The upper explosion limit of a substance is the highest concentration (in volume percentages for gases and liquids) of a gas or a vapor in air capable of producing a flash of fire in the presence of an ignition source. 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. Conversely if the same material is heated and handled above its flash-point, the area must be classified for proper electrical system design, as it will then form an ignitable mixture.[5]. Ex s is a coding referenced in IEC 60079-0. These hazardous (classified) locations are assigned the following designations: For definitions of these locations, see 1910.399. 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. Zone Hazardous Location 2 Table of . The key difference between Divisions and Zones relate to terminations. As a guide for Zone 0, this can be defined as over 1000 hours/year or >10% of the time. Container Test Subscribe 6.9K views 2 years ago Oil and Gas Zone Classifications: A) Hazardous Area Classification It's cable reimagined No DVR space limits. 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. September 2022 The NEMA enclosure rating or IP code may also be indicated, but it is usually independent of the Classified Area suitability. May 2019 Refrigerated Temperature Control Zone 1 - Explosive atmospheres are likely to occur. 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. 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. Magnesium, Titanium), IIB Nonconductive dusts (eg. February 2021 1910.307 (g) (2) the National Fire Protection Association (NFPA) 70, National Electric Code(NEC). This means that the electrical equipment is safe for use within these area by applying special protection strategies. The a subdivisions have the most stringent safety requirements, taking into account more than one independent component faults simultaneously. December 2013, All Choose the right method for Hazardous Area Classification! Hazardous Environment Classifications: NEC vs IEC, IEC (International Electrotechnical Commission), Group E Metal dusts (eg. 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. coal and charcoal), Group G Nonconductive dusts (eg. Division defines the likelihood of the hazardous material being present in an explosive or ignitable concentration.Class I flammable gases and vapors are grouped into one of four groups(Groups A, B, C or D)based on their physical properties and the ease in which they can be ignited. 1: Normal operation is considered the situation when plant, Informational Note No. September 2018 *unless risk assessment states a higher or lower category is required. Atmospheres containing propane, acetone, benzene, butane, methane, petrol, hexane, paint solvents or gases and vapors of equivalent hazard. Safe for the hazardous (classified) location. So for an explosion there must be enough fuel. That is why the use of mobile phones on petrol forecourts are banned. 7: For further information on application of electrical, Informational Note No. For liquids, gases and vapours: Zone 0, Zone 1 and Zone 2. You will find this equipment in paint factories, a warehouse or around a bag dump station. 1994-2020, W.W. Grainger, Inc. All Rights Reserved. Both external and internal temperatures are taken into consideration. SEWAGE TREATMENT 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. 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. 14 4. In some cases, it must be certified as meeting that standard. Area Classification. Accommodation Cabin Hazards in this group gas can be ignited very easily indeed. These are typically process areas where gases are more likely to be present. The substance referred to by classhas a low probability of producing an explosive or ignitable mixture and is present only during abnormal conditions for a short period of time - such as a container failure or system breakdown. The label will always list the class, division and may list the group and temperature code. Have a think about it next time youre filling up! April 2021 Atmosphere containing carbonaceous dusts, Atmosphere containing combustible dust not included in Group E & F - such as. 2: This classification includes, Informational Note No. How to perform Hazardous Area Classification? 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. If equipment is marked, for example, Ex e II T4 then it is suitable for all subgroups IIA, IIB and IIC. A: No. . WHEN YOU NEED THEM. Electronic equipment, including lighting, needs to be purpose designed for use in hazardous areas to prevent a spark occurring and igniting any flammable substances. Hazardous area classification. No other aspect of safety receives more attention in the form of codes and standards. taper per foot. 41 gas explosions per year occur within the UK and app. Click on the zone to learn more about the classification according to IEC 60079-10 standards. Flameproof "d" - This protection technique is permitted for equipment in the Class I, Zone 1 locations for which it is approved. So the following conditions must be met for an explosion to occur: Represented by the following explosion triangle. NEGATIVE PRESSURE 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. >> For Gas/Vapor this would be Zone 2. So yes, it is important to choose the right model and always wonder what am I assessing?. 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. This page was last edited on 20 January 2023, at 22:32. Arcing electrical equipment in unclassified . 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. Flammable atmosphere expected to be present inside the storage tank continuously, hence it has been classified as zone 0. [4], Flammability of combustible liquids are defined by their flash-point. Sources . May 2022 NEW METHODS FOR HAZARDOUS AREA CLASSIFICATION FOR EXPLOSIVE GAS . 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. Atmospheres containing combustible flyings. Horizontal. What is an Explosion Protection Document? The following content is only related to flammable substances and not to pyrotechnic substances or other instable substances, among those who can decompose. What Are All Those Gadgets On A Multitool? 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. The last requirement for the explosion is the presence of an ignition source, like a spark or hot surface. This is an important factor in the classification of hazardous areas. Reefer Container Where pyrophoric materials are the only materials used or handled, these locations need not be classified. 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. Iso Container In other cases, the atmosphere is normally non-hazardous, but a dangerous concentration can be reasonably foreseensuch as operator error or equipment failure. | For Gas/Vapor this would be Zone 0. Flammable liquids with a high flash point are less hazardous than liquids Youre phone isnt rated for use in hazardous areas. Laboratory Container January 2021 Container Accessories In general, all types of equipment installed within the hazardous area shall be . For example, in the US by the Occupational Safety and Health Administration. ADNOC Typical gas hazards are from hydrocarbon compounds, but hydrogen and ammonia are also common industrial gases that are flammable. 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. | For Dust this would be Zone 21. Enclosures can be pressurized with clean air or inert gas, displacing any hazardous substance. Explosions can cause significant damage along with severe injury or worse loss of life. 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. Some equipment in Division 2 areas do not require a specific label, such as standard 3 phase induction motors that do not contain normally arcing components. It is always balancing between not defining such areas too large (with highly costs for prevention of ignition sources) or too small (unsafe situations). 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. 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. Zone 1 - A place in which an explosive atmosphere is likely to occur in normal operation occasionally See Figure S-1 for an explanation of this marking. Equipment that the employer demonstrates will provide protection from the hazards arising from the flammability of the gas or vapor and the zone of location involved and will be recognized as providing such protection by employees need not be marked. In North America the suitability of equipment for the specific hazardous area must be tested by a Nationally Recognized Testing Laboratory, such as UL, FM Global, CSA Group, or Intertek (ETL). It is created based on input from the Process Flow Diagrams, Piping & Instrumentation Diagrams and the Equipment Location Plan . 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. (1) Zone 0. 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 July 2019 . 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. In the IEC standards hazardous areas are classified into zones based upon the frequency and duration of an explosive atmosphere. In the United States, the hazardous location classification system is defined by the National Fire Protection Association (NFPA) 70, National Electric Code(NEC). For example, a Class 1, Div 1 area where Group A may be present would be defined as an area where flammable gases or vapors may be present under normal operating conditions. The hazardous area classification system determines required protection techniques and methods for electrical installations in the location. Zone 22 Zone 21 Zone20 A hazardous atmosphere formed by dust cloud in air is not likely to occur in . For dusts: Zone 20, Zone 21 and Zone 22. 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). This article is not a substitute for review of current applicable government regulations, industry standards, or other standards specific to your business and/or activities and should not be construed as legal advice or opinion. The Zone system has three levels of hazard for gas or dust where the Division system has two. Vertical. THE PRODUCTS YOU NEED, 10: For information on electrical resistance trace heating for hazardous (classified), Informational Note No. Category 1 equipment may be used in zone 0, zone 1 or zone 2 areas. >> For Gas/Vapor this would be Zone 0. June 2022 Hazardous Area Classifications D103222X012 Product Bulletin 9.2:001 September 2019. Equipment is placed into protection level categories according to manufacture method and suitability for different situations. Photo 2. Atmospheres containing acetylene, hydrogen, carbon disulphide or gases and vapors of equivalent hazard. Comparison of Zone 2 and Division 2 TABLE 1 - AREA CLASSIFICATIONS Division 1: Where ignitable concentrations can exist all of the time or some . 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. . Carbon monoxide, ether, hydrogen sulfide, . We will go deeper into ignition assessments in another blog. Copryright 2023 Springer Controls Company . The autoignition temperature is the lowest temperature at which the substance will ignite without an additional heat or ignition source (at atmospheric pressure). In Northerm America, instead of the zone classification system, the Class/Division system is used. Beside sufficient fuel, also sufficient oxygen is needed for combustion of the mixture. eg Production Area, area surrounding zone 0. A: Yes. Category 3 equipment may only be used in zone 2 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. The CE mark is complemented with the Ex mark: A yellow-filled hexagon with the Greek letters (epsilon chi), followed by the Group, Category, and, if Group II, G or D (gas or dust). . 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. Zone 0, 1, and 2 locations shall include those specified in 505.5 (B) (1), (B) (2), and (B) (3). Comparison of Zones and Divisions. 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. January 2023 - Zone 0: An area where an explosive gas-air mixture is continuously present or present for long time (continuous hazard, whose estimated duration is higher than 1000 hours/year) - Zone 1: An area where an explosive gas-air mixture is likely to occur during normal . 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. Temporary Refuge Explosion protection must be ensured during normal operation. . 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). gas, vapours, mists and dusts). 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. There are several ways of how to perform hazardous area classification, all described in several standards or codes of practise. Substance properties are specific for the amount of fuel needed to get an explosion when all other conditions are met. These applications will - due to browser restrictions - send data between your browser and our server. 1: The term "Class I" was originally included as a prefix to, Informational Note No. Zone 1 if gas group & temp. Zone 1 . December 2021 1. Q: Can I use a piece of equipment approved for use in a Division 1 hazardous location in a Division 2 hazardous location? The term equipment is applied both for fixed equipment and mobile equipment that are operated in such area. .14 . Please read Google Privacy & Terms for more information about how you can control adserving and the information collected. Zone 0/20: An area in which an explosive atmosphere is present continuously or for long periods or frequently. Hazardous classified locations are areas where the possibility of fire or explosion hazards may exist under normal or abnormal conditions because of the presence of flammable, combustible or ignitable gases, vapors, liquids, dust, or fibers/flyings. Areas with possible fire or explosion risks due to explosive atmospheres and/or mixtures - are called hazardous (or classified) locations or areas. IECEx Karandikar Certification A Zone 1 hazardous area is classified as a place in which an explosive atmosphere consisting of a mixture with air or flammable substances in the form of gas, vapour or mist is likely to occur in normal operation occasionally. Zone 2 hazardous areas are typically storage areas but can also be process areas. 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 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. 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. >> For Gas Vapor this would be Zone 1. SPARTANs Zone 1 part code begins SPX, Zone 2 SPZ and industrial products having a SPI prefix. LIFTING TEST Hazardous area classification is a rigorous method of determining where an explosive environment may be present. 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. paul heaton and jacqui abbott islands in the stream, case elegance humidor, pask group east melbourne,