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. The label will always list the class, division and may list the group and temperature code. The last condition for an explosion is the presence of an effective ignition source in the direct contact with the fuel/air mixture. Container Test 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. Zone 1: An area in which an explosive atmosphere is likely to occur in normal operation. Zone 1 2. The overpressure is monitored, maintained and controlled. December 2021 See Figure S-1 for an explanation of this marking. NEC has created an Americanized version of the IEC/CENELEC Zone system in a stand-alone article (Article 505). 6: For further information on electrical systems for hazardous (classified), Informational Note No. Drop Test There are two systems in place, including the traditional North American Division system as well as the alternative Zone system. For specific industries, the specific codes for that industry are important to use. 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. the inside of tank truck or the interior of a dust filter). BATTERY ENERGY STORAGE SYSTEMBESS) Directly adjacent on the label one will find the mark of the listing agency. These hazardous (classified) locations are assigned the following designations: For definitions of these locations, see 1910.399. - 1 2 (Class 1, . Table 1. Electronic equipment, including lighting, needs to be purpose designed for use in hazardous areas to prevent a spark occurring and igniting any flammable substances. Comparison of Zone 2 and Division 2 TABLE 1 - AREA CLASSIFICATIONS Division 1: Where ignitable concentrations can exist all of the time or some . 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. 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. 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. Division defines the probability of the hazardous material being present in an ignitable concentration in the surrounding atmosphere. Hazardous Environment Classifications: NEC vs IEC, IEC (International Electrotechnical Commission), Group E Metal dusts (eg. [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. Upon detection, appropriate action is automatically taken, such as removing power, or providing notification. The Zone Classification System is offered as an alternative to the Class and Division system. 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 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. 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. Safety is ensured in the event of frequently occurring disturbances or equipment faults which normally have to be taken into account. Some manufacturers claim "suitability" or "built-to" hazardous areas in their technical literature, but in effect lack the testing agency's certification and thus unacceptable for the AHJ (Authority Having Jurisdiction) to permit operation of the electrical installation/system. 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. October 2018 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. Area ClassificationThe max surface temp. This page was last edited on 20 January 2023, at 22:32. For example, a socket outlet labeled EEx'de' might have a case made to EEx 'e' and switches that are made to EEx 'd'. Within a working area or installation an ignition can be created by many factors. Within the European Union, these are defined by IEC/EN standards (IEC/EN 60079-10-1 or 2) as directed by ATEX. WHEN YOU NEED THEM. Equipment marked as suitable for Group IIC is also suitable for IIB and IIA. These areas only become hazardous in case of an accident or some unusual operating condition. 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. You can target the Engineering ToolBox by using AdWords Managed Placements. The design of the equipment must ensure protection, even in the event of rare incidents relating to the equipment. Equipment is placed into protection level categories according to manufacture method and suitability for different situations. 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. Dust or other small particles suspended in air can explode. Equipment is pressurised to a positive pressure relative to the surrounding atmosphere with air or an inert gas, thus the surrounding ignitable atmosphere can not come in contact with energized parts of the apparatus. 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: The groups also indicate how much energy is required to ignite the material by energy or thermal effects, with IIA requiring the most energy and IIC the least for zone system gas groups. 1910.307 - Hazardous (classified) locations. 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. Hazardous locations can also be described as those locations where electrical equipment February 2023 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. Hazardous areas are those defined as areas of potential explosion risk due to the presence of flammable gas or vapor. Ignitable concentrations of flammable gases or vapors which are not likely to occur under normal operating conditions and do so only for a short period of time. June 2020 Dry Container Australia and New Zealand use the same IEC-60079 standards (adopted as AS/NZS60079), however the CE mark is not required. 9: For additional information concerning the installation of, Informational Note No. 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. . September 2019 may exist under normal or abnormal conditions because of the presence of flammable gases or vapors, combustible dusts or ignitable fibers or flyings. Informational Note No. No other aspect of safety receives more attention in the form of codes and standards. 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. 2: For the requirements for electrical and electronic. In Europe and the rest of the world - but also more and more in North America - the Zone system is used. 1.1 Scope. 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. Youre phone isnt rated for use in hazardous areas. 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 article covers the requirements for the, Informational Note No. 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. Fundamentally, for an explosion to take place, flammable or explosive gases, vapours, mists or dusts will be present. Many people have heard terms like Class I, Division 2, Group E, or ATEX zone 21 but many of our customers only know what certification they require with little understanding of what they mean, so we thought it would be appropriate to write a blog post to help customers understand the broader implications of these terms. You will find this equipment in paint factories, a warehouse or around a bag dump station. There are several ways of how to perform hazardous area classification, all described in several standards or codes of practise. 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. Terminology for both hazards and protective measures can vary. Group II is for explosive gases (Zone 0, 1 and 2) and Group III is for explosive dusts (Zone 20, 21 and 22). . A material may have a relatively low autoignition temperature yet if its flash-point is above the ambient temperature, then the area may not need to be classified. No representation is made that the information or references are complete or remain current. Both external and internal temperatures are taken into consideration. Category 3 equipment may only be used in zone 2 areas. In general, all types of equipment installed within the hazardous area shall be . Ambient Temperature (-20C to +40C if not marked) Establish Zone Based on "IEC 60079-10". Intrinsic safety designs equipment to operate using minimal energy, insufficient to cause ignition. No long-term contract. Temporary Refuge (TR) Shelter 0. Offshore Living Quarter January 2021 June 2022 Ignition sources can be divided in 13 categories (acc. . An area where combustible dusts or ignitable fibers and flyings are present continuously or for long periods of time. 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". Comments. Two possible classifications are described, in Section 18 (Zones), and Appendix J (Divisions). Class defines the type of explosive or ignitable substances which are present in the atmosphere. The part codes for each SPARTAN variant also differ depending on the level of protection required. 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. Entire Vapour space of storage tank. Areas with possible fire or explosion risks due to explosive atmospheres and/or mixtures - are called hazardous (or classified) locations or areas. The International Electrotechnical Commission publishes the 60079 series of standards[2] which defines a system for classification of locations, as well as categorizing and testing of equipment designed for use in hazardous locations, known as "Ex equipment".