Hazardous areas are those defined as areas of potential explosion risk due to the presence of flammable gas or vapor. 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! The Zone Classification System is offered as an alternative to the Class and Division system. Home About Us News Hazardous Environment Classifications: NEC vs IEC, Posted March 11, 2019 by springercontrols. Atmosphere containing a flammable gas, a flammable liquid produced vapor or a combustible liquid-produced vapor whose MESG is greater than 0.75 mm or MIC ratio is greater than 0.40 and less than 0.80 - such as carbon monoxide, ether, hydrogen sulfide, morphline, cyclopropane, ethyl, isoprene, acetaldhyde and ethylene or gases of equivalent hazard. WATER TIGHTNESS These are typically process areas where gases are more likely to be present. NFPA 70 NEC uses the familiar Class/Division system and has added an Americanized version of the International Electrochemical Commissions (IEC) IEC Zone system which maintains the NEC wiring methods and protection techniques. Marking "EEx d" in Accordance with EN 50 0 14 and 50 018 . 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. of A hazardous area can be defined as any location where there is risk of an explosion. Class 1/Div 2 ATEX Zone 2 Computers. Safety is ensured in the event of frequently occurring disturbances or equipment faults which normally have to be taken into account. THE PRODUCTS YOU NEED, National Electric Code 2020 edition National Fire Protection Association. Hazardous area equipment is categorized into category-1 for Zone 0 or Zone 20, category-2 for Zone 1 or Zone 21, and category-3 for Zone 2 or Zone 22. TLS OFFSHORE CONTAINER Class I, Zone 0 or Zone 1 locations may not abut Class I, Division 1 or Division 2 locations. Zone 0, 1, and 2 locations are those in which flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. the inside of tank truck or the interior of a dust filter). An area where combustible dusts or ignitable fibers and flyings are likely to occur under normal operating conditions. 0,1 or 2: II B: I: 1 or 2: C: Acetone Benzene Butane Hexane . No other aspect of safety receives more attention in the form of codes and standards. 5mm -750C Electrical Resistivity. This process is called hazardous area classification. Offshore Living Quarter Also known as non-hazardous or ordinary locations, these locations are determined to be neither Class I, Division 1 or Division 2; Zone 0, Zone 1 or Zone 2; or any combination thereof. 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". Ignitable concentrations of flammable gases or vapors which are likely to occur under normal operating conditions. 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. A high level of protection is ensured. Zones 1 or 2. The zone classification for gases is divided into three zones, namely Zone 0, Zone 1 and Zone 2 and for dusts Zone 20, Zone 21 and Zone 22. AddThis use cookies for handling links to social media. 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. Zones also have the added benefit of including the area classification with the zone description. In the United Kingdom, Sira and Baseefa are the most well known such bodies. Beside sufficient fuel, also sufficient oxygen is needed for combustion of the mixture. 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. January 2023 Under the "Zone" system, hazards are defined for gas as Zone 0, 1 or 2, with 0 as the highest hazard, and for dust as Zone 20, 21 or 22, with 20 as the . This value of this LOC differs per substance and depends also on the inert gas for achieving a low oxygen concentration. Determined to be none of the above. This is exactly defined as the limiting concentration of oxygen below which combustion is not possible, independent of the concentration of fuel. The codes and standards used in this process provide guidance for selecting,. The Zone system has three levels of hazard for gas or dust where the Division system has two. July 2021 October 2019 So a zone 0 is the most hazardous zone and a zone 2 is a less hazardous zone. Informational Note: For further information regarding classification and ventilation of areas involving closed-circuit ammonia refrigeration systems, see ANSI/IIAR 2-2014. Well recognized and clear IEC Standard IEC 60079-10-2:2015 Hazardous Area Classification for explosive dusts Significant influence on spending's for safety . NFPA 70 NEC Zone Classification System The Zone Classification System is offered as an alternative to the Class and Division system. 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. Standards and regulations exist to identify such locations, classify the hazards, and design equipment for safe use in such locations. SPARTANs Zone 1 part code begins SPX, Zone 2 SPZ and industrial products having a SPI prefix. No long-term contract. There are three zones for gas: Zone 0, Zone 1 and Zone 2. Classification of locations, testing and listing of equipment, and inspection of installation, is typically overseen by governmental bodies. Informational Note No. The flash-point is the temperature at which the material will generate sufficient quantity of vapor to form an ignitable mixture. The value is represented is volume percentage of oxygen. It may exist because of repair, maintenance operations, or leakage. Zone 1 is an area in which an explosive atmosphere is likely to occur occasionally in normal operation. Please read AddThis Privacy for more information. September 2018 For example, in the US by the Occupational Safety and Health Administration. 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). 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. Gas a. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. Class I Zone 2 Hazardous Areas. 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. If you want to promote your products or services in the Engineering ToolBox - please use Google Adwords. For example the EI 15 and API 500/505 describe specific installations and several conditions for the oil and gas industry. . Raytec do not currently offer any lighting solutions for Zone 0. In electrical and safety engineering hazardous locations HazLoc pronounced hazlk are places where fire or explosion hazards may exist. Area's are divided into zones. Zone 1 an area in which an explosive gas-air mixture is likely to occur in normal operating conditions. *unless risk assessment states a higher or lower category is required. Choose the right method for Hazardous Area Classification! November 2021 Group is divided in three groups where Group I is reserved for mining locations. | For Dust this would be Zone 22. Terminology for both hazards and protective measures can vary. ESS Container 1: As a guide to classification of Zone 22 locations, refer to ANSI/ISA 60079-10-2 (12.10.05)-2013, Explosive Atmospheres Part 10-2: Classification of areas Combustible dust atmospheres. Locations shall be classified depending on the properties of the flammable vapors, liquids, or gases that may be present and the likelihood that a flammable or combustible concentration or quantity is present. Locations are thus classified by type and risk of release of gas, vapor, or dust. 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. SEWAGE TREATMENT 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. . Many items of EEx rated equipment will employ more than one method of protection in different components of the apparatus. THE CURRENT STANDARD . Group defines the type of the hazardous material in the surrounding atmosphere. 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. Therefor Hazardous Area Classification (HAC) is the first important step in achieving an explosion safe installation or work environment. Fundamentally, for an explosion to take place, flammable or explosive gases, vapours, mists or dusts will be present. Comparison of Zones and Divisions. Q: Are Divisions and Zones equivalent to one another? Figures show that appr. The Zone system of hazardous area classification, defines the probability of the hazardous material, gas, or dust, being present in sufficient quantities that can generate explosive or ignitable mixtures. January 2021 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. * Zone 2 a . 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. Zone 0 is an area in which an explosive atmosphere is present continuously for long periods of time or will frequently occur. How to perform Hazardous Area Classification? August 2020 The choice of which standard to use for the hazardous area classification is something which is very important. 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. Zone 1 . Zone 2 hazardous areas are typically storage areas but can also be process areas. Zone 1 (unless separated by a fire wall)P.G.Sreejith, Kerala. 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. Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 . Explosion-proofing designs equipment to contain ignition hazards, prevent entry of hazardous substances, and, contain any fire or explosion that could occur. 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. 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. A60 . RP 505 is referred to as the zone system. Informational Note No. 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. Zone 0/20: An area in which an explosive atmosphere is present continuously or for long periods or frequently. March 2022 Zone 1 - A place in which an explosive atmosphere is likely to occur in normal operation occasionally 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. less than 0.45 mm or MIC ratio is less than 0.40. Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 September 2019. 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). [10][11] Some of these are specifically for hazardous locations: All equipment certified for use in hazardous areas must be labelled to show the type and level of protection applied. 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). Ambient Temperature (-20C to +40C if not marked) Establish Zone Based on "IEC 60079-10". 2: For the requirements for electrical and electronic. 2: Where gas detection, Informational Note No. In other cases, the atmosphere is normally non-hazardous, but a dangerous concentration can be reasonably foreseensuch as operator error or equipment failure. The design of the equipment must ensure protection, even in the event of rare incidents relating to the equipment. The temperature classification on the electrical equipment label will be one of the following (in degree Celsius): The above table shows that the surface temperature of a piece of electrical equipment with a temperature classification of T3 will not rise above 200C. WELDING INSPECTION A major safety concern in all workplaces is the occurrence of fires and explosions. API 500/505 mostly for onshore and offshore oil and gas applications. Division II Comprising of Area Same as Zone 2. 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 potential few examples of this are: The air space inside a tank of petrol 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. Protecting against fire and explosion is of interest for both personnel safety as well as reliability reasons. 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. Examples are: production facilities in the food industry, chemical plants, oil & gas, and the pharmaceutical industry etc. 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. So the flammable range of a substance is the concentration of gases and vapors in air between the Lower Explosion Limit and the Upper Explosion Limit. August 2021 Carbon monoxide, ether, hydrogen sulfide, . Only emails and answers are saved in our archive. Readers with specific questions should refer to the applicable standards or consult with an attorney. October 2018 Zone 2. Zone 0 (hazardous area) An area in which an explosive gas-air mixture is continuously present or present for long periods. Zone 1 fittings are supplied as silver, Zone 2 as dark grey and industrial fittings as white. Although every application is different, for the ease of monitoring and specification each hazardous area is classified as a particular level or zone. The a subdivisions have the most stringent safety requirements, taking into account more than one independent component faults simultaneously. This concentration is substance specific and lies normally somewhere between the LEL and UEL. 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 22 Zone 21 Zone20 A hazardous atmosphere formed by dust cloud in air is not likely to occur in . Area Classification - Hazardous Locations are classified by the likelihood of an ignitable concentration of combustible material being present. The process of determining the type and size of hazardous locations is called classification. . . Ignitable concentrations of flammable gases or vapors which are present continuously or for long periods of time. NFPA 70 NEC Classes, Divisions and Groups. Use this hazardous area guide to NFPA 70 location classes, divisions & groups to understand potentially dangerous situations at a glance. Dry Container Temperature classification, except for intrinsically safe apparatus. An oversimplification of this example is shown in Table 1. Note to paragraph (g)(4) of this section: Low ambient conditions require special consideration. Sources of Each chemical gas or vapour used in industry is classified into a gas group. 1994-2020, W.W. Grainger, Inc. All Rights Reserved. 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. 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. That is why the use of mobile phones on petrol forecourts are banned. The NEMA enclosure rating or IP code may also be indicated, but it is usually independent of the Classified Area suitability. 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. November 2022 This was accompanied by electrically-initiated explosions of flammable gas such as fire damp (methane) and suspended coal dust. Unlike ATEX which uses numbers to define the safety "Category" of equipment, namely (1,2 3), the IEC continued to utilise the method used for defining the safe levels of intrinsic safety namely "a" for zone 0, "b" for zone 1 and "c" for zone 2 and apply this Equipment Level of Protection to all equipment for use in hazardous areas since 2009. 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). Equipment can be designed or modified for safe operation in hazardous locations. Google use cookies for serving our ads and handling visitor statistics. 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.