Installation of zone equipment in the US-initial experiences

The Zone method of area classification of hazardous locations is now allowed in the US, and thus the adoption of the methods of protection employed under IEC are now permitted by application of NEC [1] Article 505. Although the Zone products have been available in Europe and elsewhere in the world, their level of availability and methods of application in the US have provided a unique experience adapting the available products to NEC allowed wiring methods. Completion of the first Zone project in the US provides the first opportunity to see if this Zone method should be further developed and supported. A description of problems encountered during design and installation, methods used to solve the problems and the end results are presented here. An evaluation of the end result, compared with traditional Division installation and presentation of the areas of change that are yet required to make the Zone method of classification and protection truly viable, are also provided.