Selecting the correct explosion-proof electrical panel for a hazardous area installation is one of the most critical engineering decisions in any oil & gas, petrochemical, or chemical processing project. A wrong selection can compromise personnel safety, lead to regulatory non-compliance, and result in costly project delays. This guide walks you through the key factors to consider when specifying Ex proof panels for Zone 1 and Zone 2 classified locations.

Understanding Hazardous Area Zone Classifications

Before selecting any explosion-proof equipment, the hazardous area must be properly classified by a competent person or ATEX/IECEx-qualified engineer. Under the IEC 60079-10 standard, gas and vapor hazardous areas are divided into three zones. Zone 0 is an area where an explosive gas atmosphere is present continuously or for long periods. Zone 1 is an area where an explosive gas atmosphere is likely to occur in normal operation. Zone 2 is an area where an explosive gas atmosphere is not likely to occur in normal operation, but if it does occur, it will only exist for a short period.

The vast majority of oil & gas processing facilities and petrochemical plants in the UAE contain Zone 1 and Zone 2 classified areas, making the correct selection of Ex-rated panels for these zones particularly important.

Protection Concepts for Ex Proof Panels

The IEC 60079 series defines several protection concepts applicable to electrical panels and enclosures. The most commonly used for panels in Zone 1 and Zone 2 locations are as follows.

Flameproof enclosure (Ex d) is one of the most widely used protection methods for Zone 1 applications. The enclosure is designed and built to withstand an internal explosion and prevent the ignition from propagating to the surrounding explosive atmosphere. Ex d panels are robust, reliable, and suitable for harsh environments.

Purging and pressurization (Ex p) involves maintaining a positive internal pressure within the enclosure using clean air or an inert gas such as nitrogen, effectively preventing the ingress of the flammable atmosphere. Ex p panels are ideal when standard, non-Ex rated components such as PLCs, VFDs, and instrumentation need to be housed in a hazardous area, as it allows the use of conventional equipment within a certified pressurized enclosure.

Increased safety (Ex e) is a protection concept where additional measures are applied to prevent sparks, arcs, and excessive temperatures. While Ex e is not suitable for equipment that produces sparks under normal operation, it is widely used for terminal boxes, junction boxes, and lighting in Zone 1 and Zone 2 areas.

Key Selection Criteria

When selecting an explosion-proof panel for your facility, the following parameters must be clearly defined in your specification. The gas group must be identified, as different flammable gases and vapors have different explosion characteristics. The IEC gas groups range from IIA (propane) to IIB (ethylene) to IIC (hydrogen and acetylene), with IIC representing the most severe ignition risk. Your panel must be certified for the appropriate gas group present at your facility.

The temperature class is equally important. Flammable gases ignite at different temperatures, so the surface temperature of the Ex equipment must remain below the ignition temperature of the gas present. Temperature classes range from T1 (450°C) to T6 (85°C), with T4 and T5 being the most commonly specified in UAE oil & gas projects.

The ingress protection (IP) rating of the enclosure must also be specified based on the environmental conditions of the installation site. For outdoor installations in the UAE, a minimum of IP65 is typically required, while IP66 or IP67 is preferred for areas exposed to water jets or immersion.

The material of construction must be selected based on the corrosiveness of the surrounding environment. GRP (Glass Reinforced Polyester) is preferred for highly corrosive offshore or coastal environments, while 316 stainless steel is used where chemical resistance and hygiene are priorities. Cast aluminum enclosures offer a lightweight and cost-effective solution for less aggressive environments.

Why Choose Team Switchgear and Control LLC

At Team Switchgear and Control LLC, we have extensive experience in engineering and manufacturing explosion-proof panels for Zone 1 and Zone 2 classified areas across the UAE and GCC region. Our engineering team works with clients from the earliest stages of project design to ensure the correct protection concept, gas group, temperature class, and enclosure material are selected for each specific application. All our panels are factory acceptance tested (FAT) before delivery and are supplied with full IECEx/ATEX certification documentation. Reach out to our team for a no-obligation technical consultation.