hazardous area classification zone 0, 1, 2

Much early equipment having Ex s protection was designed with encapsulation and this has now been incorporated into IEC 60079-18 [Ex m]. SPARTANs Zone 1 part code begins SPX, Zone 2 SPZ and industrial products having a SPI prefix. 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 types of protection are subdivided into several sub classes, linked to EPL: ma and mb, px, py and pz, ia, ib and ic. We don't collect information from our users. 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: Copryright 2023 Springer Controls Company . Atmospheres containing acetylene, hydrogen, carbon disulphide or gases and vapors of equivalent hazard. The part codes for each SPARTAN variant also differ depending on the level of protection required. 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. 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. Shown below is a summary of the applicable NEC Articles to reference to ensure the proper requirements are applied. 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] 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. Only emails and answers are saved in our archive. October 2018 NEGATIVE PRESSURE Q: Are Divisions and Zones equivalent to one another? 1910.307 (g) (2) 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. WATER TIGHTNESS As a guide for Zone 0, this can be defined as over 1000 hours/year or >10% of the time. Independent test housesNotified Bodiesare established in most European countries, and a certificate from any of these will be accepted across the EU. 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". Gases, Vapors and Mists. Encapsulation "m" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. Often an area classification plan view is provided to identify equipment ratings and installation techniques to be used for each classified area. The Hazardous Area Classification presents in this guide is based on the following items as reference: API: API RP 505 Recommended Practice for Classification of Locations for Electrical. 1994-2020, W.W. Grainger, Inc. All Rights Reserved. July 2021 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. There are several ways of how to perform hazardous area classification, all described in several standards or codes of practise. Group II is for explosive gases (Zone 0, 1 and 2) and Group III is for explosive dusts (Zone 20, 21 and 22). 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 But beside electrical equipment also mechanical equipment must be Ex certified, e.g. Typical gas hazards are from hydrocarbon compounds, but hydrogen and ammonia are also common industrial gases that are flammable. Not only are hazardous areas classified by Class (nature of the hazardous material,) and Division . Table 1. This article covers the requirements for the, Informational Note No. Zone 1 2. It is obvious to use those standards within these industries. coal and charcoal), Group G Nonconductive dusts (eg. Zone 0: flammable atmosphere highly likely to be present - may be present for long periods or even continuously . May 2021 >> NEC: Class I, Division 2, Group D. | IEC: Zone 2, Group II. 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. A60 Hazardous areas are classified into 3 zones based upon the frequency of the occurrence and duration of an explosive gas atmosphere, as follows: Zone 0 Area in which an explosive gas atmosphere is present continuously or for long periods or frequently. October 2021 Class defines the type of explosive or ignitable substances which are present in the atmosphere. MCC Shelter This is because Zone 0 usually classifies areas for gas storage or containment, and any lighting required would be used on a small and portable basis for visual inspection, e.g. August 2020 Coal mines, grain mills, elevators, and similar facilities likewise present the risk of a clouds of dust. Enclosures can be pressurized with clean air or inert gas, displacing any hazardous substance. Comparison of Zone 2 and Division 2 TABLE 1 - AREA CLASSIFICATIONS Division 1: Where ignitable concentrations can exist all of the time or some . 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. In some cases, it must be certified as meeting that standard. This value of this LOC differs per substance and depends also on the inert gas for achieving a low oxygen concentration. September 2022 . 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. In other cases, the atmosphere is normally non-hazardous, but a dangerous concentration can be reasonably foreseensuch as operator error or equipment failure. The housing may be strong enough to contain and cool any combustion gases produced internally. (1) Zone 0. You will find these zones at the manifold of a tank truck or the interior of a silo. International Electrotechnical Committee (IEC) Hazardous Area Classification. July 2022 Accommodation Cabin In recent years also the EPL is specified for several kinds of protection. Motors, lighting, junction boxes, electronic equipment, This method, being by definition special, has no specific rules. Standards for electrical installations have been established and are governed by a variety of organizations throughout the world to ensure safe electrical systems in hazardous locations. Then, the level of risk of an explosion is based on the frequency and duration of the occurrence of an explosive atmosphere. If equipment is marked, for example, Ex e II T4 then it is suitable for all subgroups IIA, IIB and IIC. 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. Intrinsic safety -- This protection technique is permitted for equipment in the Class I, Zone 0 or Zone 1 locations for which it is approved. Electrical equipment installed in such locations can provide an ignition source, due to electrical arcing, or high temperatures. This is presented by the Lower Explosion Limit (LEL) of a substance. area in which an explosive gas atmosphere is likely to occur occasionally in normal operation. 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. But first, we must consider what is likely to cause an explosion in the first place. Dust or other small particles suspended in air can explode. Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! This rapid expansion of volume is caused by the combustion of a fuel, like e.g. These would be then labeled with each of the individual methods. A potential few examples of this are: The air space inside a tank of petrol Class II, Div 2 Class III, Div 1 nR 3G Zone 2 Gc Class III, Div 2 Pressurised Room px 60079-13 2G Zone 1 Gb Zone 21 Db 2D Pressurised Room FM3611 NFPA 496 Class I, Div 1 Class I, Div 2 Class II, Div 1 Class II, Div 2 py 2G Zone 1 Gb pz 3G Zone 2 Gc Zone 22 Dc 3D pv Non-hazardous Gb/GC Optical Radiation op sh 60079-28 1G Zone 0 Ga Zone 20 Da 1D . Determining the Class, Division and Group or Zone and Group is critical to correctly applying the requirements for a given hazardous location. The colour of the luminaire body indicates the level of protection. Electronic equipment, including lighting, needs to be purpose designed for use in hazardous areas to prevent a spark occurring and igniting any flammable substances. Zone 2 Explosive Mixtures not likely to occur /occur short duration in normal operation (lt10 Hrs/ Yr). 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. A spark or high heat must also be present. the inside of tank truck or the interior of a dust filter). Zone 0, 1 2 . >> NEC: Class II, Division 1, Group F. | IEC: Zone 20, Group IIC. Hazardous Environment Classifications: NEC vs IEC, IEC (International Electrotechnical Commission), Group E Metal dusts (eg. All threaded conduit shall be threaded with an NPT (National (American) Standard Pipe Taper) standard conduit cutting die that provides -in. | For Gas/Vapor this would be Zone 0. The surface of a high pressure steam pipe may be above the autoignition temperature of some fuel-air mixtures. * Zone 2 a . . Zone 0 Zone 1 Zone 2 Fluid Occurrence of explosive atmosphere Gas mixtures Dust mixtures Not likely to occur or only for short period Zone 2 Zone 22 . You can target the Engineering ToolBox by using AdWords Managed Placements. Each chemical gas or vapour used in industry is classified into a gas group. 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. Area's are divided into zones. These areas are in North America (United States and Canada) historically classified with the Class/Division system. All rights reserved. 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. Marking "EEx d" in Accordance with EN 50 0 14 and 50 018 . Various regulations use terms such as class, division, zone, and group to differentiate the various hazards. There are two sets of Zones: Zones 0 thru 2 are used for gases, vapors, and mists, and Zones 20 thru 22 are . This was accompanied by electrically-initiated explosions of flammable gas such as fire damp (methane) and suspended coal dust. 10: For information on electrical resistance trace heating for hazardous (classified), Informational Note No. These areas only become hazardous in case of an accident or some unusual operating condition. September 2018 Flour, wood/sawdust, plastic dust), IIC Conductive dusts (eg. 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. Other ignition sources can also be present, like static electricity. WHEN YOU NEED THEM. The key difference between Divisions and Zones relate to terminations. No hidden fees. Equipment should be tested to ensure that it does not exceed 80%[according to whom?] Recommendat ions. . 1. Analysers, motors, control boxes, computers, Any arcs or sparks in this equipment has insufficient energy (heat) to ignite a vapour. Hazardous locations can also be described as those locations where electrical equipment 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. No. April 2021 ), Group F Carbon-based (eg. November 2020 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. Two possible classifications are described, in Section 18 (Zones), and Appendix J (Divisions). These generally give rise to areas classied as Zones 0, 1, and 2 respectively. Hazardous areas are classified into zones based on an assessment of the frequency of the occurrence and duration of an explosive gas atmosphere, as follows: Zone 0: An area in which an. Guidance on assessment of hazards is given in NFPA497 (explosive gas) and NFPA499 (dust). NFPA 70, the National Electrical Code (NEC), defines area classification and installation principles. Arcing electrical equipment in unclassified . Comparison of Zones and Divisions. Hazardous Areas - North America Classification, international method of area classification, Protection Techniques for Hazardous Areas - North America, Hazardous because combustible or conductive, Atmosphere containing combustible metal dusts, including. Intrinsic safety designs equipment to operate using minimal energy, insufficient to cause ignition. 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. 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). Which Standards to use for Hazardous Area Classification. 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. 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. FEA These are typically process areas where gases are more likely to be present. Several protection strategies exist. Increased safety "e" -- This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. 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. No representation is made that the information or references are complete or remain current. Determined to be none of the above. These hazardous (classified) locations are assigned the following designations: For definitions of these locations, see 1910.399. The value is represented is volume percentage of oxygen. Ex s is a coding referenced in IEC 60079-0. September 2019 In many industrial, commercial, and scientific settings, the presence of such an atmosphere is a common, or at least commonly possible, occurrence. All areas in the facility that are not Zone 0, Zone 1, or Zone 2 are considered unclassified. | For Dust this would be Zone 22. Offshore Accommodation Module For gases, vapours and mists the zone classifications are recognised as Zone 0, Zone 1 and Zone 2 areas. 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. For liquids, gases and vapours: Zone 0, Zone 1 and Zone 2. If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. No long-term contract. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. Is intended for us in Zone 2 (gases) or Zone 22 (dusts). So for an explosion there must be enough fuel. 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. A Zone 0 location is a location in which one of the following . Vertical. April 2022 However, at low ambient temperatures, flammable concentrations of vapors may not exist in a location classified Class I, Zone 0, 1, or 2 at normal ambient temperature. The equipment group . 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. October 2022 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. |MWD/LWD Cabin FREEZER Zone 1 fittings are supplied as silver, Zone 2 as dark grey and industrial fittings as white. What Are All Those Gadgets On A Multitool? Hazardous area classification is a rigorous method of determining where an explosive environment may be present. Category 3 equipment may only be used in zone 2 areas. Sources January 2022 Horizontal. In Europe the label must show the CE mark and the code number of the certifying/notified body). Informational Note: For further information regarding classification and ventilation of areas involving closed-circuit ammonia refrigeration systems, see ANSI/IIAR 2-2014. October 2019 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. The American Petroleum Institute publishes analogous standards in RP500 andRP505. The overpressure is monitored, maintained and controlled. 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. Entire Vapour space of storage tank. Choose the right method for Hazardous Area Classification! of the autoignition temperature of the hazardous atmosphere. Equipment approved for Class I, Division 1 or Class 1, Division 2 shall, in addition to being marked in accordance with (c)(2)(ii), be marked with the following: Class I, Zone 1 or Class I, Zone 2 (as applicable); Applicable gas classification groups; and. February 2021 Equipment approved for use in Class I hazardous locations cannot be used in Class II hazardous locations. June 2019 In the US, the National Electrical Manufacturers Association (NEMA) defines standards for enclosure types for a variety of applications. 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. ". . 3: For further information on the classification of, Informational Note No. Explosion protection must be ensured during normal operation. Figures show that appr. In the IEC standards hazardous areas are classified into zones based upon the frequency and duration of an explosive atmosphere. Zone 0 is reserved for those areas continuously hazardous (e.g., inside a vented fuel tank), so other Division 1 areas would be classified as Zone 1. NFPA 70 NEC Articles 505 and 506 cover the requirements for the Americanized Zone classification system as an alternative to the Class and Division classification system. Then, the level of risk of an explosion is based on the frequency and duration of the occurrence of an explosive atmosphere. This page was last edited on 20 January 2023, at 22:32. 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. Zone 0, 1, and 2 locations shall include those specified in 505.5 (B) (1), (B) (2), and (B) (3). IEC 60079-10-1 covers classification of explosive gas atmospheres, and IEC 60079-10-2 explosive dust. . National Electric Code 2020 edition National Fire Protection Association. Get more great content like this sent to your inbox. 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. NFPA 70 NEC Zone Classification System The Zone Classification System is offered as an alternative to the Class and Division system. . In the United States, the most commonly followed system is the NEC (National Electric Code), while the rest of the world generally follows the IEC (International Electrotechnical Commission). 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. 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. October 2020 Informational Note No. hazardous areas as the following: An area where a potential hazard (e.g., a fire, an explosion, etc.) Examples are: production facilities in the food industry, chemical plants, oil & gas, and the pharmaceutical industry etc. This paper will discuss and review the current approaches and solutions of dealing with these HSE concerns, especially with the involvement of hazardous and potentially flammable and explosive chemicals. The Zone system has three levels of hazard for gas or dust. gas, vapours, mists and dusts). The last requirement for the explosion is the presence of an ignition source, like a spark or hot surface. 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. November 2021 Some other standards have more quantitative methods which require more knowledge of the plant, an example is the IEC standard 60079-10-1. Sources of such hazards include gases, vapors, dust, fibers, and flyings, which are combustible or flammable. So it is quite obvious that explosions should be prevented as much as possible and still work has to be done to achieve this. Both external and internal temperatures are taken into consideration. THE CURRENT STANDARD . 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. Comparisons between the two systems are not easily accomplished. 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. These areas are classified solely for the purpose of ensuring the safe and proper specification and installation of electrical/electronic equipment. 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. SEWAGE TREATMENT 10/1/20 This concentration is substance specific and lies normally somewhere between the LEL and UEL. Zone 1 if gas group & temp. 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. Zone type (0/1/2/ 20/21/ 22) Zone extent. 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. 0,1 or 2: II B: I: 1 or 2: C: Acetone Benzene Butane Hexane . Zone 2 hazardous areas are typically storage areas but can also be process areas. less than 0.45 mm or MIC ratio is less than 0.40. Zone 1 - A place in which an explosive atmosphere is likely to occur in normal operation occasionally Hazardous Area Classification (HAC) is as follows: Definitions of hazardous area are different as per IEC and NEC. For example, within the U.K. in the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) and in the U.S. in the Occupational Safety and Health Act of 1970 (OSHA). Atmospheres containing propane, acetone, benzene, butane, methane, petrol, hexane, paint solvents or gases and vapors of equivalent hazard.