hazardous area classification zone 0, 1, 2

A: When comparing Divisions and Zones, Division 2 is equivalent to Zone 2, but Division 1 is equivalent to either Zone 0 or 1. Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 . June 2022 The NEMA enclosure rating or IP code may also be indicated, but it is usually independent of the Classified Area suitability. For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, conduit fittings, or cable fittings shall be used. Atmospheres containing ethylene, propylene oxide, ethylene oxide, butadiene, cyclopropane, ethyl ether, or gases and vapors of equivalent hazard. January 2022 In Europe the ATEX 114 Directive (2014/34/EU) is applicable to equipment that is used in hazardous area's. The Zones are based on how often the hazard is present rather than upon normal versus abnormal conditions. Figures show that appr. The inductance of the signal bell coils, combined with breaking of contacts by exposed metal surfaces, resulted in sparks, causing an explosion. 7: For further information on application of electrical, Informational Note No. Explosion Hazardous Areas are divided into zones according to risk probabilities. These ways of protection are specified in detail within several IEC standards (IEC 60079 series) for electrical equipment. NFPA 70 NEC Articles 500 through 503 cover the requirements for electrical/electronic equipment and wiring for all voltages in Class I, Divisions 1 and 2; Class II, Divisions 1 and 2; and Class III, Divisions 1 and 2 locations. Arcing electrical equipment in unclassified . Zone 0/20: An area in which an explosive atmosphere is present continuously or for long periods or frequently. 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. A potential few examples of this are: The air space inside a tank of petrol Hazardous areas are those defined as areas of potential explosion risk due to the presence of flammable gas or vapor. All rights reserved. Class II combustible dusts are grouped into one of three (3) groups: E combustible metal dusts, F combustible carbonaceous dusts or G other combustible dusts. That flammable gas or vapor . Copryright 2023 Springer Controls Company . Controls can be fitted to detect dangerous concentrations of hazardous gas, or failure of countermeasures. All areas in the facility that are not Zone 0, Zone 1, or Zone 2 are considered unclassified. Which Standards to use for Hazardous Area Classification. . But when we take a closer look at the graph and table, we can conclude that any explosion, can easily lead to severe damage. In effect it is any method which can be shown to have the required degree of safety in use. Class defines the type of explosive or ignitable substances which are present in the atmosphere. NEGATIVE PRESSURE Hazardous areas are classified into zones based on an assessment of the frequency of the occurrence and duration of an explosive gas atmosphere, as shown in the illustration below. POSITIVE PRESSURE August 2021 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. The relation between that system and de zone classification system is clarified within the following table (only for gases and liquids are displayed, not for dusts and fibers). Offshore Accommodation Module Substances characterization Consequences . Youre phone isnt rated for use in hazardous areas. December 2020 LIFTING TEST 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. 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. 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. In some cases, the hazardous atmosphere is present all the time, or for long periods. 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. Dust or other small particles suspended in air can explode. Sources Choose the right method for Hazardous Area Classification! Ignition sources can be divided in 13 categories (acc. Identifying Zone 0, Zone 1, and Zone 2 Hazardous Areas. 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. Note to paragraph (g)(4) of this section: Low ambient conditions require special consideration. November 2019 When equipment must be placed in a hazardous location, it can be designed to reduce the risk of fire or explosion. 2: For Group IIIC combustible dusts or metal combustible fibers/flyings, there shall only be Zone 20 or 21 locations. the inside of tank truck or the interior of a dust filter). The NEC Zone system was created to harmonize with IEC classification system, and therefore reduce the complexity of management. 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. 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. This can be achieved by blanketing with nitrogen or carbondioxide. 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. Groups E, F, and G are for dusts and flyings (Class II or III). Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 September 2019. | For Gas/Vapor this would be Zone 0. In the US, the independent National Fire Protection Association (NFPA) publishes several relevant standards, and they are often adopted by government agencies. Equipment is placed into protection level categories according to manufacture method and suitability for different situations. 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. 41 gas explosions per year occur within the UK and app. This process is called hazardous area classification. April 2021 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. The IEC standard EN 60079-33 is made public and is expected to become effective soon, so that the normal Ex certification will also be possible for Ex-s, Zone depending upon manufacturer's certification, explosive atmosphere between 10 and 1000 hrs/yr, explosive atmosphere between 1 and 10 hrs/yr, explosive surface between 10 and 1000 hrs/yr, explosive surface between 1 and 10 hrs/yr, Certified and labeled for use in indoor locations rated NEC Class I, Groups A, B, C, and D, Certified and labeled for use in locations rated NEC Class I, Groups A, B, C, and D; both indoors and outdoors, Certified and labeled for use in locations rated NEC Class II, Groups E, F, or G, Explosion protected, Group 2, Category 1, Gas, Type ia, Group 2C gases, Temperature class 4, Type n, non-sparking, Group 2 gases, Temperature class 3, special conditions apply. Substance properties are specific for the amount of fuel needed to get an explosion when all other conditions are met. 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). Zone 1 an area in which an explosive gas-air mixture is likely to occur in normal operating conditions. >> For Gas Vapor this would be Zone 1. 2) MIC (Minimum Igniting Current) Ratio - The ratio of the minimum current required from an inductive spark discharge to ignite the most easily ignitable mixture of a gas or vapor, divided by the minimum current required from an inductive spark discharge to ignite methane under the same test conditions. September 2018 Class I Zone 2 Hazardous Areas. Electrical equipment installed in such locations can provide an ignition source, due to electrical arcing, or high temperatures. (Hazardous Area Classification) . Atmospheres containing non-conductive dust. 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. Division defines the probability of the hazardous material being present in an ignitable concentration in the surrounding atmosphere. Within the European Union, these are defined by IEC/EN standards (IEC/EN 60079-10-1 or 2) as directed by ATEX. 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. 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. 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. Refrigerated If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. Analysers, motors, control boxes, computers, Any arcs or sparks in this equipment has insufficient energy (heat) to ignite a vapour. Recommendat ions. less than 0.45 mm or MIC ratio is less than 0.40. 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. August 2018 Electric equipment depending on the protection techniques described by paragraph (g)(3)(i) of this section may not be suitable for use at temperatures lower than -20 C (-4 F) unless they are approved for use at lower temperatures. These areas only become hazardous in case of an accident or some unusual operating condition. When the concentration of methane is beneath the LEL, an explosion cannot occur, even when an ignition source is present. Increased safety "e" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. Motors, lighting, junction boxes, electronic equipment, This method, being by definition special, has no specific rules. Various regulations use terms such as class, division, zone, and group to differentiate the various hazards. The conduit shall be made wrench tight to prevent sparking when fault current flows through the conduit system and to ensure the explosionproof or flameproof integrity of the conduit system where applicable. This article covers the requirements for the, Informational Note No. Other ignition sources can also be present, like static electricity. Such properties include flame temperature, minimum ignition energy, upper and lower explosive limits, and molecular weight. Temperature Control (1) Zone 0. Have a think about it next time youre filling up! 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: Where gas detection, Informational Note No. ignitable concentrations of dust, fibers, or flyings are present for long periods of time, ignitable concentrations of dust, fibers, or flyings are likely to exist under normal conditions, ignitable concentrations of dust, fibers, or flyings unlikely to exist under normal conditions, Metal dusts, such as magnesium (Division 1 only), Carbonaceous dusts, such as carbon & charcoal, Non-conductive dusts, such as flour, grain, wood & plastic, Ignitible fibers/flyings, such as cotton lint, flax & rayon, Ignitible fibers or flyings, such as cotton lint, flax & rayon. Zone 1 - Explosive atmospheres are likely to occur. For specific industries, the specific codes for that industry are important to use. Classification of locations, testing and listing of equipment, and inspection of installation, is typically overseen by governmental bodies. For equipment with metric threaded entries, such entries shall be identified as being metric, or listed adaptors to permit connection to conduit of NPT-threaded fittings shall be provided with the equipment. NEC has created an Americanized version of the IEC/CENELEC Zone system in a stand-alone article (Article 505). Zone 1 is an area that is classified 'as a place in which an explosive atmosphere consisting of a mixture with air or flammable substances in the form of gas, vapours and mists is likely to occur occasionally during normal operation', whereas Zone 2 is an area that is classified 'as a place in which an explosive atmosphere consisting of a mixture . But beside electrical equipment also mechanical equipment must be Ex certified, e.g. Equipment that is listed for a Zone 0 location may be installed in a Zone 1 or Zone 2 location of the same gas or vapor. See Figure S-1 for an explanation of this marking. These generally give rise to areas classied as Zones 0, 1, and 2 respectively. When the concentration of gas or vapor is beneath the LEL the gas mixture is too lean to burn. June 2020 Zone type (0/1/2/ 20/21/ 22) Zone extent. The flash point determines if an area needs to be classified. WELDING INSPECTION - Zone 0: An area where an explosive gas-air mixture is continuously present or present for long time (continuous hazard, whose estimated duration is higher than 1000 hours/year) - Zone 1: An area where an explosive gas-air mixture is likely to occur during normal . January 2023 As a guide for Zone 0, this can be defined as over 1000 hours/year or >10% of the time. FEA Container Accessories Q: Can I use a piece of equipment approved for use in a Division 1 hazardous location in a Division 2 hazardous location? 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. July 2019 In electrical and safety engineering hazardous locations HazLoc pronounced hazlk are places where fire or explosion hazards may exist. National Electric Code 2020 edition National Fire Protection Association. In the US, the National Electrical Manufacturers Association (NEMA) defines standards for enclosure types for a variety of applications. A Zone 0 location is a location in which one of the following . A list must be drawn up of every explosive material that is on the refinery or chemical complex and included in the site plan of the classified areas. Informational Note No. November 2020 BATTERY ENERGY STORAGE SYSTEMBESS) . Requirements for good HAC Drawings and Plans. Equipment construction is such that it can withstand an internal explosion and provide relief of the external pressure via flamegap(s) such as the labyrinth created by threaded fittings or machined flanges. Some other standards have more quantitative methods which require more knowledge of the plant, an example is the IEC standard 60079-10-1. October 2018 Zone 0 describes an area in which a combustible gas will be present continuously while zone 20 describes an area in which combustible dust will be present continuously (the '2' in 'zone 20' indicates dust as opposed to gas).