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. This article covers the requirements for the, Informational Note No. Equipment that is listed for a Zone 1 location may be installed in a Zone 2 location of the same gas or vapor. Temporary Refuge (TR) Shelter 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. Zone 0/20: An area in which an explosive atmosphere is present continuously or for long periods or frequently. Zones. For explosion hazards caused by flammable liquids or gases, the following zones are defined: So a zone 0 is the most hazardous zone and a zone 2 is a less hazardous zone. Informational Note No. The temperature classification on the electrical equipment label will be one of the following (in degree Celsius): The above table shows that the surface temperature of a piece of electrical equipment with a temperature classification of T3 will not rise above 200C. However, the following provisions modify this marking requirement for specific equipment: Fixed lighting fixtures marked for use in Class I, Division 2 or Class II, Division 2 locations only need not be marked to indicate the group; Fixed general-purpose equipment in Class I locations, other than lighting fixtures, that is acceptable for use in Class I, Division 2 locations need not be marked with the class, group, division, or operating temperature; Fixed dust-tight equipment, other than lighting fixtures, that is acceptable for use in Class II, Division 2 and Class III locations need not be marked with the class, group, division, or operating temperature; and. Equipment that is safe for the location shall be of a type and design that the employer demonstrates will provide protection from the hazards arising from the combustibility and flammability of vapors, liquids, gases, dusts, or fibers involved. Division 2 is equivalent to Zone 2, while Division 1 is either Zone 0 or 1. 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] Equipment in this category is intended for use in areas in which explosive atmospheres caused by gases, vapours, mists or air/dust mixtures are likely to occur occasionally. This is presented by the Lower Explosion Limit (LEL) of a substance. The flash-point is the temperature at which the material will generate sufficient quantity of vapor to form an ignitable mixture.
Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 . A spark or high heat must also be present. This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. NEC 2 Divisions (Div 1 2) Division I Comprising of Area Same as Zone 0 1. Comparison of Zone 2 and Division 2 TABLE 1 - AREA CLASSIFICATIONS Division 1: Where ignitable concentrations can exist all of the time or some . An area where combustible dusts or ignitable fibers and flyings are not likely to occur under normal operating conditions and do so only for a short period of time. Offshore Accommodation Module Equipment should be tested to ensure that it does not exceed 80%[according to whom?] Category 3 equipment may only be used in zone 2 areas. Both external and internal temperatures are taken into consideration. 1.1.1 This recommended practice applies to those locations where flammable gases or vapors, flammable liquids, or combustible liquids are processed or handled; and where their release into the atmosphere could result in their ignition by electrical systems or equipment. IEC 60079-10-1 covers classification of explosive gas atmospheres, and IEC 60079-10-2 explosive dust. Have a think about it next time youre filling up! .
Hazardous Area Classification - What You Must Know About Note to paragraph (c)(3) 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 requirement. All threaded conduit shall be threaded with an NPT (National (American) Standard Pipe Taper) standard conduit cutting die that provides -in. Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse! Category 1 equipment may be used in zone 0, zone 1 or zone 2 areas. | For Dust this would be Zone 21. All rights reserved. Class I, Zone 0 or Zone 1 locations may not abut Class I, Division 1 or Division 2 locations. A Zone 0 location is a location in which one of the following . . This value of this LOC differs per substance and depends also on the inert gas for achieving a low oxygen concentration. Zones 0, 1 and 2: Atmospheres with explosive gases and vapours (AS2380; AS/NZS/IEC 60079) Zone 0 Area The definition according to IEC60079-10-1 is "an area in which an explosive gas atmosphere is present continuously or for long periods or frequently". October 2018 4: For further information on protection against static electricity and lightning hazards in hazardous (classified). Every substance has a differing combination of properties but it is found that they can be ranked into similar ranges, simplifying the selection of equipment for hazardous areas. 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. There are three necessary components for an explosion to occur; This needs to be present in a relatively high quantity to produce an explosive mixture (e.g. The key difference between Divisions and Zones relate to terminations. This is an important factor in the classification of hazardous areas. Fundamentally, for an explosion to take place, flammable or explosive gases, vapours, mists or dusts will be present. For more detailed assessments or for situations where no specific industry standards are available , like the chemical or pharmaceutical sector and also specific installation for oil and gas industries, a more quantitative approach can be used. Hazardous locations can also be described as those locations where electrical equipment
of the autoignition temperature of the hazardous atmosphere. Classification of Hazardous Areas 0 100 200 300 400 500 600 T1 >450C T2 >300C 450C T3 >200C 300C T4 >135C 200C . 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.
PDF Hazardous locations - CEC classifications To minimize the risk of these fires or explosions, electrical/electronic equipment must be designed, tested and labeled as being acceptable for use in the areas in which it is installed. It uses the familiar Class/Division system and adapts the IEC/CENELEC Zones into it while maintaining NEC wiring methods and . When comparing Divisions and Zones, Division 2 is equivalent to Zone 2, but Division 1 is equivalent to either Zone 0 or 1. Area Classification - Hazardous Locations are classified by the likelihood of an ignitable concentration of combustible material being present. Table 1. Within a working area or installation an ignition can be created by many factors. ethanol, methane or hydrogen. In Northerm America, instead of the zone classification system, the Class/Division system is used. 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 Raytec SPARTAN range includes dedicated luminaires for both Zone 1 and Zone 2 areas as well as industrial applications. NFPA 70, the National Electrical Code (NEC), defines area classification and installation principles. What Are All Those Gadgets On A Multitool? MCC Shelter The types of protection are subdivided into several sub classes, linked to EPL: ma and mb, px, py and pz, ia, ib and ic. The lower explosion limit of a substance is the lowest concentration (in volume percentages for gases and liquids) of a gas or a vapor in air of producing a flash of fire in the presence of an ignition source. This leads to a lot of the confusion in the global marketplace because certifying equipment to these different systems can be time consuming and expensive, so many companies may only certify to one or the other. Since the changes to the code, hazardous locations with gases or vapors (Class I) present can be reclassified as Zone 0, 1 or 2. 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. Controls can be fitted to detect dangerous concentrations of hazardous gas, or failure of countermeasures. The substance referred to by classhas a high probability of producing an explosive or ignitable mixture due to it being present continuously, intermittently, or periodically or fromthe equipment itself under normal operating conditions. 2: Where gas detection, Informational Note No. 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. 2: For the requirements for electrical and electronic. Encapsulation "m" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. Class I Zone 2 Hazardous Areas. That flammable gas or vapor . Unlike ATEX which uses numbers to define the safety "Category" of equipment, namely (1,2 3), the IEC continued to utilise the method used for defining the safe levels of intrinsic safety namely "a" for zone 0, "b" for zone 1 and "c" for zone 2 and apply this Equipment Level of Protection to all equipment for use in hazardous areas since 2009. 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. The classification process requires the participation of operations, maintenance, safety, electrical and instrumentation professionals; and the use of process diagrams, material flows, safety data sheets, and other pertinent documents. FEA Group II is for explosive gases (Zone 0, 1 and 2) and Group III is for explosive dusts (Zone 20, 21 and 22). Increased safety "e" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. For Zone 1 applications, Pyroban uses . [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. In the IEC standards hazardous areas are classified into zones based upon the frequency and duration of an explosive atmosphere. Refrigerated Container 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. | For Dust this would be Zone 22. IEC 60079-10.1 Classification of areas - Explosive gas atmospheres. With the advent of electric power, electricity was introduced into coal mines for signaling, illumination, and motors. Dry Container The IEC 60079 standard set has been adapted for use in Australia and New Zealand and is published as the AS/NZS 60079 standard set. Determining the Class, Division and Group or Zone and Group is critical to correctly applying the requirements for a given hazardous location. A Class I, Division 1 or Division 2 location may be reclassified as a Class I, Zone 0, Zone 1, or Zone 2 location only if all of the space that is classified because of a single flammable gas or vapor source is reclassified. Class I: hazardous because flammable gases or vapors are present in the air in quantities sufficient to produce explosive or ignitable mixtures: . Such areas include a residence or office where the only risk of a release of explosive or flammable gas would be such things as the propellant in an aerosol spray. The above groups are formed in order of how explosive the material would be if it was ignited, with IIC being the most explosive zone system gas group and IIA being the least. Horizontal. PROCESS OF CONTAINER December 2013, All to EN 1127-1): After the hazard area classification is completed, then the ignition assessment starts. Container Accessories Gas a.
PDF HazLoc Hand Chart That is why the use of mobile phones on petrol forecourts are banned. A: No. The escaping (hot) gases must sufficiently cool down along the escape path that by the time they reach the outside of the enclosure not to be a source of ignition of the outside, potentially ignitable surroundings. >> NEC: Class II, Division 1, Group F. | IEC: Zone 20, Group IIC. The American Petroleum Institute publishes analogous standards in RP500 andRP505. Areas with possible fire or explosion risks due to explosive atmospheres and/or mixtures - are called hazardous (or classified) locations or areas. So the following conditions must be met for an explosion to occur: Represented by the following explosion triangle. >> NEC: Class I, Division 2, Group D. | IEC: Zone 2, Group II. Area ClassificationThe max surface temp. 286 natural gas explosions per year in the U.S. causing substantial damage, severe injury or loss of lives. Zone 1 (unless separated by a fire wall)P.G.Sreejith, Kerala. The two general approaches are: Several techniques of flame-proofing exist, and they are often used in combination: Equipment has flameproof gaps (max 0.006" (150m) propane/ethylene, 0.004" (100m) acetylene/hydrogen), Equipment can be installed in ANY housing provided to IP54.A 'Zener Barrier', opto-isolator or galvanic unit may be used to assist with certification. Typical gas hazards are from hydrocarbon compounds, but hydrogen and ammonia are also common industrial gases that are flammable. Readers with specific questions should refer to the applicable standards or consult with an attorney. See below for further details: Division system sample marking Zone 1 2. These areas are in North America (United States and Canada) historically classified with the Class/Division system.
ATEX Zones - Hazardous Area Classification - HET Filter In Europe the label must show the CE mark and the code number of the certifying/notified body). Atmospheres containing ethylene, propylene oxide, ethylene oxide, butadiene, cyclopropane, ethyl ether, or gases and vapors of equivalent hazard. Informational Note No.
Hazardous Area Classification - [PDF Document] NEC has created an Americanized version of the IEC/CENELEC Zone system in a stand-alone article (Article 505). The design of the equipment must ensure protection, even in the event of rare incidents relating to the equipment. Type of protection "n" is further subdivided into nA, nC, and nR. Magnesium, Aluminum, Titanium etc. 1) MESG (Maximum Experimental Safe Gap) - The maximum clearance between two parallel metal surfaces that has been found under specified test conditions to prevent an explosion in a test chamber from being propagated to a secondary chamber containing the same gas or vapor at the same concentration. Equipment is non-incendive or non-sparking. For example, a Class 1, Div 1 area where Group A may be present would be defined as an area where flammable gases or vapors may be present under normal operating conditions. As a guide for Zone 0, this can be defined as over 1,000 hours/year or >10% of the time. The information contained in this article is intended for general information purposes only and is based on information available as of the initial date of publication. Read more in our blogWhich Standards to use for Hazardous Area Classification. The four steps involved in hazardous area classification are: Determine the type of hazard or "class" that might be presentcombustible gas (Class I), combustible dust (Class II), or fibers (Class III). The Zone system of hazardous area classification, defines the probability of the hazardous material, gas, or dust, being present in sufficient quantities that can generate explosive or ignitable mixtures.
Hazardous Area Classification and Control of Ignition Sources - HSE 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).
PDF 1 Classification of Hazardous Areas V00 - Endress+Hauser Class defines the type of explosive or ignitable substances which are present in the atmosphere. Equipment in this category is intended for use in Zone 0 areas (gases) or Zone 20 (dusts), and must ensure a very high level of protection (i.e. Zone 2: An area in which an explosive atmosphere is not likely to occur in normal operation, but if it does . 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. 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. Hazardous Area Classification, Gas Vapours and Dust Groups, Temperature Class | Simple Science Simple Science 8.81K subscribers Join Subscribe 28K views 2 years ago This video explains. Substance properties are specific for the amount of fuel needed to get an explosion when all other conditions are met. Youre phone isnt rated for use in hazardous areas. What are 'Dark Factories,' and Do They Really Exist? EN 16985 concerning spray cabins and powder coating cabins, EN 12779 related to extraction systems for hot sawdust and chips, EN 60079-10 series, 2020 version for gas and dust explosion hazard, NPR 7910 series for gas and dust explosion hazard based on EN 60079-10-1, 2015 version, EN 13617 for fuel dispensers at filling stations. Informational Note No. If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. Home About Us News Hazardous Environment Classifications: NEC vs IEC, Posted March 11, 2019 by springercontrols. For example, a socket outlet labeled EEx'de' might have a case made to EEx 'e' and switches that are made to EEx 'd'. . Carbon monoxide, ether, hydrogen sulfide, . When the concentration of gas or vapor is above the UEL the gas mixture is too rich to burn. Zone 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. Groups A, B, C, and D are for gases (Class I only). July 2021 Zone 2 hazardous areas are typically storage areas but can also be process areas. Area which are not devided into Atex zones, are called non-hazardous area's. Class / Division System In Northerm America, instead of the zone classification system, the Class/Division system is used. Those guidelines address electric wiring, equipment, and systems installed in hazardous (classified) locations and contain specific provisions for the following: wiring methods, wiring connections; conductor insulation, flexible cords, sealing and drainage, transformers, capacitors, switches, circuit breakers, fuses, motor controllers, receptacles, attachment plugs, meters, relays, instruments, resistors, generators, motors, lighting fixtures, storage battery charging equipment, electric cranes, electric hoists and similar equipment, utilization equipment, signaling systems, alarm systems, remote control systems, local loud speaker and communication systems, ventilation piping, live parts, lightning surge protection, and grounding. Safety is ensured in the event of frequently occurring disturbances or equipment faults which normally have to be taken into account. Atmospheres containing combustible flyings. 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. Comparisons between the two systems are not easily accomplished. 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. June 2019 2: This classification includes, Informational Note No. NFPA 70 NEC Zone Classification System The Zone Classification System is offered as an alternative to the Class and Division system. Zone 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. 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. The first thing to understand is that much like the metric vs imperial measuring systems, the United States uses its own methodology which differs from much of the world. Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! 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.