Overview
IEC 60981:2019 - Extra heavy-duty electrical rigid steel conduits (EHDERS) - is the third edition international standard that defines requirements for extra heavy‑duty electrical rigid steel conduits, couplings, nipples and elbows, including thread forms and protective coatings. It applies to conduits used in electrical installations - including communications and fibre‑optics - and replaces the 2004 edition. The standard is explicit that it does not apply to the conduits covered by IEC 60423.
Key topics and technical requirements
- Scope and components: Requirements for EHDERS conduits, couplings, nipples and 90° elbows; thread specifications for these parts.
- Dimensions & threads: Specified conduit wall thicknesses, diameters and thread forms to ensure interchangeability and mechanical integrity.
- Protective coatings: Detailed rules for zinc coatings and provisions for alternative exterior coatings (new in 2019). Annex B provides test methods for evaluating alternative corrosion‑resistant coatings.
- Coating tests: Inclusion of an elasticity test for organic coatings and other test programs (e.g., salt spray, UV, and oven conditioning referenced via ISO/IEC methods) to verify adhesion and durability.
- Mechanical and manufacturing requirements: Welding, cleaning, chamfering, coupling dimensions, ductility and bending performance, and marking requirements for traceability.
- Test methods & annexes: Normative Annex A covers zinc thickness testing; Annex B contains a new, systematic test program for alternative exterior coatings. Normative references include IEC 60695‑11‑3, IEC 61950, ISO 9227, ISO 4892‑2, among others.
Practical applications and users
Who uses IEC 60981:2019:
- Conduit and fittings manufacturers - to design and certify EHDERS products that meet international performance and interchangeability requirements.
- Electrical engineers and specifiers - to select compatible conduits and fittings for robust electrical and communications installations.
- Procurement and compliance teams - to set procurement criteria and verify supplier conformity.
- Certifiers and test laboratories - to perform the standardized coating, mechanical and thread tests required by the standard.
Typical applications:
- Heavy‑duty electrical installations in industrial and commercial buildings.
- Conduit runs that enclose power, communications and fibre‑optics cabling where enhanced mechanical protection and corrosion resistance are required.
Related standards
IEC 60981:2019 provides manufacturers, engineers and compliance teams with a clear, updated technical framework for specifying and testing extra heavy‑duty steel conduit systems, including modern options for corrosion protection and validated test procedures for alternative coatings.
