Pressurised Container Equipment marked as suitable for Group IIC is also suitable for IIB and IIA. TLS OFFSHORE CONTAINER * Zone 1 a location in which explosive gas atmospheres are likely to occur during normal operation, or which is adjacent to a Zone 0 location. This value of this LOC differs per substance and depends also on the inert gas for achieving a low oxygen concentration. ), Group F Carbon-based (eg. October 2019 . Quick Tips #124.1. Ex s is a coding referenced in IEC 60079-0. But every hazardous area is different and each has specific requirements depending on the nature of the atmosphere and the elements that are present. August 2022 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. In instances of areas within the same facility classified separately, Class I, Zone 2 locations may abut, but not overlap, Class I, Division 2 locations. >> For Gas/Vapor this would be Zone 0. Informational Note: For further information regarding classification and ventilation of areas involving closed-circuit ammonia refrigeration systems, see ANSI/IIAR 2-2014. Beside the Lower Explosion Limit, each substance also has an Upper Explosion Limit (UEL). An oversimplification of this example is shown in Table 1. October 2020 | For Dust this would be Zone 21. 14 4. 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. Area's are divided into zones. In other cases, the atmosphere is normally non-hazardous, but a dangerous concentration can be reasonably foreseensuch as operator error or equipment failure. Standards and regulations exist to identify such locations, classify the hazards, and design equipment for safe use in such locations. When comparing Divisions and Zones, Division 2 is equivalent to Zone 2, but Division 1 is equivalent to either Zone 0 or 1. Hazards in this group gas can be ignited very easily indeed. 5: For further information on ventilation, see NFPA 30-2018, Informational Note No. In the US, the National Electrical Manufacturers Association (NEMA) defines standards for enclosure types for a variety of applications. [1] NEC article 500 describes the NEC Division classification system, while articles 505 and 506 describe the NEC Zone classification system. Electronic equipment, including lighting, needs to be purpose designed for use in hazardous areas to prevent a spark occurring and igniting any flammable substances. This article covers the requirements for the, Informational Note No. WATER TIGHTNESS To prevent explosions from happening in harsh environments whereby flammable gases or combustible dusts are present directives and guidelines are put in place to protect both the public, workforce, and environment. What are 'Dark Factories,' and Do They Really Exist? All rights reserved. So it is quite obvious that explosions should be prevented as much as possible and still work has to be done to achieve this. NFPA 70, the National Electrical Code (NEC), defines area classification and installation principles. >> NEC: Class I, Division 2, Group D. | IEC: Zone 2, Group II. IEC 60079-10-1 covers classification of explosive gas atmospheres, and IEC 60079-10-2 explosive dust. CUTTING SKIPS In the United Kingdom, Sira and Baseefa are the most well known such bodies. RP 505 is referred to as the zone system. (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. It may exist because of repair, maintenance operations, or leakage. The Class/Division/Group system is based on Article 500 of the National Electrical Code (NEC) where. gas, vapours, mists and dusts). Since this fuel can only combust in the presence of oxygen, enough oxygen must be available for the rapid combustion to take place. Zone 0/20: An area in which an explosive atmosphere is present continuously or for long periods or frequently. No hidden fees. What Are All Those Gadgets On A Multitool? But when we take a closer look at the graph and table, we can conclude that any explosion, can easily lead to severe damage. The Zone system has three levels of hazard for gas or dust. The Occupational Safety and Health Administration (OSHA) has adopted these hazardous classifications and all except Groups are defined in 29 Code of Federal Register (CFR) 1910.399. Zone 1 fittings are supplied as silver, Zone 2 as dark grey and industrial fittings as white. Carbon monoxide, ether, hydrogen sulfide, . Substances characterization Consequences . Offshore Accommodation Module This rapid expansion of volume is caused by the combustion of a fuel, like e.g. 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. Zone 1: An area in which an explosive atmosphere is likely to occur in normal operation. An explosion is a rapid expansion in volume associated with an extremely vigorous outward release of energy, usually with the generation of high temperatures and release of high-pressure gases (wikipedia (https://en.wikipedia.org/wiki/Explosion). Oil Immersion "o" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. It is an Americanized version of the International Electrochemical Commissions (IEC) Zone system which maintains the NEC wiring methods and protection techniques. Zone defines thegeneral nature if it is a gas or dust and theprobabilityof hazardous material being present in an ignitable concentration in the surrounding atmosphere. 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. 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. Temporary Refuge (TR) Shelter 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. 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. Zone 1 . Informational Note No. It is created based on input from the Process Flow Diagrams, Piping & Instrumentation Diagrams and the Equipment Location Plan . Within the European Union, these are defined by IEC/EN standards (IEC/EN 60079-10-1 or 2) as directed by ATEX. Zone 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. Shown below is a summary of the applicable NEC Articles to reference to ensure the proper requirements are applied. In the US, the independent National Fire Protection Association (NFPA) publishes several relevant standards, and they are often adopted by government agencies. NFPA 70 NEC establishes area classifications based on Classes, Divisions and Groups that when combined delineate the hazardous conditions of a specific area. Various regulations use terms such as class, division, zone, and group to differentiate the various hazards. 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. 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] Temperature classification, except for intrinsically safe apparatus. It is essential to know which zone you are working in, so that you can specify the most appropriate equipment. In some cases, it must be certified as meeting that standard. Also included in the marking are the manufacturers name or trademark and address, the apparatus type, name and serial number, year of manufacture and any special conditions of use. Guidance on assessment of hazards is given in NFPA497 (explosive gas) and NFPA499 (dust). Wide known is that al electrical equipment within hazardous areas must be Ex certified for use in the appropriate hazardous area (zone or class/division). Cookies are only used in the browser to improve user experience. 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. Have a think about it next time youre filling up! Group defines the type of the hazardous material in the surrounding atmosphere. Explosion-proofing designs equipment to contain ignition hazards, prevent entry of hazardous substances, and, contain any fire or explosion that could occur. The part codes for each SPARTAN variant also differ depending on the level of protection required. 29 CFR 1910.307 Hazardous (classified) Locations
The housing may be strong enough to contain and cool any combustion gases produced internally. Locations are thus classified by type and risk of release of gas, vapor, or dust. Methane has a UEL of 17 vol%, which means when the concentration of methane in air is above the 17 vol% an explosion cannot occur even when an ignition source is present. In order to understand hazardous area classification it is important to understand which factors contribute to the occurrence of an explosion. For specific industries, the specific codes for that industry are important to use. Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! Although OSHA does not provide a definition of group classifications in 29 CFR 1910.307 or 399 they do provide a note under 29 CFR 1910.307(c)(1) that states: NFPA 70, the National Electrical Code, lists or defines hazardous gases, vapors, and dusts by Groups characterized by their ignitable or combustible properties. To meet OSHAs marking requirement, the marking must include the hazardous group the equipment is approved to operate in. HAZARDOUS VS. 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. So a zone 0 is the most hazardous zone and a zone 2 is a less hazardous zone. Employers may use the zone classification system as an alternative to the division classification system for electric and electronic equipment and wiring for all voltage in Class I, Zone 0, Zone 1, and Zone 2 hazardous (classified) locations where fire or explosion hazards may exist due to flammable gases, vapors, or liquids. 6: For further information on electrical systems for hazardous (classified), Informational Note No. . 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). It is always balancing between not defining such areas too large (with highly costs for prevention of ignition sources) or too small (unsafe situations). The term equipment is applied both for fixed equipment and mobile equipment that are operated in such area. Definition of hazardous area zones (AS/NZS 60079.10): Zone 0 These generally give rise to areas classied as Zones 0, 1, and 2 respectively. 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. Vertical. Class I, Zone 0 or Zone 1 locations may not abut Class I, Division 1 or Division 2 locations. 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. The overpressure is monitored, maintained and controlled. Refrigerated Equipment should be tested to ensure that it does not exceed 80%[according to whom?] Refer to Fig.3 which shows the hazardous area zone classification based on hazardous gas release grade. Recommendat ions. Zone 0, 1 2 . Flour, wood/sawdust, plastic dust), IIC Conductive dusts (eg. Hazardous area classification is a rigorous method of determining where an explosive environment may be present. 2: For Group IIIC combustible dusts or metal combustible fibers/flyings, there shall only be Zone 20 or 21 locations. Zone 2: An area in which an explosive atmosphere is not likely to occur in normal operation, but if it does . Zone 1 - Explosive atmospheres are likely to occur. Flammable liquids with a high flash point are less hazardous than liquids Equipment shall be marked to show the class, group, and operating temperature or temperature range, based on operation in a 40-degree C ambient, for which it is approved. Upon detection, appropriate action is automatically taken, such as removing power, or providing notification. This means that the electrical equipment is safe for use within these area by applying special protection strategies. SPARTANs Zone 1 part code begins SPX, Zone 2 SPZ and industrial products having a SPI prefix. The most standards and codes of practise for Hazardous Area Classification describe typical installations and work environments and their hazardous areas. 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. Specific types of protection being used will also be marked. may exist under normal or abnormal conditions because of the presence of flammable gases or vapors, combustible dusts or ignitable fibers or flyings. 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: . 4: For further information on protection against static electricity and lightning hazards in hazardous (classified). The equipment housing may be sealed to prevent entry of flammable gas or dust into the interior. 3: For further information on the classification of, Informational Note No. August 2020 Feedback From Clients 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. Other ignition sources can also be present, like static electricity. Informational Note No. 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! 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. 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. Arc-producing elements can be isolated from the atmosphere, by encapsulation in, Heat-producing elements can be designed to limit their maximum temperature below the. A room with a propane gas installation will typically be classified with the. You will find this equipment in paint factories, a warehouse or around a bag dump station. Well recognized and clear IEC Standard IEC 60079-10-2:2015 Hazardous Area Classification for explosive dusts Significant influence on spending's for safety . 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. No other aspect of safety receives more attention in the form of codes and standards. Category 1 equipment may be used in zone 0, zone 1 or zone 2 areas. 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). 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). The following content is only related to flammable substances and not to pyrotechnic substances or other instable substances, among those who can decompose. The NEMA enclosure rating or IP code may also be indicated, but it is usually independent of the Classified Area suitability. We don't collect information from our users. 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. Equipment is placed into protection level categories according to manufacture method and suitability for different situations. Often an area classification plan view is provided to identify equipment ratings and installation techniques to be used for each classified area. SEWAGE TREATMENT lk) are places where fire or explosion hazards may exist. ". 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. This concentration is substance specific and lies normally somewhere between the LEL and UEL. 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. 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. Substance properties are specific for the amount of fuel needed to get an explosion when all other conditions are met. Offshore Living Quarter Safe for the hazardous (classified) location. This is also one of the first steps when composing an Explosion Protection Document. 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. 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). Zone 2 Explosive Mixtures not likely to occur /occur short duration in normal operation (lt10 Hrs/ Yr). THE CURRENT STANDARD . Home About Us News Hazardous Environment Classifications: NEC vs IEC, Posted March 11, 2019 by springercontrols. Ignitable concentrations of flammable gases or vapors which are present continuously or for long periods of time. Atmospheres containing acetylene, hydrogen, carbon disulphide or gases and vapors of equivalent hazard. eg Production Area, area surrounding zone 0. Zone 22 Zone 21 Zone20 A hazardous atmosphere formed by dust cloud in air is not likely to occur in . A hazardous area can be defined as any location where there is risk of an explosion. Fundamentally, for an explosion to take place, flammable or explosive gases, vapours, mists or dusts will be present. These would be then labeled with each of the individual methods. 7: For further information on application of electrical, Informational Note No. area in which an explosive gas atmosphere is not likely to occur in normal operation, but, if it does occur, will exist for a short period only (less than 0,1% of the time), Window breakage, cracks plaster, light damage to buildings, Collapse of wood or asbestos siding of homes, Collapse of walls made of concrete blocks, Reinforced concrete structures severely damaged, Flames and hot gases (including hot particles), Mechanically generated impact, friction and abrasion, Stray electric currents, cathodic corrosion protection, Radio frequency (RF) electromagnetic waves from 10, Exothermic reactions, including self-ignition of dusts, EI 15 Energy Institute 15, mostly for on- and offshore oil and gas applications. 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. 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. The types of protection are subdivided into several sub classes, linked to EPL: ma and mb, px, py and pz, ia, ib and ic. In Europe the ATEX 114 Directive (2014/34/EU) is applicable to equipment that is used in hazardous area's. So the following conditions must be met for an explosion to occur: Represented by the following explosion triangle. The prevention of explosions in working environments is in most countries regulated in national laws and directives. 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. Reefer Container September 2018 Informational Note No. 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. December 2022 January 2021 The hazardous area classification system determines required protection techniques and methods for electrical installations in the location. In an industrial plant, such as a refinery or chemical plant, handling of large quantities of flammable liquids and gases creates a risk of exposure. These areas are in North America (United States and Canada) historically classified with the Class/Division system. . 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. If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. class correct, Motors, lighting, junction boxes, electronics, Equipment is very robust and components are made to a high quality, Equipment components are completely submerged in oil, Equipment components are completely covered with a layer of sand, powder or quartz, Equipment components of the equipment are usually encased in a resin type material. In 29 CFR 1910.307(c)(2)(ii), OSHA requires all equipment used in a hazardous location to be marked with the class, group and operating temperature or temperature range for which it is approved. February 2021 June 2019 The codes and standards used in this process provide guidance for selecting,. In many industrial, commercial, and scientific settings, the presence of such an atmosphere is a common, or at least commonly possible, occurrence. And there are three corresponding zones for dust: Zone 20, Zone 21 and Zone 22. Horizontal. 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. So for an explosion there must be enough fuel. But first, we must consider what is likely to cause an explosion in the first place. 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. In this article 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. 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 The design of the equipment must ensure protection, even in the event of rare incidents relating to the equipment. 1: As a guide in determining when flammable gases or vapors are present continuously or for long periods of time, refer to ANSI/API RP 505-2018, Informational Note No. There are two sets of Zones: Zones 0 thru 2 are used for gases, vapors, and mists, and Zones 20 thru 22 are . Ways to ensure this level of safety are non-arcing design and limitation of the temperature of the equipment.