Brass cable glands for explosive atmospheres must be certified to ATEX (Directive 2014/34/EU) or IECEx. The two protection concepts that apply to cable glands are Ex d (flameproof) for zones 1 and 2 (gas, vapour), and Ex e (increased safety). Certification routes through a Notified Body (CSA, DEKRA, SGS Baseefa, UL DEMKO), takes 6–14 months and costs €25,000–€60,000 per product family. This guide maps the regulatory landscape, IP rating overlay, brass alloy choice (CW614N is standard), and the documentation pack you need.
A standard brass cable gland — single-entry, double-entry, polymeric or marine grade — is straightforward engineering: a brass body with a compression seal that grips a cable and provides ingress protection. An ATEX/IECEx-certified brass cable gland is something altogether different: it must contain a potential ignition source (explosion) inside its body and prevent flame propagation to the outside atmosphere. The certification process reflects this safety-critical role.
The regulatory framework — ATEX vs IECEx
- ATEX (EU) — Directive 2014/34/EU. Mandatory for equipment placed on the market in the EU intended for use in potentially explosive atmospheres. Conformity assessment requires a Notified Body. Product carries the Ex hexagon mark.
- IECEx (international) — IEC 60079 family of standards. Voluntary international certification scheme accepted in 30+ countries outside the EU. Australia, Canada (in combination with CSA), Brazil, GCC, parts of Asia.
- UKCA (UK) — post-Brexit equivalent of ATEX. Largely harmonised with ATEX requirements but issued by UK-Approved Bodies.
Zones & categories
| Zone | Risk profile | Equipment category |
|---|---|---|
| Zone 0 (gas) | Explosive atmosphere present continuously or for long periods | Cat 1 — very high level of protection |
| Zone 1 (gas) | Explosive atmosphere likely to occur in normal operation | Cat 2 — high level of protection (most cable glands) |
| Zone 2 (gas) | Explosive atmosphere not likely; if occurs, only briefly | Cat 3 — normal level of protection |
| Zone 20 (dust) | Combustible dust cloud present continuously | Cat 1D |
| Zone 21 (dust) | Dust cloud likely in normal operation | Cat 2D |
| Zone 22 (dust) | Dust cloud not likely in normal operation | Cat 3D |
Protection concepts for cable glands
- Ex d (flameproof, IEC 60079-1) — The gland body is built strong enough to contain an internal explosion without rupturing, and any flame path through the gland is too narrow + too long to allow flame propagation outward. Standard for petrochemical, offshore oil & gas, hydrogen process plants. Brass body, machined to tight flame-path tolerance per the standard.
- Ex e (increased safety, IEC 60079-7) — Construction techniques eliminate the possibility of ignition inside the gland during normal service. Common on terminal boxes and motor terminations. Brass body with extra clearances and engineered insulation paths.
- Ex tb / tc (dust-tight enclosures, IEC 60079-31) — Sealed against dust ingress for dust-explosion zones. Common in flour mills, sugar plants, pharmaceutical powder handling.
IP rating overlay
ATEX certification does not by itself specify ingress protection; that's a separate IEC 60529 IP rating. Brass cable glands typically combine ATEX + IP66 / IP68. The IP rating is achieved by elastomer compression seals; the ATEX rating is achieved by flame-path geometry, dimensional tolerance, and brass body strength.
Material choice
- CW614N (CuZn39Pb3) brass — the workhorse alloy for ATEX cable glands. Good machinability (95% reference), adequate mechanical strength, accepts plating.
- CW617N (CuZn40Pb2) — alternative; lower lead grade for RoHS-sensitive applications.
- Brass + nickel plating — preferred for offshore / marine ATEX applications (chloride resistance).
- Stainless steel 316L — for ATEX cable glands in very-aggressive chemical environments where brass would corrode. Considerably higher cost.
Certification process
- Engineering design to the IEC 60079 series — flame path length, gap dimension, body wall thickness, fastener torque envelope
- Pre-assessment with a Notified Body (CSA Sira, DEKRA, SGS Baseefa, UL DEMKO etc.). Cost: €3,000–€8,000.
- Type testing — internal explosion test, flame-transmission test, pressure cycle test, mechanical impact (IK 07–IK 10), ingress test for IP rating. Cost: €15,000–€40,000.
- Quality system assessment — Notified Body audits the factory ISO 9001 + ATEX-specific Quality Assurance Notification (QAN). Cost: €5,000–€8,000.
- Certification issued — Ex certificate with unique number; product appears in IECEx online certificate database.
- Annual surveillance — Notified Body returns yearly to verify the QAN remains in force. Cost: €3,000–€6,000/year.
Realistic time + cost
| Phase | Time | Cost (EUR) |
|---|---|---|
| Engineering design + drawings | 2–3 months | internal |
| Pre-assessment | 1–2 months | €3,000–€8,000 |
| Type testing | 3–6 months | €15,000–€40,000 |
| QAN factory audit | 1–2 months | €5,000–€8,000 |
| Certification issue | 1 month | incl. above |
| TOTAL initial | 6–14 months | €23,000–€56,000 |
| Annual surveillance + cert maintenance | — | €3,000–€6,000/year |
Documentation pack you'll need
- Engineering drawings + 3D CAD with declared flame-path dimensions
- FMEA (Failure Mode and Effects Analysis) per IEC 60812
- Material certificates per EN 10204 Type 3.1 for the brass body
- Elastomer compatibility data for the IP seal
- Test plan and prototype samples
- QAN / ISO 9001 + ATEX-specific quality procedures
Sources & references
- ATEX Directive 2014/34/EU (EUR-Lex)
- IECEx — International electrotechnical commission scheme
- IEC 60079 series — explosive atmospheres standards
- IEC 60529 — IP rating standard
- Brassland custom brass cable glands
- CW614N alloy datasheet
Frequently asked questions
What does ATEX certification mean for a brass cable gland?
What is the difference between ATEX and IECEx?
Why is brass used for hazardous-area cable glands?
Sources & references
Hazardous-area references:
Last reviewed: June 2026. Standards and regulatory references are checked at each review.