Published February 2025 • Installation Practices • 6 min read

Choosing Cable Glands for Hazardous Areas

Cable glands are a small component that carry significant certification risk. If the wrong gland type is installed, the enclosure rating collapses, and auditors will question the entire installation. Use this quick workflow to pick the right gland, verify markings, and document the installation for both gas and dust hazardous areas.

Start with Protection Method and Ingress Needs

Step 1: Match the Protection Concept

  • Ex d / Flameproof: Requires flameproof barrier or compound filled glands when cables are not tightly filled. Choose glands with tested flamepaths for your gas group and temperature rating.
  • Ex e / Increased Safety: Use compression or displacement seal glands that maintain IP rating. Barrier seals are only required if cable voids cannot be filled.
  • Ex t / Dust: Confirm the IP rating meets enclosure requirements (often IP6X). Look for “tD” marking and surface temperature rating.
  • Pressurized panels: Ensure glands can hold the enclosure pressure and include a leakage rate in documentation.

Confirm Certificate Details

Every gland should ship with a certificate of conformity or a QR code link to the latest IECEx or ATEX certificate.

  • Verify marking format (e.g., Ex db IIC Gb, Ex eb IIC Gb, Ex tb IIIC Db).
  • Check temperature range—especially if the gland will see heater traces or sunlight.
  • Match thread type and tolerance to the enclosure entry (metric, NPT, BSPP).

Know Your Sealing Types

Barrier Glands

Include epoxy or compound that encapsulates individual conductors. Required when cable fillers are not tight or when stopping power is needed. Allow extra cure time in schedules.

Compression Glands

Rely on elastomeric seals around the outer sheath. Faster to install, but only acceptable when cable filler is tight and certified for the protection concept.

Installation Checklist

  • Inspect cable for sheath damage before stripping.
  • Maintain minimum thread engagement (typically five full threads for flameproof entries).
  • Torque to manufacturer specification; note the value in the inspection record.
  • Check for static bonding requirements via locknuts or serrated washers.
  • Apply thread sealant only if permitted by both enclosure and gland certificates.
Documentation Tip: Capture gland type, manufacturer, certificate number, and torque in the equipment register. When auditors see complete data, they spend less time sampling hardware onsite.

Common Mistakes to Avoid

  • Mixing gland materials with enclosure metals, causing galvanic corrosion.
  • Using industrial glands on cable trays entering hazardous areas without barrier seals.
  • Leaving drain or breather devices open without mesh protection.
  • Skipping secondary retention in vibrating applications.

Thoughtful cable gland selection keeps your Ex certification intact and prevents field rework. If you need help reviewing vendor data sheets or matching glands to cable constructions, HazloLabs can review the bill of materials and deliver a short approval matrix for your installers.