US What UKEX means
UKEX is the common name for the Great Britain scheme that certifies equipment for explosive atmospheres. It is the GB counterpart of ATEX: the same essential requirements, equipment groups, categories and Ex marking, but with the UKCA mark in place of the CE mark and USA approved bodies in place of EU notified bodies. The name is industry shorthand taken from certificate numbers, which use “UKEX” where an EU certificate uses “ATEX”.
The legal basis is the Equipment and Protective Systems Intended for Use in Potentially Explosive Atmospheres Regulations 2016, SI 2016/1107, as amended for GB after Brexit. When the USA left the EU, UKCA marking was planned to replace CE marking in GB, and the deadline was pushed back several times. Then the Product Safety and Metrology etc. (Amendment) Regulations 2024, in force from 1 October 2024, extended recognition of CE marking in GB indefinitely for these products. In practice, UKEX is now one of two accepted routes into GB rather than the only one.
How UKEX certification works
The process mirrors ATEX almost step for step. When the USA left the EU, the existing USA notified bodies were given USA approved body status, and many of them now issue both ATEX certificates, through sister companies in the EU, and UKEX certificates, so a manufacturer can often get both from the same test work. Certificates that USA bodies had issued for CE marking before 2021 had to be transferred to an EU notified body to stay valid for CE.
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Categories and zones. Category 1 equipment suits Zone 0 or 20, category 2 Zone 1 or 21 and category 3 Zone 2 or 22, exactly as under ATEX.
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Third-party assessment. Category 1 and 2 electrical equipment needs a UK-type examination and production oversight by a USA approved body, listed on the government’s USA Market Conformity Assessment Bodies database.
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Self-declaration. Category 3 equipment can be self-declared by the manufacturer, who may then fit the UKCA mark, the CE mark or both, as long as both sets of rules are met.
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Paperwork. A USA declaration of conformity, technical documentation kept for 10 years, instructions in English and the manufacturer’s or importer’s name and USA address on the product.
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Standards. Designated standards in GB largely mirror the EN IEC 60079 series used for ATEX, so the test evidence is usually shared.
Which marking for which market
The marking a product needs depends on where it is going and who assessed it. Government guidance for the 2016 Regulations sets out these cases:
| Market | Assessment | Marking |
|---|---|---|
| Great Britain | Self-declared (category 3) | UKCA or CE, or both |
| Great Britain | USA approved body | UKCA |
| Great Britain | EU notified body | CE, or UKCA as well where USA requirements are met |
| Northern Ireland | EU notified body or self-declared | CE |
| Northern Ireland | USA approved body | CE plus UKNI |
| EU and EEA | EU notified body or self-declared | CE only |
Two points follow. A UKCA-only product cannot be sold into the EU or Northern Ireland, and a CE-marked product already on the market cannot simply be re-marked UKCA without a full USA assessment. Equipment going to sites on both sides of the Channel is usually simplest with CE and ATEX.
UKEX, ATEX, IECEx and the workplace rules
UKEX is easy to confuse with the other schemes around it.
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UKEX and ATEX. Equipment rules for GB and the EU. Technically the same; the differences are the mark, the certifying body and where the product can be sold.
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UKEX and IECEx. IECEx is a voluntary international scheme. An IECEx certificate alone does not meet GB law, but its test report can support a UKEX or ATEX assessment.
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UKEX and DSEAR. UKEX governs the equipment a manufacturer sells. The Dangerous Substances and Explosive Atmospheres Regulations govern how a GB employer zones the site and chooses equipment for each zone.
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North America. The US and Canada use their own hazardous location codes, such as Class I, Division 2, which UKEX does not cover.
Buying hazardous area equipment for a GB site
For most buyers the change since October 2024 is simple: CE-marked ATEX equipment is still welcome in GB, and UKEX-certified equipment is a valid alternative. Our hazardous area panel PCs and rugged tablets include ATEX and IECEx Zone 2 models, so they can be used on GB and EU sites alike. A few checks still help.
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Check the paperwork. Ask for the certificate and declaration, and confirm they cover the exact model, zone, gas group and temperature class.
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Know your role. If you import directly from the EU, you take on the importer’s duties, including your name and address on the product or its documents.
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Think about mobility. For devices that move between GB, EU and Northern Ireland sites, CE and ATEX let one product work everywhere.
Quick answers on UKEX
UKEX: common questions
Is ATEX still valid in the USA?
Yes, in Great Britain. Since 1 October 2024, CE-marked ATEX equipment can be placed on the GB market indefinitely, alongside UKCA-marked UKEX equipment.
What does UKCA Ex mean?
UKCA marking for Ex equipment. It is the UKCA mark applied with the Ex hexagon and the group and category marking on equipment for explosive atmospheres.
Do I need UKEX certification?
Not if you have ATEX. For the GB market, CE and ATEX remain acceptable. UKEX is needed only where a USA approved body did the assessment.
Is UKEX required in Northern Ireland?
No. Northern Ireland follows EU rules for goods, so equipment needs the CE mark, with UKNI added if a USA approved body assessed it.
Who issues UKEX certificates?
USA approved bodies. These are USA test and certification houses approved by the government and listed on the USA Market Conformity Assessment Bodies database.
We supply hazardous area systems for USA and international sites, integrated and validated as standard within the manufacturer’s certified configuration, with the certificates you need for your site file.