Installing hazardous area equipment requires compliance with Class/Division or ATEX/IECEx standards. Proper mounting, grounding, cable selection, certified cable glands, and approved stopping plugs help maintain safety, equipment integrity, and regulatory compliance.
The installation of rated hazardous area equipment in both Class/Division (or Zone) and ATEX/IECEx hazardous locations is governed by specific standards that define the physical, mechanical, and electrical requirements for each environment. These requirements vary significantly depending on the level of risk. For example, the installation requirements for equipment in a Class I, Division 1 location are considerably more stringent than those for a Division 2 area.
Because of these differences, installation should always be performed by qualified personnel with a solid understanding of the applicable standards and local regulations. Failure to follow the relevant requirements can result in the installation being rejected by the facility or electrical inspector and, more importantly, may compromise safety.
Regardless of the standard being followed, the following hazardous area equipment installation best practices should always be observed:
- Particularly for Pan/Tilt/Zoom (PTZ) cameras, ensure there are no restrictions inhibiting their movement. Verify that no structural elements, piping, cable trays, or other obstructions will interfere with the camera’s range of motion.
- Use an adequate mounting structure. The mounting surface must be capable of supporting the weight of the equipment and resisting environmental loads such as vibration, wind, and process-related movement.
- Follow the manufacturer’s installation instructions. Equipment must be mechanically installed in accordance with the manufacturer’s recommendations and specifications.
- Provide secondary fall protection. While not specifically required by every standard, equipment should always have a secondary means of retention in the event of a mounting failure. This is typically accomplished using a safety lanyard or cable rated for the load.
- Properly ground the equipment. Hazardous-area equipment must have an external grounding terminal. The manufacturer’s installation manual should specify the minimum wire gauge and grounding requirements.
The information below primarily applies to equipment that uses flameproof or explosion-proof protection methods.
Explosion-proof Class/Division (and Zone) Installations
In North America, explosion-proof installation requirements are governed primarily by NFPA 70 National Electrical Code (NEC), Articles 500 through 506, along with supporting standards such as NFPA 497, 499, 82, and 30.
One of the most important considerations is cable selection and cable protection.
For Class I, Division 1 fixed installations, cable requirements are strict. Cabling must be of an approved type and protected from physical damage. If the cable is not integral to the equipment, it must typically be either MC-HL cable with suitable protection or armored cable. The choice often depends on the compatibility of the cable and connectors with the equipment being installed. The adequacy of cable protection is ultimately at the discretion of the local inspector.
Division 1 installations also require the use of an approved cable gland. The gland may be supplied as part of the equipment or sourced separately, but it must carry the appropriate approval for the hazardous location. In many cases, this is a “potted’ gland that is sealed during installation.
For Class I, Division 2 installations, cable and gland requirements are much less restrictive. There is no specific requirement for additional cable protection beyond good installation practices. However, the cable should be suitable for the environment and be outdoor “tray-rated” at a minimum. The cable entry into the device is often accomplished using a conventional industrial cord grip or cable gland suitable for the location.
Installers should also verify that any openings that exist following installation must be properly sealed. For Division 1 installations, stopping plugs must be approved for the hazardous location and carry the appropriate rating. This information is typically laser-etched or permanently marked on the plug itself.
Read my interview about explosion-proof cameras and some key considerations when deploying them in hazardous environments.
ATEX and IECEx Installations
Businesses need to prioritize workplace safety. Putting the right safety systems and protocols in place protects your employees and helps ensure your other resources aren’t compromised.
For ATEX and IECEx equipment installations, the primary installation standard is IEC 60079-14. This standard does not differ across the various rating subsets.
Unlike the North American Class/Division system, IEC 60079-14 requirements are less strict.
Cables must:
- Be suitable for the intended environment.
- Have a sheath material capable of withstanding the expected environmental conditions.
- Be adequately supported throughout the installation.
- Be protected from mechanical damage.
Depending on the application, additional protection or more robust cable types may be required.
As with Class/Division installations, any unused openings in the equipment must be sealed using appropriately certified stopping plugs. These plugs must carry a rating suitable for the hazardous location and are typically laser-etched directly on the device.
Final Considerations
While the equipment itself may be certified for use in a hazardous location, proper installation is equally important. Proper installation helps ensure hazardous area equipment remains compliant throughout its service life. Factors such as cable selection, grounding, mounting methods, and approved cable entry devices help maintain the integrity of the installation and ensure compliance with applicable standards.
For help selecting the right explosion-proof equipment, contact IVC’s technical sales team at 617-467-3059 or get in touch. We’ll ensure the equipment and installation are appropriate for your hazardous location.
Below are answers to some of the most common questions about hazardous area equipment installation and compliance.
FAQs
What is the difference between Class I Division 1 and Division 2 installations?
Division 1 and Division 2 differ mainly in cable and gland requirements. Division 1 cable must be an approved type, protected from physical damage, typically MC-HL cable with suitable protection or armored cable, and installed with an approved cable gland. Division 2 is less restrictive: the cable should be at least outdoor-rated, and a conventional cord grip or gland is usually sufficient.
What cable is required for hazardous location equipment?
Cable requirements scale with the classification. For Class I, Division 1 fixed installations, cable must be an approved type and protected from physical damage, typically MC-HL cable or armored cable. The adequacy of that protection is ultimately at the discretion of the local inspector.
What standard governs ATEX and IECEx installations?
IEC 60079-14 governs both ATEX and IECEx installations and does not vary across rating subsets. Its requirements are less strict than the North American Class/Division system, but cables must still be suitable for the environment, adequately supported, and protected from mechanical damage.
Do hazardous location cameras need secondary fall protection?
Yes. Equipment, including PTZ cameras, should always have a secondary retention method in case the primary mount fails. This is typically achieved with a safety lanyard or cable rated for the load, along with a mounting structure designed to resist vibration, wind, and process-related movement.
What are the grounding requirements for hazardous area equipment?
Hazardous-area equipment is required to have an external grounding terminal. The manufacturer’s installation manual should specify the minimum wire gauge and grounding requirements, and those specifications should always take precedence over general grounding practice.
About the Author: Bill Richards is the co-founder and Vice President of Operations at Industrial Video & Control (IVC). He leads the company’s hardware engineering efforts and has over 25 years of experience developing products for hazardous areas. Among his accomplishments, Bill pioneered the industry’s first line of IP dome cameras certified for use in hazardous areas. Bill holds a bachelor’s degree in engineering from the University of Michigan.