In many industries, there are certain areas that are classified as hazardous or Ex areas. This is an area that contains, or may contain, combustible substances such as gas, vapour or dust. Typical hazardous areas include coal mines, grain silos, chemical and petroleum plants, offshore and onshore oil and gas rigs, oil refineries, pharmaceutical plants and paint shops.
During the coal mining process, byproducts in the form of coal dust and methane are produced. The build-up of either of these can be extremely dangerous. Even a tiny spark can set off a disastrous explosion. Similarly, grain silo dust ignited by a spark, has led to tragic explosions.
Safety measures in hazardous areas
In order for ignition to occur, two things are needed: the combustible atmosphere as described above, and a trigger i.e. a spark or flame. Remove one or both of these conditions and an explosion cannot occur.
Removing combustible dust and vapour
Ventilation equipment can dilute or remove dangerous substances from an enclosed area and as a result reduce the risk of explosion. This method is extensively used in the mining and chemical industry.
No trigger
Apart from ‘No Open Flame’ signs, precaution must be taken to prevent electrical equipment from being a source of ignition. A simple electrical switch, for example, can generate an electrical spark every time it is thrown – depending on the type of load. This spark may be enough to act as a trigger for an explosion in a hazardous area. In a similar fashion, sparks can be created by portable electronic devices. In order for devices to be safe for use in hazardous areas, safety precautions have to be built into the design.
Intrinsically safe (IS) instruments
There are several aspects in the design of IS electronic devices, of which reducing or eliminating switch sparking is but one. Other considerations include, fast fuses, controlling component temperatures, eliminating tight component spacing that could lead to a short circuit, and reducing circuit current and energy storage.
R&C Instrumentation is geared to supply a considerable range of intrinsically safe instruments, for instance the Raytek MT4-IS handheld non-contact thermometer for the temperature range -18 to 400°C, the Raytek Mi3-IS 4-wire system fixed pyrometer and the Raytek TX-IS 2-wire loop powered system fixed pyrometer.
As part of the recently launched range of vibration sensors, there is also a wide range of ATEX IEC and Ex certified versions available. Additionally, due to a special request from a mining client, there is now also the UT390B+IS laser distance meter available from stock.
A lesson in the history and evolution of industrial safety systems Schneider Electric South Africa
IS & Ex
One only has to briefly page through the annals of our industrial history to come across truly hair-raising stories of safety systems failing or underperforming with catastrophic repercussions. Fortunately, industrial safety in the last few decades has undergone some truly profound development.
Read more...Windows tablets for hazardous areas Extech Safety Systems
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i.safe Mobile has expanded its intrinsically safe product range with the launch of the IS945.x series rugged Windows tablets, designed for use in hazardous and demanding industrial environments.
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Extech is expanding its portfolio with the Windows-based tablets IS945.1, IS945.2, and IS945.M1. For the first time, EX certification is combined with full Windows compatibility, without compromising on software or security.
Read more...Certified safe power for hazardous industrial environments Conical Technologies
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When working in high-risk environments like oil and gas, petrochemical plants or other hazardous industrial zones, safety isn’t just important, it’s essential. That’s why Traco Power developed the TIB-EX series of DIN rail power supplies, purpose-built to deliver reliable power even in the toughest conditions.
Read more...Parker strengthens explosion safety
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Parker Hannifin has announced that its 37 mm Ex d m coils have attained new ATEX and IECEx Type Examination Certificates according to the latest explosion protection standards.
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Whenever electrical equipment is required for use in hazardous environments they must be designed with intrinsic safety in mind. Darren Barratt, product sales manager at alarm and event management specialist, Omniflex outlines the importance and key aspects of intrinsic safety design.
Read more...Control and monitoring with only one device Pepperl+Fuchs
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Pepperl+Fuchs has expanded its portfolio of K-System isolated barriers for DIN rail mounting (power rail) with the KCD2-SCS interface module. As the first 2-channel AI/AO intrinsic safety barrier with dual function, the module can be configured individually for analogue input or output control signals.
Read more...Hazardous area solutions Extech Safety Systems
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Extech specialises in hazardous area solutions, with offerings ranging from intrinsically safe Zenier Barriers and galvanic isolators to networking infrastructure, mobile devices and RTLS.
Read more...Field service regime key for effective PDS/CPS operation
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While their primary objective is to ensure the safety of people, proximity detection system and collision prevention system installations also have a direct bearing on other critical parameters such as equipment availability and productivity.
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