Probably many of you heard of military grade devices that are meant to withstand wide temperature range, high accelerations, mud and dirt. They must be reliable and work when most needed. But what situation is with other extreme conditions – potentially explosive areas? You will be surprised how many of those areas are around us. Take oil platforms, gas trucks, coal mines, oil tankers, aviation fuel fillers and many other machine facilities that may generate explosive gases or dust. Workers cannot use regular phones or other devices in such areas, because there is always a risk of small sparks that could cause an explosion. Not to use at all is not an option – you may need to do measurements, calculate data and to other tasks where device is simply needed. This is where intrinsically safe equipment is used. There is even a special European Directive called ATEX (Atmospheres Explosibles) that regulates the use of equipment in hazardous areas. For instance lets take a multimeter Fluke 28 II EX. It can be used in explosive environments.
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It is extremely protected multimeter which is certified for use in explosive environment. Multimeter is reliable sealed in IP67 rated case from water, dust and can survive drops from 3 meter high. Its ruggedness allows safe operation in any chemical, gas and dust environments. Anyway, using intrinsically safe multimeter still doesn’t guarantee that there will be no sparks. Measuring procedure is also very important. Just try to measure battery voltage with any multimeter and you will see sparks when touching leads to contacts. But this is different area of expertise where people have to be trained. Same situation is with mobile phones. We always carry cell phones with us. And for a moment did wee think that it would be better to turn it off when fueling car? They are not protected from falling, they are not shielded. It can cause sparks if dropped accidentally. And definitely have seen how small sparks can ignite gas lighter. There is more information about intrinsically safe devices in intrinsic safe mobile phone blog.