Can standard industrial equipment be used in Zone 2 without Ex certification?

As a rule, no. Equipment with its own potential ignition source that is newly installed in Zone 2 must be suitable for that zone: in the EU at least ATEX category 3 (EPL Gc), elsewhere Ex-certified equipment with EPL Gc or better. The law leaves a narrow exception for cases a documented risk assessment justifies with an equivalent level of safety, but it is not a route to use ordinary equipment because it is cheaper or quicker to buy.

Short answer

• Directive 1999/92/EC requires category 1, 2 or 3 equipment in Zone 2, selected on the basis of the equipment directive (94/9/EC, now 2014/34/EU), unless the explosion protection document, based on a risk assessment, states otherwise.
• UK guidance (HSE L138) says that flexibility must be justified and recorded, must give a level of safety equivalent to the regulations, and cannot be used to sidestep the duties of suppliers and importers of equipment.
• Items with no ignition source of their own (a pipe, a vessel wall, a passive label) are not "equipment" in the ATEX sense and need no marking.
• Equipment already in use before July 2003 may continue in use if the employer has assessed it. New equipment, and in UK guidance also second-hand equipment and stock spares first brought into use after 1 July 2003, has to meet the equipment regulations.
• IEC 60079-14 has long restricted uncertified equipment to cases where suitable certified equipment cannot be obtained, with the justification recorded in the verification dossier.

Why "it does not spark" is not enough

Zone 2 is the lowest gas zone, but it is still a place where an explosive atmosphere can occur, briefly and rarely, in normal operation. EPL Gc equipment is designed to be safe in normal operation and in regular expected occurrences. That does not happen by accident in standard equipment:

• Hot surfaces. Ordinary motors, drives, power supplies and lamps have no temperature class. A surface that is harmless in a factory hall can exceed the auto-ignition temperature of the gas present.
• Hidden sparking. Relays, switches, contactors, brushed motors and plug connectors arc during normal switching.
• No verified enclosure or terminals. Clearances, creepage distances, terminal security and sealing in Ex ec equipment are tested; in standard products they are not assessed against gas ignition.
• No controlled documentation. Without a certificate there are no conditions of use, no ambient temperature range and no basis for inspection under IEC 60079-17.

An engineer can sometimes show that a simple item, such as a brushless motor running cool, would probably not ignite gas. But "probably" is the weak point: an equivalent level of safety needs the same evidence a certification would provide, and the person signing the assessment carries the responsibility for it.

What the law and the standards actually allow

EU workplaces (Directive 1999/92/EC). Annex II, Part B, lists the categories per zone: category 1, 2 or 3 for Zone 2. The same paragraph allows another approach where the explosion protection document, based on a risk assessment, states otherwise. National guidance treats this as a narrow derogation. The UK Approved Code of Practice L138 explains it in these terms: the decision must be justified and recorded, show equivalent safety, and not be used to avoid the equipment regulations. Its guidance gives the intended cases: equipment taken temporarily into a zone with other effective precautions (for example isolating the source of release), work where people can be kept out of the hazardous area, or where equipment of the required category is simply not available and a lower category is combined with other protective measures. It also confirms that new equipment for hazardous places is in most cases achieved simply by selecting equipment of the right category after area classification.

EU equipment (Directive 2014/34/EU). "Equipment" in the directive means items that can cause an explosion through their own potential sources of ignition. Something with no ignition source of its own is outside the directive, which is why pipes and passive parts carry no ATEX marking. Electrical equipment almost always has its own ignition sources.

Existing equipment. L138 allows products already in use before July 2003 to continue in use if the employer has assessed them and can show the fire and explosion risks are eliminated or reduced so far as reasonably practicable. HSE operational guidance adds that spares ready to use without substantial modification and second-hand equipment can be used where the DSEAR risk assessment justifies it, while L138 states that second-hand equipment and stock spares brought into use after 1 July 2003 must meet the equipment regulations unless they were already in use in the EU before then.

IEC 60079-14. In the 2007 edition, equipment without a certificate (other than simple apparatus in intrinsically safe circuits) could be selected only where suitable certified equipment was not obtainable, and the justification had to be recorded in the verification dossier by the user, manufacturer or a third party. The 2024 edition contains a clause titled conditions of control for exceptional circumstances; check its exact wording for your project.

Practical options instead of standard equipment

Where a standard item seems unavoidable, ask whether it can be placed outside the zone, whether the zone can be reduced by better ventilation or containment, or whether gas detection can isolate it reliably before gas reaches it. Each of these needs its own assessment.

Common mistakes

• Treating Zone 2 as "almost safe". Gas is expected there only rarely, but the equipment must still not ignite it when it comes.
• Using an IP66 rating as a substitute. IP ratings test dust and water ingress, not gas ignition.
• Writing a one-line justification in the explosion protection document to cover a cost decision.
• Forgetting mechanical equipment. Fans and pumps have their own ignition sources and need category 3 or better too; see do pumps, gearboxes and fans need ATEX certification?

Related on excodex

• Ex ec, Ex nA and Ex nR: protection for Zone 2
• ATEX explained: the two EU directives 2014/34/EU and 1999/92/EC in plain language
• ATEX equipment categories 1, 2 and 3 and how they relate to EPLs
• Is an IP67 enclosure the same as an explosion-proof enclosure?
• Standards spaces: ATEX 1999/92/EC, ATEX 2014/34/EU, IEC 60079-14

Standards and further reading

• Directive 1999/92/EC, Annex II, Part B, selection of equipment by category: legislation.gov.uk
• Directive 2014/34/EU, Article 2, definitions of equipment and manufacturer: legislation.gov.uk
• DSEAR 2002 (UK), Schedule 3, equipment selection: legislation.gov.uk
• HSE L138, DSEAR Approved Code of Practice and guidance (selection of equipment, use of the risk assessment derogation): hse.gov.uk
• HSE, relationship between DSEAR and the equipment regulations: hse.gov.uk
• IEC 60079-14, design, selection and installation; 2007 text as AS/NZS 60079.14:2009: archive.org

This article is general technical information prepared by the excodex editorial team. It does not replace the applicable standards, the equipment certificates and instructions, national regulations or the assessment of a competent person.