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Most Refineries, Drilling Platforms, and chemical plants are equipped with receptacles used for powering equipment. This can present a shock hazard; therefore, the National Fire Protection Association (NFPA) and Occupational Safety and Health Administration (OSHA) require ground-fault circuit interrupters (GFCIs) on all receptacle powering equipment used by personnel. However, these GFCIs are not part of the building?s permanent wiring. Due to the lack of GFCIs at voltages above 240 V, both the NFPA and OSHA require employers to implement the assured equipment-grounding conductor program for all temporary wiring installations.

A common assumption is that protective devices, such as circuit breakers, in hazardous areas, such as Class I, Division 1 and 2 or Zone 1 and 2, will work at their designed voltage, current, and short- circuit ratings in the same manner as in non-hazardous areas. However, this is not always true. The electrical components of these protective devices can be affected by the type of enclosure used for their installation within a hazardous area. This paper will explore the characteristics and behavior of the short-circuit ratings for electrical equipment installed in a hazardous area. Some factors, such as the type of flammable and combustible material present, play a role in limiting these short-circuit ratings. In addition, material groups create the atmosphere for installed devices and are a deciding factor on short-circuit ratings.

Sparks and hot surfaces are the most common sources of ignition encountered in hazardous locations. However, there is a struggle with how to deal with electronic devices such as medical devices, cell phones, tablet computers, hand-held devices, etc. in a classified area or “Explosive Atmosphere”. It is quite simple to limit the use of cell phones in an explosive atmosphere, but there is much more to consider for the use of other electronic devices. This issue has become a common concern amongst petrochemical companies. While sparks and hot surfaces bring the main risks associated with the operation of equipment in explosive atmosphere, there are also risks derived from static electricity, lightning, stray currents, radio-frequency radiations, electromagnetic waves produced by radio-frequency (RF) transmitters, and optical radiations such as laser radiation. To aid with a potential solution for this problem, this paper will explore the sources, effects, equipment, protection, and standards in Class I, Division 1 (Zone 1) or Division 2 (Zone 2) locations.

This paper evaluates the relationship between hazardous-rated electrical equipment, which is suitable for installation in Class I, Division 1 (Zone 1), or Division 2 (Zone 2) locations, and an arc-rated switchgear, which is designed to withstand the effects of an internal arcing fault. Using UL 1203 (Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous (Classified) Locations), IEEE C37.20.7 (IEEE Guide for Testing Metal-Enclosed Switchgear Rated Up to 38 kV for Internal Arcing Faults), and the paper titled “Pressure Developed by Arcs,” this paper will explore the applicability of hazardous-rated equipment in the protection of personnel from an arc-flash hazard.

Electrical equipment installed within electrically classified areas—Class I, Division 1 (Zone 1), or Division 2 (Zone 2) locations—require techniques to mitigate flame propagation. Class I, Divisions 1 and 2, or explosion-proof (NEMA 7) techniques are the most commonly used for this purpose. Other techniques, such as enclosed break, flame proof, and restricted breathing, are commonly available methods. A previous PCIC paper (Mendler et al. , 2015) explored the electrical arc flash mitigation of the NEMA 7 design. It was found that this design mitigated the electrical arc flash energies, and helped protect personnel from electrical hazard. This paper will explore the percentage reduction in electrical arc flash energies outside the enclosure when an arc occurs inside an enclosure. This will be accomplished using a simpler lighter explosion-protected design. The results will be obtained using an analytical approach, a computational fluid dynamics (CFD) analysis, and with further testing using prototypes that will show enhanced personnel protection.

Most refineries, drilling platforms, and chemical plants are equipped with receptacles used for powering equipment. This can present a shock hazard; therefore, NFPA and OSHA require ground-fault circuit interrupter (GFCI) on all receptacles powering equipment used by personnel and are not part of the building permanent wiring. Due to the lack of GFCI at voltages above 240 V, both NFPA and OSHA require employers to implement the assured equipment grounding conductor program for all temporary wiring installations.

This paper evaluates the relationship between hazardous-rated electrical equipment, which is suitable for installation in Class I, Division 1 (Zone 1), or Division 2 (Zone 2) locations, and an arc-rated switchgear, which is designed to withstand the effects of an internal arcing fault. Using UL 1203 (Explosion-Proof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous (Classified) Locations), IEEE C37.20.7 (IEEE Guide for Testing Metal-Enclosed Switchgear Rated Up to 38 kV for Internal Arcing Faults), and the paper titled “Pressure Developed by Arcs,” this paper will explore the applicability of hazardous-rated equipment in the protection of personnel from an arc-flash hazard.

This paper will explore the maintenance of electrical equipment. Specifically it will look at: 1) Why maintenance is performed on electrical equipment? 2) What, legal or other, drivers are behind performing electrical equipment maintenance? 3) Electrical equipment maintenance is performed on an interval, but what is the purpose of this interval and how is it determined? 4) What is the difference between breakdown, preventive, and predictive electrical equipment maintenance methods and when should each be applied? 5) What do available testing technologies, such as - insulation resistance, power factor, oil analysis, partial discharge, infrared, ultrasonic, functional analysis, etc., tell us about the condition of electrical equipment and when should they be applied to various types of electrical equipment? 6) What does analysis of electrical equipment maintenance data/information reveal about the frequencies, philosophies, and foundation on which maintenance is performed?