Conference Paper

Conversion from Division to Zone electrical classification-why and how the worlds largest oil company made the change

Saudi Aramco, Dhahran
DOI: 10.1109/PCICON.2000.882757 Conference: Petroleum and Chemical Industry Conference, 2000. Record of Conference Papers. Industry Applications Society 47th Annual
Source: IEEE Xplore


The introduction in the late 1990s of the Zone electrical area
classification concept into North American standards provided the
catalyst for a major international oil company based in Saudi Arabia to
convert from the “Division” to the “Zone” method
of area classification. The company initially relied on North American
standards to purchase materials but, over the years, sourcing of
materials, and design and construction services gradually shifted away
from North America. This required the company to restructure their
standards and accept materials and installation practices from all over
the world. Today, the company standards accept materials and
installation techniques from a variety of international sources. The
Zone classification system was considered to provide the maximum
flexibility and safety in hazardous locations. Therefore, it was
considered preferable over the Division system from a cost, safety,
maintenance and reliability viewpoint. In late 1999, the company decided
to convert from a Division to Zone Classification system. This paper
discusses details of why and how the company made the change and the
impact of the migration on electrical and instrumentation installations
within the company

Full-text preview

Available from:
  • [Show abstract] [Hide abstract]
    ABSTRACT: 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
    No preview · Conference Paper · Feb 2001
  • [Show abstract] [Hide abstract]
    ABSTRACT: The first project in the United States that has been designed and constructed utilizing the Zone method of classification and the methods of explosion protection allowed for Zones is a new oil field on the North Slope of Alaska. The Zone method of classification and the Increased Safety (Type e) method of protection for Zone-1 areas are used at this facility. The lack of necessary components, difficulties with wiring methods allowed by NEC Article 505, and the incompatibility of existing wiring methods with the new products have all been experienced. Despite these difficulties, the author is convinced that the Zones are here to stay and will be found to provide a safe and cost-effective installation. However, proof of safer and cheaper installations will have to be determined in the future, after some experience and results have been established with which to make comparisons. Some problems encountered are presented here with solution methods and an indication of some of the holes remaining in the process of design and installation for Zone-rated projects. Recommendations are also made for products and changes to codes and standards required for Zones to be truly viable as a method of design and construction.
    No preview · Article · Feb 2003 · IEEE Industry Applications Magazine
  • [Show abstract] [Hide abstract]
    ABSTRACT: The trend for the petrochemical industry in the US is to still classify hazardous locations according to the Division system while Canadian users are moving rapidly to the Zone method of classification. What can be done to generate more interest in Zones in the US? One catalyst for incorporating the Zone method of classification into the North American electrical codes was to avoid the use of explosion proof seals. Despite the lack of confidence in the proper installation of seals, there is little that can be added to a quality control program to improve this situation. Efforts must, therefore, be intensified to develop a less expensive, more reliable method to install and pour scaling compound. Proper classification of unattended sites is still a challenge without more use of gas detectors and adequate ventilation.
    No preview · Conference Paper · Oct 2003