Products intended for use in Hazardous Areas must respect severe standards and must be equipped with adequate safety systems. Rules regarding plants safety are set out by international codes; the most important globally are:
- ATEX ("Atmosphères Explosibles") Directives in the European Union;
- NEC (National Electrical Code) in the United States;
- IECEx, International Electrotechnical Commission System for Certification in Standards Relating to Equipment for use in Explosive Atmosphere. It is a voluntary certification scheme, attracting the adhesions of more and more Countries around the world.
Let's take a quick look at the three:
1. ATEX
There are 2 ATEX Directives:
- ATEX 1999/92/EC, dealing with people’s health and safety in Hazardous Areas;
- ATEX 2014/34/EU (which in 2016 replaced Directive 94/9/EC) explaining safety requirements for the products, dividing them into groups and categories, defining rules for their certification (mainly entrusted to ATEX Notified Bodies).
ATEX guidelines follow the IEC Zone System scheme in the classification of explosive areas: Zone 0, 1, 2 or 20, 21, 22 depending on the type of explosive substance (gas or dust) and the probability of explosive mixture formation.
2. NEC
The National Electrical Code sets standards for the safe installation of electrical wiring and equipment in the United States. Articles 500 to 517 deal with Dangerous Areas, classifying them in subdivisions (by type, condition and nature of explosive danger) and zones, similarly to the European system. Each approach provides different standards for products certification and plants safety.
3. IECEx
IECEx’s basic goal is to make easier the trade of products intended for use in Hazardous Areas: the IECEx certificate is electronic and allows manufacturers to reduce test, certification and marketing costs. On the other hand, buyers can count on international standards about plants safety and can easily compare products from different suppliers.
There are 3 main IECEx certification documents:
- CoC - Certificate of Conformity;
- ExTR - Test Report of type tests performed on the product;
- QAR - Quality Assessment Report.