IEC 60079-0:2017

Overview

IEC 60079-0:2017 - Explosive atmospheres - Part 0: Equipment - General requirements - sets the baseline general requirements for the construction, testing and marking of Ex Equipment and Ex Components intended for use in explosive atmospheres. This seventh edition (replacing the 2011 edition) is a technical revision and incorporates interpretation sheets (April 2019, June 2019) and Corrigendum 1 (January 2020). The standard defines the standard atmospheric conditions under which Ex equipment is assumed operable:

• Temperature: −20 °C to +60 °C
• Pressure: 80 kPa to 110 kPa (0.8–1.1 bar)
• Air: normal oxygen content (typically 21 % v/v)

IEC 60079-0 also explains when additional testing or special considerations are required for operation outside these ranges, particularly for Types of Protection that rely on flame quenching (e.g., flameproof “d”) or energy limitation (intrinsic safety “i”).

Key Topics

The standard covers technical subjects that are essential for designers, manufacturers and certifying bodies:

• Equipment grouping (Group I, II, III) and selection for specific atmospheres
• Temperature classification and maximum surface temperatures, including measurement and limitation
• Material requirements for non‑metallic and metallic enclosures, and resistance to UV, thermal ageing and electrostatic charge
• Mechanical design: strength, fasteners, interlocks, bushings and entries (cable glands, blanking elements)
• Connection facilities: earthing/bonding, creepage/clearance and secure electrical connections
• Supplementary requirements for electric machines, switchgear, luminaires, plugs, batteries and handlights
• Ex Components: mounting, marking and certification requirements
• Testing and verification: type tests, thermal and impact tests, small component ignition tests and IP protection tests
• Documentation and marking requirements to demonstrate compliance

Applications

IEC 60079-0 is the foundational reference for designing and assessing equipment for hazardous areas and explosive atmospheres. Practical uses include:

• Development and certification of hazardous‑area electrical and electronic equipment
• Product design decisions for enclosures, materials and sealing to prevent ignition sources
• Test laboratory procedures and conformity assessment for Ex marking and type testing
• Specification and procurement of equipment for industry sectors such as oil & gas, mining, chemical processing, and grain handling
• Guidance on additional testing when equipment is intended to operate outside standard temperature, pressure or oxygen ranges

Who uses this standard

• Equipment designers and manufacturers of Ex Equipment and Ex Components
• Certification bodies and test laboratories performing type tests and assessments
• System integrators, facility engineers and maintenance teams specifying and installing hazardous‑area equipment
• Regulatory and compliance professionals aligning products with national and international hazardous‑area requirements

Related standards

IEC 60079-0 is the general part of the IEC 60079 series and is used together with specific Type of Protection standards such as IEC 60079-1 (flameproof “d”) and IEC 60079-11 (intrinsic safety “i”) for more detailed test and construction requirements.