IECEx – INTERNATIONAL STANDARD FOR
EXPLOSIVE ATMOSPHERE EQUIPMENT
The International Electrotechnical Commission (IEC) standard
for explosive atmospheres (Ex) equipment, the IEC 60079
series, is now the international benchmark. It is used in 30+
IECEx member countries, including Australia, Brazil, China,
Great Britain, New Zealand, Canada and the USA.
While IECEx has been widely adopted, there are a number of
local regulations also in use. For example:
• NEC/CEC – US and Canada.
• ATEX – Europe
• InMetro – Brazil
• ANZEx – Australasia
NEC/CEC - North America
In the United States, equipment must meet the National
Electrical Code (NEC) ANSI/NFPA-70. Equipment can
be approved for divisions or zones. Equipment for use in
explosive atmospheres in Canada must meet the Canadian
Electrical Code (CEC) CSA C22.1.
The United States Occupational Safety and Health
Administration (OSHA) certifies Nationally Recognized
Testing Laboratories (NRTL), which test and certify to US
and Canadian standards. Examples include FM Global, TÜV
Rheinland, UL, and CSA.
North American standards bodies have adopted the IEC
standards. Approval for North America can be achieved by
submission and review of the IECEx documentation, with
additional testing to national deviations.
ATEX – The European Directives
Equipment for use in explosive atmospheres in Europe is
covered by Directive 94/9/EC (ATEX Equipment). The
term ATEX is taken from the directive title “Atmosphères
At the equipment technical level, IECEx and ATEX are very
similar. The standards used to meet ATEX are generally
European versions of the IEC IECEx standards. The ATEX
directive also defines equipment groups and categories, which
gives ATEX equipment additional label markings (compared
Intrinsically Safe (IS) Standards help guide
manufacturers, purchasers and users who design,
manufacture, select and operate equipment in
hazardous atmospheres. IS-certified products limit
the electrical and thermal energy generated, to a level
lower than that required to ignite a specific hazardous
These standards apply to all equipment – not just
communications equipment such as radios – that could
potentially generate electrical or thermal energy and ignite
flammable particles in the atmosphere.
Here’s a guide to help you to understand the jurisdictions
of the different standards. Note that industry and/or federal
regulation is also likely to influence the standards that apply,
and an experienced professional must always be consulted.