Offshore Workshop Container 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). Controls can be fitted to detect dangerous concentrations of hazardous gas, or failure of countermeasures. The NEC Zone system was created to harmonize with IEC classification system, and therefore reduce the complexity of management. But beside electrical equipment also mechanical equipment must be Ex certified, e.g. Zones compares to classes and divisions in the Class/Division system. Such properties include flame temperature, minimum ignition energy, upper and lower explosive limits, and molecular weight. ADNOC No. This article covers the requirements for the, Informational Note No. Informational Note: For further information regarding classification and ventilation of areas involving closed-circuit ammonia refrigeration systems, see ANSI/IIAR 2-2014. 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. d : HA - ha ea OA - oa Area classification - Divisions vs. zones Continuous hazard Intermittent hazard Hazard under abnormal conditions Zone 0 Zone 1 Zone 2 Division 1 Division 1 Division 2 Hazardous locations - CEC classifications Class I In general, all types of equipment installed within the hazardous area shall be . Equipment provided with threaded entries for field wiring connection shall be installed in accordance with paragraph (g)(2)(iv)(A) or (g)(2)(iv)(B) of this section. Equipment shall be approved not only for the class of location, but also for the ignitable or combustible properties of the specific gas, vapor, dust, or fiber that will be present. Zone 2 is a place in which an explosive atmosphere is not likely to occur in normal operation but, if it does occur, will persist for a short period only. Type of protection "n" -- This protection technique is permitted for equipment in the Class I, Zone 2 locations for which it is approved. Ex LIGHTER-THAN-AIR GASES & VAPOURS Vapour density of 0.75 is considered as the boundary between lighter and heavier gases / vapours as a safety measure HA of a leak source located in air Source of hazard 4.5 m. 8.0 m R 4.5 m H Have a think about it next time youre filling up! Powder Filling "q" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. 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. Zone 22 Zone 21 Zone20 A hazardous atmosphere formed by dust cloud in air is not likely to occur in . Category 2 equipment may be used in zone 1 or zone 2 areas. These ways of protection are specified in detail within several IEC standards (IEC 60079 series) for electrical equipment. This is also one of the first steps when composing an Explosion Protection Document. Safety is ensured in the event of frequently occurring disturbances or equipment faults which normally have to be taken into account. . 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. This concentration is substance specific and lies normally somewhere between the LEL and UEL. Beside the Lower Explosion Limit, each substance also has an Upper Explosion Limit (UEL). For example the EI 15 and API 500/505 describe specific installations and several conditions for the oil and gas industry. API 500/505 mostly for onshore and offshore oil and gas applications. Drop Test 2: For Group IIIC combustible dusts or metal combustible fibers/flyings, there shall only be Zone 20 or 21 locations. The plan may contain the list of chemicals with their group and temperature rating. Zone 1 is an area in which an explosive atmosphere is likely to occur occasionally in normal operation. In many industrial, commercial, and scientific settings, the presence of such an atmosphere is a common, or at least commonly possible, occurrence. October 2022 With the advent of electric power, electricity was introduced into coal mines for signaling, illumination, and motors. 0,1 or 2: II B: I: 1 or 2: C: Acetone Benzene Butane Hexane . Since this fuel can only combust in the presence of oxygen, enough oxygen must be available for the rapid combustion to take place. A60 . Read more in our blogWhich Standards to use for Hazardous Area Classification. 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. Raytec do not currently offer any lighting solutions for Zone 0. This equipment is intended for use in Zone 1 (gases) or Zone 21 (dusts). The process of determining the type and size of hazardous locations is called classification. Container Standards Click on the zone to learn more about the classification according to IEC 60079-10 standards. See Figure S-1 for an explanation of this marking. Determined to be none of the above. The Zone Classification System is offered as an alternative to the Class and Division system. Then, the level of risk of an explosion is based on the frequency and duration of the occurrence of an explosive atmosphere. The equipment housing may be sealed to prevent entry of flammable gas or dust into the interior. The specific hazardous materials within each group and their automatic ignition temperatures can be found in Article 500 of the National Electrical Code and in NFPA 497. In other cases, the atmosphere is normally non-hazardous, but a dangerous concentration can be reasonably foreseensuch as operator error or equipment failure. 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. See below for further details: Division system sample marking Hazardous Area Classification is a study, in which is assessed, at witch locations of a plant, factory or company, high concentrations of flammable gases are present or can be released, in order to create an explosion hazard. according to ISO standard 80079 series. Workshop Container, Intelligent pressurised container | MUD logging cabin, Battery energy storage system (BESS) container, Laboratory container | workshop container | Equipment containers, Temporary refuge shelter | Toxic gas refuge | Safe haven, Offshore accommodation cabin | office container, Reefer container | Refrigerated container, Intelligent waste water treatment container, IDENTIFYING ZONE 0, ZONE 1, AND ZONE 2 HAZARDOUS AREAS, Temporary refuge (TR) shelter, toxic gas refuge (TGR), Containerised waste water treatment plant. November 2020 But when we take a closer look at the graph and table, we can conclude that any explosion, can easily lead to severe damage. Ignitable concentrations of flammable gases or vapors which are likely to occur under normal operating conditions. There are two systems in place, including the traditional North American Division system as well as the alternative Zone system. 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. A: Yes. Q: Are Divisions and Zones equivalent to one another? Standards and regulations exist to identify such locations, classify the hazards, and design equipment for safe use in such locations. . Comparison of Zone 2 and Division 2 TABLE 1 - AREA CLASSIFICATIONS Division 1: Where ignitable concentrations can exist all of the time or some . Choose the right method for Hazardous Area Classification! Adapters shall be used for connection to conduit or NPT-threaded fittings. 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. Flammable liquids with a high flash point are less hazardous than liquids Reefer Container Well recognized and clear IEC Standard IEC 60079-10-2:2015 Hazardous Area Classification for explosive dusts Significant influence on spending's for safety . 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. Terminology for both hazards and protective measures can vary. 6: For further information on electrical systems for hazardous (classified), Informational Note No. Which Standards to use for Hazardous Area Classification. Informational Note No. 3: For further information on the classification of, Informational Note No. . Is intended for us in Zone 2 (gases) or Zone 22 (dusts). Ambient Temperature (-20C to +40C if not marked) Establish Zone Based on "IEC 60079-10". Class 1/Div 2 ATEX Zone 2 Computers. Substance properties are specific for the amount of fuel needed to get an explosion when all other conditions are met. There are several ways of how to perform hazardous area classification, all described in several standards or codes of practise. Flammable atmosphere expected to be present inside the storage tank continuously, hence it has been classified as zone 0. (between 0,1 and 10% of the time). Atmospheres containing combustible flyings. 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). 11: For information on electric skin effect trace heating for hazardous (classified), Informational Note No. 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. >> NEC: Class I, Division 2, Group D. | IEC: Zone 2, Group II. Independent test housesNotified Bodiesare established in most European countries, and a certificate from any of these will be accepted across the EU. 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. Dn 2 - a Ce d e r . 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. ESS Container February 2022 These areas only become hazardous in case of an accident or some unusual operating condition. Atmosphere containing flammable gas, flammable liquid produced vapor, or combustible liquid produced vapor mixed with air that may burn or explode, having either a MESG value greater than 0.75 mm or a MIC ratio greater than 0.80 - such as gasoline, acetone, ammonia, benzene, butane, ethanol, hexane, methanol, methane, vinyl chloride, natural gas, naphtha, propane or gases of equivalent hazard. Dust or other small particles suspended in air can explode. Feedback From Clients October 2020 This means that the electrical equipment is safe for use within these area by applying special protection strategies. ethanol, methane or hydrogen. Explosions can cause significant damage along with severe injury or worse loss of life. June 2020 Ways to ensure this level of safety are non-arcing design and limitation of the temperature of the equipment. 1: For examples of area classification drawings, see ANSI/API RP 505-2018, Informational Note No. You can target the Engineering ToolBox by using AdWords Managed Placements. That is why the use of mobile phones on petrol forecourts are banned. Copryright 2023 Springer Controls Company . Equipment that is listed for a Zone 1 location may be installed in a Zone 2 location of the same gas or vapor. In the IEC standards hazardous areas are classified into zones based upon the frequency and duration of an explosive atmosphere. 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. Gases, Vapors and Mists. hazardous areas as the following: An area where a potential hazard (e.g., a fire, an explosion, etc.) Equipment can be designed or modified for safe operation in hazardous locations. 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. coal and charcoal), Group G Nonconductive dusts (eg. 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. May 2021 When the concentration of gas or vapor is above the UEL the gas mixture is too rich to burn. 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). 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. 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.