IEC 60079-0 Edition 8 – Key Changes

1. Ambient Temperature Marking

• The standard ambient temperature range changes from −20 °C to +40 °C to −20 °C to +60 °C.
• Ambient temperature marking is now mandatory on all equipment.
• Any alternative ambient ranges must be supported by formal Specific Conditions of Use.

2. Expanded Electrostatic Risk Requirements

Electrostatic protection requirements have been significantly strengthened.

The new requirements cover:

• Structural plastics
• Coatings
• Paints
• Labels
• Composite materials
• Surface finishes

Additional requirements include:

• Electrostatic bonding
• Brush discharge mitigation
• Improved assessment of charge accumulation and discharge mechanisms

These changes are particularly important for:

• Zone 0 equipment
• EPL Ga equipment
• Group IIC applications
• Hydrogen atmospheres

3. External Conductive Parts on Portable Equipment

Edition 7 allowed certain risks to be managed through Specific Conditions of Use (X marking).

Edition 8 removes this approach for many portable products.

Manufacturers must now demonstrate compliance through:

• Maximum capacitance testing
• Transferred charge testing

If the equipment fails these tests, design modifications are required. User instructions alone are no longer sufficient.

4. Thermal Protection for Rotating Equipment with Auxiliary Cooling

For motors and other rotating equipment using forced-air or liquid cooling:

• Independent thermal protection is now mandatory.
• Temperature sensors or equivalent protective devices must automatically shut down the equipment if cooling fails.

Reliance on operator intervention is no longer acceptable for newly certified equipment.

5. Factory Wiring Between Enclosures (New Clause 19)

Clause 19, previously reserved for future use, has been fully introduced.

Factory-installed wiring between certified enclosures is now considered part of the certified equipment and must be:

• Designed
• Tested
• Documented
• Included within the certification scope

This is particularly relevant for:

• Skid-mounted systems
• Multi-enclosure assemblies
• Instrumentation systems
• Control panels

6. Enhanced IP Protection Requirements for Socket-Outlets and Connectors

Ingress Protection (IP) requirements have been expanded.

Manufacturers must now demonstrate the required IP rating:

• When connectors are mated
• When connectors are unmated (where applicable)
• When protective covers or caps are fitted

The complete connector system must be evaluated rather than relying solely on supplier IP ratings.

7. Changes to the Marking Philosophy

The philosophy behind equipment marking has changed.

Previous practice:

• Advisory warnings could sometimes replace formal conditions.

Edition 8:

• Whenever safe operation depends on installation or user actions, these requirements must be formalized as Specific Conditions of Use (X marking).

This reduces reliance on advisory text and improves consistency during installation and inspection.

8. Digital Marking

Edition 8 introduces the possibility of using:

• QR codes
• Other machine-readable digital markings

These supplement, but do not replace, mandatory equipment markings.

9. New Battery Technologies

The scope of the standard has been expanded to include additional battery chemistries, including:

• Sodium Nickel Chloride batteries

reflecting their increasing use in hazardous-area applications.

10. Cybersecurity Considerations

For the first time, the standard acknowledges cybersecurity for connected Ex equipment.

Although no mandatory technical requirements are introduced yet, the inclusion signals the future direction of the IEC 60079 series.

11. Stronger Lifecycle and System-Level Approach

Edition 8 places greater emphasis on:

• Equipment behaviour throughout its service life
• Interaction with surrounding equipment
• System-level safety
• Long-term maintenance of explosion protection

The standard increasingly views Ex equipment as part of an integrated installation rather than as isolated certified products.

Summary of the Main Changes

No.	Key Change
1	Mandatory ambient temperature marking (+60 °C standard range)
2	Expanded electrostatic risk requirements
3	New testing requirements for conductive parts on portable equipment
4	Mandatory automatic thermal protection for auxiliary-cooled rotating equipment
5	New requirements for factory wiring between certified enclosures (Clause 19)
6	Enhanced IP verification for socket-outlets and connectors
7	Revised marking philosophy with increased use of formal Specific Conditions of Use (X marking)
8	Introduction of digital marking (QR codes and machine-readable information)
9	Inclusion of new battery technologies
10	Recognition of cybersecurity considerations
11	Stronger lifecycle and system-level safety philosophy

Keep up the good work!

Arpad
veress@exprofessional.com