiated explosions of flammable gas such as fire damp (methane) and suspended coal dust. 2: This classification includes, Informational Note No. Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 September 2019. The inductance of the signal bell coils, combined with breaking of contacts by exposed metal surfaces, resulted in sparks, causing an explosion. As a result, all hazardous area equipment must be designed with hazardous area zone classifications in mind, as the zone governs the level of protection and precaution required. Temporary Refuge For example the EI 15 and API 500/505 describe specific installations and several conditions for the oil and gas industry. The value is represented is volume percentage of oxygen. When working in or specifying equipment for use in hazardous environments, we see a lot of confusion in the industry regarding the different certifications and requirements. 14 4. The substance referred to by classhas a low probability of producing an explosive or ignitable mixture and is present only during abnormal conditions for a short period of time - such as a container failure or system breakdown. As mentioned, the first important step of achieving a safe work environment in relation to explosion safety is to identify and classify those areas, where a concentration of flammable gases or vapors within the flammable range can be present. The Zone system is based on Article 505/506 of the National Electrical Code (NEC) and follows the international method of area classification as developed by the International Electrotechnical Commission (IEC). The Zone Classification System is offered as an alternative to the Class and Division system. Zones also have the added benefit of including the area classification with the zone description. This is an important factor in the classification of hazardous areas. September 2020 Analysers, motors, control boxes, computers, Any arcs or sparks in this equipment has insufficient energy (heat) to ignite a vapour. NEGATIVE PRESSURE 1.1 Scope. Area Classification - Hazardous Locations are classified by the likelihood of an ignitable concentration of combustible material being present. Informational Note No. 29 CFR 1910.399 Definitions Applicable to Subpart S A Zone defines the general nature - if it is a gas or dust - and the probability of hazardous material being present in an ignitable concentration in the surrounding atmosphere. September 2019 Q: Can I use a piece of equipment approved for use in a Division 1 hazardous location in a Division 2 hazardous location? An area where combustible dusts or ignitable fibers and flyings are likely to occur under normal operating conditions. Raytec do not currently offer any lighting solutions for Zone 0. The hazardous area classification system determines required protection techniques and methods for electrical installations in the location. 5: For further information on ventilation, see NFPA 30-2018, Informational Note No. Many items of EEx rated equipment will employ more than one method of protection in different components of the apparatus. 286 natural gas explosions per year in the U.S. causing substantial damage, severe injury or loss of lives. Beside sufficient fuel, also sufficient oxygen is needed for combustion of the mixture. Areas with possible fire or explosion risks due to explosive atmospheres and/or mixtures - are called hazardous (or classified) locations or areas. (equivalent to NEC Class I, Groups A and B), (equivalent to NEC Class II, Groups F and G), Group IIC is the most severe zone system gas group. Locations are thus classified by type and risk of release of gas, vapor, or dust. Conversely if the same material is heated and handled above its flash-point, the area must be classified for proper electrical system design, as it will then form an ignitable mixture.[5]. The more hazardous the area to more safety measures have to be taken in order to prevent equipment becoming an effective source of ignition. . we will look at what defines Zone 0, Zone 1 and Zone 2 hazardous area classifications and the considerations for specifying lighting into each area. Area's are divided into zones. These areas are classified solely for the purpose of ensuring the safe and proper specification and installation of electrical/electronic equipment. The simplest is to minimize the amount of electrical equipment installed in a hazardous location, either by keeping the equipment out of the area altogether, or by making the area less hazardous (for example, by process changes, or ventilation with clean air). A differentiation is made between gas Ex zones and dust Ex zones: Gas Ex zones are 0/1/2 and dust Ex zones are 20/21/22. Informational Note No. Several protection strategies exist. Classification of Hazardous Areas 0 100 200 300 400 500 600 T1 >450C T2 >300C 450C T3 >200C 300C T4 >135C 200C . Intrinsic safety designs equipment to operate using minimal energy, insufficient to cause ignition. Dry Container September 2021 The following Equipment Groups and Categories are applicable: Equipment in this category is only intended for use in the underground areas of mines, as well as those areas of surface installations of such mines endangered by firedamp and/or combustible dusts. Industrial electrical equipment for hazardous area has to conform to appropriate parts of standard: IEC-60079 for gas hazards, and IEC-61241 for dust hazards. Various regulations use terms such as class, division, zone, and group to differentiate the various hazards. Encapsulation "m" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. Both external and internal temperatures are taken into consideration. 2: Through the exercise of ingenuity in the layout of electrical installations for hazardous (classified), Refrigerant machinery rooms that contain ammonia refrigeration systems and are equipped with adequate mechanical ventilation that operates continuously or is initiated by a detection system at a concentration not exceeding 150 ppm shall be permitted to be classified as "unclassified". February 2023 Zone 1: An area in which an explosive atmosphere is likely to occur in normal operation. December 2013, All Substances characterization Consequences . To make this even easier to understand, take a look at the diagram of a typical petrol station below where we have identified the areas that are classified as Zone 0, Zone 1 and Zone 2. Well recognized and clear IEC Standard IEC 60079-10-2:2015 Hazardous Area Classification for explosive dusts Significant influence on spending's for safety . Ex Zone. Class I hazardous locations are identified by zones as follows: * Zone 0 a location in which explosive gas atmospheres are present continuously or for long periods of time. Much early equipment having Ex s protection was designed with encapsulation and this has now been incorporated into IEC 60079-18 [Ex m]. The Hazardous Area Classification presents in this guide is based on the following items as reference: API: API RP 505 Recommended Practice for Classification of Locations for Electrical. Non-hazardous or ordinary locations. If you require more information on the different variants in the SPARTAN range, or you would like to discuss your application in more detail, you can call us on +44 (0) 1670 520055 or send an email to sales@raytecled.comwhere we will happily answer any questions you have. Horizontal. Canada has a similar system with CSA Group standard C22.1, the Canadian Electrical Code, which defines area classification and installation principles. In Northerm America, instead of the zone classification system, the Class/Division system is used. ESS Container Determining the Class, Division and Group or Zone and Group is critical to correctly applying the requirements for a given hazardous location. A high level of protection is ensured. 5mm -750C Electrical Resistivity. NEC has created an Americanized version of the IEC/CENELEC Zone system in a stand-alone article (Article 505). Area classification is not simply intended to identify hazardous areas on process plants where design has already been completed using only operational and economic factors as influence,. Equipment shall be marked in accordance with paragraph (g)(5)(ii)(A) and (g)(5)(ii)(B) of this section, except as provided in (g)(5)(ii)(C). Upon detection, appropriate action is automatically taken, such as removing power, or providing notification. . A hazardous area classification drawing (also known as an area classification drawing) outlines the classifications of areas where flammable liquids, gasses or vapors are handed, processed or stored. Note to paragraph (c)(2)(i) of this section: NFPA 70, the National Electrical Code, lists or defines hazardous gases, vapors, and dusts by "Groups" characterized by their ignitable or combustible properties. Zone 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. coal and charcoal), Group G Nonconductive dusts (eg. Beside the Lower Explosion Limit, each substance also has an Upper Explosion Limit (UEL). Outside of the United States, the IEC uses two different classifications: Gas & Vapor (Zones 0, 1, or 2) Dust (Zones 20, 21, or 22) Step 2: The next step is to determine how often the hazardous substance (s) is/are present. A more quantitative method is described in IEC 60079-10-1 but also more sophisticated numeric mathematical models can be used like Computational Fluid Dynamics. The required protection level is linked to the intended use in the zones described below: The equipment category indicates the level of protection offered by the equipment. Zone 0, 1, and 2 locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. These would be then labeled with each of the individual methods. (between 0,1 and 10% of the time). Hazardous areas are defined as: " Zones " under worldwide IEC standards (and their local versions, such as ATEX in Europe) " Divisions " under North American NEC standards. >> For Gas Vapor this would be Zone 1. Some equipment in Division 2 areas do not require a specific label, such as standard 3 phase induction motors that do not contain normally arcing components. The NEMA enclosure rating or IP code may also be indicated, but it is usually independent of the Classified Area suitability. The plan may contain the list of chemicals with their group and temperature rating. I Flammable gases or vapors may be present, 1 Ignitable concentrations of hazards exist under normal operation conditions and/or where the hazard is caused by frequent maintenance or repair work or frequent equipment failure, E Combustible metal dusts: aluminum, commercial alloys and magnesium, III Easily ignitable fibers or flyings may be present, 0 Ignitable concentrations of flammable gases or vapors which are present continuously or for long periods of time, 1 Ignitable concentrations of flammable gases or vapors which are likely to occur under normal operating conditions; may exist frequently because of repair/maintenance operations or leakage; or equipment is operated in a manner that equipment breakdown/faulty operations could result in the release of ignitable concentrations of flammable gases or vapors and failure of the equipment, 2 Ignitable concentrations of flammable gases or vapors which are not likely to occur under normal operating conditions and if they do will only persist for a short period of time; or volatile flammable liquids, gases, or vapors are confined within closed containers/systems and can escape only as a result of an accidental rupture; or volatile flammable liquids, gases, or vapors are normally prevented by positive mechanical ventilation, but may become hazardous due to system failure, 20 Combustible dusts or ignitable fibers/flyings are present continuously or for long periods of time, 21 Combustible dusts or ignitable fibers/flyings are likely to occur under normal operating conditions; or may exist frequently because of repair/maintenance operations or leakage; or equipment is operated in a manner that breakdown/faulty operations could result in the release of ignitable concentrations of combustible dust or fibers/flyings and failure of the equipment, 22 Combustible dusts or ignitable fibers/flyings are likely to occur under normal operating conditions; or may exist frequently because of repair/maintenance operations or leakage; or equipment is operated in a manner that breakdown/faulty operations could result in the release of ignitable concentrations of combustible dust or fibers/flyings and failure of the equipment, Mines susceptible to firedamp (flammable mixture of gases naturally occurring in a mine, Explosive dusts Group III equipment is subdivided into three subgroups, A Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or gases/vapors of equivalent hazard, A Atmospheres containing solid particles and fibers greater than 500 microns that could be suspended in air and settle out, B Atmospheres containing acetaldehyde, ethylene, or gases / vapors of equivalent hazard, B Atmospheres containing combustible dusts other than combustible metal dusts, C Atmospheres containing acetylene, hydrogen, or gases/vapors of equivalent hazard, C Atmospheres containing combustible metal dusts. Area which are not devided into Atex zones, are called non-hazardous area's. Definition of hazardous area zones (AS/NZS 60079.10): Zone 0 June 2019 National Electrical Code, NFPA 70, Chapter 5, Article 500, 29 CFR 1910 Subpart S, Electrical 1910.307, NFPA 497, "Classification of Gases, Vapors, and Dusts for Electrical Equipment in Hazardous Classified Locations", NFPA Handbook, "Electrical Installations in Hazardous Locations, " by P. J. Schram and M. W. Earley, NFPA 70E, Chapter 5, "Hazardous (Classified) Locations", ANSI/UL 913, "Intrinsically Safe Apparatus", NFPA 496, "Purged and Pressurized Enclosure for Electrical Equipment in Hazardous Locations. In this system, two bare wires were run along the length of a drift, and any miner desiring to signal the surface would momentarily touch the wires to each other or bridge the wires with a metal tool. Equipment approved for use in Class I hazardous locations cannot be used in Class II hazardous locations. Equipment of the nonheat-producing type, such as junction boxes, conduit, and fittings, and equipment of the heat-producing type having a maximum temperature not more than 100 C (212 F) need not have a marked operating temperature or temperature range; Electric equipment suitable for ambient temperatures exceeding 40 C (104 F) shall be marked with both the maximum ambient temperature and the operating temperature or temperature range at that ambient temperature; and. Within a working area or installation an ignition can be created by many factors. >> NEC: Class I, Division 2, Group D. | IEC: Zone 2, Group II. And safety must be guaranteed in the case of two faults occurring independently of each other. Empirical testing is done to determine parameters such as the maximum experimental safe gap (MESG), minimum igniting current (MIC) ratio, explosion pressure and time to peak pressure, spontaneous ignition temperature, and maximum rate of pressure rise. gas, vapours, mists and dusts). All equipment in Division 1 areas must have an approval label, but certain materials, such as rigid metallic conduit, does not have a specific label indicating the Cl./Div.1 suitability and their listing as approved method of installation in the NEC serves as the permission. Zone 1 - Explosive atmospheres are likely to occur. In Europe the label must show the CE mark and the code number of the certifying/notified body). When equipment must be placed in a hazardous location, it can be designed to reduce the risk of fire or explosion. . eg Production Area, area surrounding zone 0. The Zone system for classifying hazardous locations used in NFPA 70 NEC, IEC 60079, and the Canadian Electrical Code indicates the level of probability that a flammable concentration of a hazardous substance may be present. may exist under normal or abnormal conditions because of the presence of flammable gases or vapors, combustible dusts or ignitable fibers or flyings. | For Dust this would be Zone 22. For dusts: Zone 20, Zone 21 and Zone 22. Cookies are only used in the browser to improve user experience. Type of protection "n" -- This protection technique is permitted for equipment in the Class I, Zone 2 locations for which it is approved. Subscribe 6.9K views 2 years ago Oil and Gas Zone Classifications: A) Hazardous Area Classification It's cable reimagined No DVR space limits. February 2019 Group II is for explosive gases (Zone 0, 1 and 2) and Group III is for explosive dusts (Zone 20, 21 and 22). Atmosphere containing a flammable gas, a flammable liquid produced vapor, or a combustible liquid produced vapor mixed with air that may burn or explode, having either a MESG (Maximum Experimental Safe Gap)1) value less than or equal to 0.45 mm or aMIC (Minimum Igniting Current)2) ratio less than or equal to 0.40 - such as hydrogen or fuel and combustible process gases containing more than 30% hydrogen by volume - or gases of equivalent hazard such as butadiene, ethylene oxide, propylene oxide and acrolein. March 2022 In many industrial, commercial, and scientific settings, the presence of such an atmosphere is a common, or at least commonly possible, occurrence. The disadvantage of standards with example installations, is that a huge safety factor is incorporated and thus relative large hazardous area are defined. Documentation requirements likewise vary. Zone 0 - Explosive atmospheres present continuously long periods or frequently. Informational Note No. This page was last edited on 20 January 2023, at 22:32. with hazardous areas EC-Type Examination Certificate BAS 01 ATEX 7251 , for additional certificates see www.pepperl-fuchs.com Group, category, type of protection II (1) G D [EEx ia] IIB (-20 C Ta 60 C) [circuit(s) in zone 0/1/2] Output EEx ia IIB Voltage U0 25.9 V Current I0 184 mA Power P0 1.2 W Type of protection [EEx ia] In electrical and safety engineering hazardous locations HazLoc pronounced hazlk are places where fire or explosion hazards may exist. But first, we must consider what is likely to cause an explosion in the first place. Readers with specific questions should refer to the applicable standards or consult with an attorney. There are several ways of how to perform hazardous area classification, all described in several standards or codes of practise. Enclosures can be pressurized with clean air or inert gas, displacing any hazardous substance. Purged and pressurized -- This protection technique is permitted for equipment in the Class I, Zone 1 or Zone 2 locations for which it is approved. Electrical equipment installed in such locations can provide an ignition source, due to electrical arcing, or high temperatures. Zones 1 or 2. So, it is good to know that when a flammable substance concentration exceeds the LEL, it will not automatically lead to an explosion with the highest Pmax. WATER TIGHTNESS We don't save this data. 3: For further information on the classification of, Informational Note No. November 2020 Home About Us News Hazardous Environment Classifications: NEC vs IEC, Posted March 11, 2019 by springercontrols. Where there is potential for an explosive atmosphere, special precautions are needed to prevent fires and explosions. 2: This classification usually includes, (B) Special Occupancies, Zone 0, 1, and 2 Locations, Article 505 Special Occupancies, Zone 0, 1, and 2 Locations, (B) Special Occupancies, Class I, Zone 0, 1, and 2 Locations, National Electrical Code 2020 of Illinois, National Electrical Code 2017 of Illinois, Ignitible concentrations of flammable gases or vapors are present continuously, Ignitible concentrations of flammable gases or vapors are present for long periods of time, In which ignitible concentrations of flammable gases or vapors are likely to exist under normal operating conditions; or, In which ignitible concentrations of flammable gases or vapors may exist frequently because of repair or maintenance operations or because of leakage; or, In which ignitible concentrations of flammable gases or vapors are not likely to occur in normal operation and, if they do occur, will exist only for a short period; or, In which volatile flammable liquids, flammable gases, or flammable vapors are handled, processed, or used but in which the liquids, gases, or vapors normally are confined within closed containers of closed systems from which they can escape, only as a result of accidental rupture or breakdown of the containers or system, or as a result of the abnormal operation of the, In which ignitible concentrations of flammable gases or vapors normally are prevented by positive mechanical ventilation but which may become hazardous as a result of failure or abnormal operation of the ventilation. December 2021 LIFTING TEST It is obvious to use those standards within these industries. A: Yes. 1: The term "Class I" was originally included as a prefix to, Informational Note No. PROCESS OF CONTAINER In an ordinary household this is of no concern, but if a flammable atmosphere is present, the arc might start an explosion. The autoignition temperature is the lowest temperature at which the substance will ignite without an additional heat or ignition source (at atmospheric pressure). CLASSIFIED LOCATIONS: AREA CLASSIFICATION: AREA CLASSES: AREA GROUPS: LOCATION AS PER DIVISIONS: DIVISION 1 - Class I, Division 1 hazardous locations are defined (as per NEC code Article 500) as follows: DIVISION 2 - Class I Division 2 Locations are as follows: Area Classification by ZONES: DEFINITIONS: HAZARDOUS LOCATIONS: Q: Are Divisions and Zones equivalent to one another? Hazardous areas are classified into zones based on an assessment of the frequency of the occurrence and duration of an explosive gas atmosphere, as follows: Zone 0: An area in which an. Therefore, it is very important to make sure that you are using a suitable luminaire for your application by choosing your fitting based on its suitability for the Zone in which it will be located. October 2018 IECEx Karandikar Certification All emergency versions, whether Zone 1 or Zone 2 can also be easily visually identified by their red end cap, encapsulating the emergency battery back-up. Ignitable concentrations of flammable gases or vapors which are likely to occur under normal operating conditions. An oversimplification of this example is shown in Table 1. The temperature marking may not exceed the ignition temperature of the specific gas or vapor to be encountered. WELDING INSPECTION In effect it is any method which can be shown to have the required degree of safety in use. Carbon monoxide, ether, hydrogen sulfide, . The term equipment is applied both for fixed equipment and mobile equipment that are operated in such area. This temperature is used for classification for industry and technology applications.[6]. There are four zones in the IEC classification system: Zone 0: An area in which an explosive atmosphere is present continuously or for long periods. Arcing electrical equipment in unclassified . A room with a propane gas installation will typically be classified with the. Oil Immersion "o" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. Read more in our blogWhich Standards to use for Hazardous Area Classification. Not only are hazardous areas classified by Class (nature of the hazardous material,) and Division . . Zones compares to classes and divisions in the Class/Division system. Zone 2: An area in which an explosive atmosphere is not likely to occur in normal operation, but if it does . Iso Container Have a think about it next time youre filling up! This level of risk is represented by classifying the hazardous area as Zone 0, Zone 1 or Zone 2 (for gas, vapour and mist atmospheres) or Zone 21 or Zone 22 for dust atmospheres. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. Guidance on assessment of hazards is given in NFPA497 (explosive gas) and NFPA499 (dust). July 2019 The equipment group . . But every hazardous area is different and each has specific requirements depending on the nature of the atmosphere and the elements that are present. Safe for the hazardous (classified) location. You can target the Engineering ToolBox by using AdWords Managed Placements. The colour of the luminaire body indicates the level of protection. This classification method provides a description of the hazardous material that may be present, and the probability that it is present, so that the appropriate equipment may be selected, and safe installation practices followed. Zone 2 hazardous areas are typically storage areas but can also be process areas. Zone 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. Only emails and answers are saved in our archive. Zone 1 (unless separated by a fire wall)P.G.Sreejith, Kerala. Magnesium, Titanium), IIB Nonconductive dusts (eg. In general, all types of equipment installed within the hazardous area shall be . Class I, Zone 0 = Area Classification, AEx = Symbol for equipment built to American specifications, ia = Type of protection designations, IIC = Gas classification group (as required), T6 = Temperature Classification, [46 FR 4056, Jan. 16, 1981; 46 FR 40185, Aug. 7, 1981; 72 FR 7210, Feb. 14, 2007], Occupational Safety & Health Administration. Source: Rules and Regulations for the Classification of Mobile Offshore Units, Part 7, Safety Systems, Hazardous Areas and Fire, June 2013, Lloyd's Register, Global Standards. A spark or high heat must also be present. So the flammable range of a substance is the concentration of gases and vapors in air between the Lower Explosion Limit and the Upper Explosion Limit. 3: Text that is followed by a reference in brackets has been extracted from NFPA 497-2017, All other applicable rules contained in this, Where the term "Class I" is used with respect to, Informational Note: The term "Class I" was originally included as a prefix to, All areas in industrial occupancies designated as hazardous (classified). 1: As a guide to classification of Zone 22 locations, refer to ANSI/ISA 60079-10-2 (12.10.05)-2013, Explosive Atmospheres Part 10-2: Classification of areas Combustible dust atmospheres. Offshore Accommodation Module Motors, lighting, junction boxes, electronic equipment, This method, being by definition special, has no specific rules. No. Hazardous areas are classified into 3 zones based upon the frequency of the occurrence and duration of an explosive gas atmosphere, as follows: Zone 0 Area in which an explosive gas atmosphere is present continuously or for long periods or frequently. Dn 2 - a Ce d e r . This blog post will focus on the different hazardous location classifications and well follow up with another that discusses how equipment can be constructed and certified for use in these environments. Electrical equipment installation in atmosphere with flammable gases or vapors, flammable liquids, combustible dusts, ignitable fibers or flyings represents a risk for fire and explosion. Division defines the likelihood of the hazardous material being present in an explosive or ignitable concentration.Class I flammable gases and vapors are grouped into one of four groups(Groups A, B, C or D)based on their physical properties and the ease in which they can be ignited. Sources of such hazards include gases, vapors, dust, fibers, and flyings, which are combustible or flammable. [10][11] Some of these are specifically for hazardous locations: All equipment certified for use in hazardous areas must be labelled to show the type and level of protection applied.