Did you know that many of our load cells, indicators, and junction boxes are also optionally available for hazardous areas? Explosion protection is a decisive factor for industrial weighing systems in hazardous environments today. But what exactly is meant by a hazardous area?
What is a hazardous area?
A hazardous area refers to an area in which a mixture of air and flammable substances – such as gases, vapors, mists, or dust – can occur, which can ignite in an explosive manner if ignited. Such ignitions can be triggered by chemical reactions, spark formation, or electromagnetic radiation.
The risk zones are classified according to the frequency and nature of the potentially explosive atmosphere:
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Zones 0, 1, 2 – for gases and vapors
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Zones 20, 21, 22 – for combustible dust
ATEX, AREX, and explosion protection – What’s behind it?
ATEX (“ATmosphère EXplosible”) is the EU Directive 2014/34/EU for equipment and protective systems in hazardous areas. In Germany, the directive is implemented via the Explosion Protection Products Ordinance (11. ProdSV). Equipment requires CE and Ex labeling as well as a declaration of conformity.
In everyday language in German-speaking countries, people often refer to AREX, which means ATEX/explosion protection. For load cells and complete weighing systems, it is crucial that both mechanical and electrical ignition sources are avoided – whether through sparks, heating, or impact.
Ex-zones and equipment categories
Potentially explosive areas are divided into zones:
Gases/vapors:
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Zone 0: permanently explosive atmosphere
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Zone 1: occasionally explosive atmosphere
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Zone 2: rare explosive atmosphere
Dust:
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Zone 20: permanently hazardous dust atmosphere
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Zone 21: occasionally
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Zone 22: rarely
The ATEX equipment categories are based on the zone:
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Category 1 → Zone 0/20
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Category 2 → Zone 1/21
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Category 3 → Zone 2/22
A weighing system in Zone 1 or 21 therefore requires at least Category 2 Ex-components.
Explosion-proof load cells – safety down to the detail
Load cells for hazardous areas are ATEX-tested and marked with the Ex-symbol. They are designed in such a way that, in the event of a fault, no sparks or inadmissible heating occur – e.g., through limited electrical power or secure encapsulation.
Typical markings:
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Equipment group and zone (gas or dust)
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Equipment category
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Protection type (e.g., intrinsically safe “Ex i” or flameproof enclosure “Ex d”)
For North American markets, there are comparable certifications such as FM that meet similar requirements.
Explosion protection for the entire weighing system
A complete weighing system includes load cells, a junction box or terminal box, and indicators. All components must be matched to the respective hazardous area. Intrinsically safe signal barriers (Ex-i) are often used so that only limited energy is present in the Ex-zone.
Installation, shielding, grounding, cable routing, and instruction manuals are also part of explosion protection. Without correct assembly and maintenance, ATEX conformity does not apply.
Your partner for explosion-proof weighing technology
We offer load cells, indicators, and junction boxes that are suitable for use in hazardous areas. Our products meet the requirements of the ATEX/AREX directives and guarantee reliable and safe measurement values – even under extreme conditions.
Explosion-proof components are a must if you operate scales or weighing systems in hazardous areas. From the load cell to the terminal box and the indicator – we have the right solutions for your requirements.
Contact us today for individual advice or request your quote for your weighing system in hazardous areas directly.