IEC 60079-45:2025

Overview - IEC 60079-45:2025 (Explosive atmospheres)

IEC 60079-45:2025 specifies minimum safety, construction and test requirements for electrical ignition systems for spark‑ignited reciprocating internal combustion engines intended to operate in or adjacent to explosive atmospheres. The standard targets systems and components that provide Equipment Protection Level (EPL) Gc for equipment groups IIB+H2, IIB or IIA, and applies to systems with secondary voltages ≤ 60 kV. It covers stationary engines and mobile machinery where the engine can be a potential ignition source (e.g., gas compressors, generators, forklift trucks, pumps) and supplements IEC 60079-0 and ISO/IEC 80079-41.

Key topics and requirements

• Scope and exclusions: Applies only to ignition systems/components for stationary reciprocating engines and some mobile machinery; excludes breaker-point or magneto systems, road vehicles, and low-voltage parts outside the ignition system.
• Safety objectives: Enhance personnel safety by mitigating ignition risks in hazardous areas and ensuring ignition system parts meet EPL Gc.
• Design and construction: Requirements for ignition coils, secondary leads (flexible and rigid), spark plugs, terminations, enclosures and spark containment features.
• Spark controls:
  • Spark containment - prevent release of hot particles/gases to hazardous atmospheres.
  • Spark prevention/detection - design and protective measures to avoid unintended ignition.
• Testing program: Detailed test procedures and performance tests such as abrasion, chemical compatibility, vibration, flashover, spark plug gas‑tightness, dielectric withstand and pull/cut tests for leads and terminations.
• Marking & documentation: Ex certificate requirements, warning markings, manufacturer’s instructions, installation drawings, commissioning checklists and maintenance recommendations.
• Conformity: Where this part conflicts with IEC 60079‑0 or ISO/IEC 80079‑41, IEC 60079‑45 takes precedence for ignition-system specifics.

Practical applications - who uses this standard

• Manufacturers of ignition coils, secondary leads, spark plugs and ignition control units developing EPL Gc equipment.
• Certification bodies assessing compliance for use in hazardous (classified) locations.
• Design and safety engineers specifying ignition systems for gas compressors, power generators, pumps, forklifts and other machinery where engines are potential ignition sources.
• Installers and maintenance personnel following manufacturer installation, commissioning and maintenance requirements to preserve safe operation.

Related standards

• IEC 60079-0 - General requirements for equipment in explosive atmospheres.
• ISO/IEC 80079-41 - Additional requirements for non-electrical equipment; supplemented/modified by this document.
• ANSI/UL 122001 - Served as a basis during development (regional reference).

Keywords: IEC 60079-45, explosive atmospheres, electrical ignition systems, internal combustion engines, EPL Gc, spark containment, spark prevention, hazardous areas, ignition coils, secondary leads, IEC 60079-0.