ATEX certification coding explained

On July 1, 2003 the ATEX Directive became mandatory in Europe and governed by European law for all electrical and mechanical
equipment used in potentially explosive atmospheres. After that date, products without ATEX certification will be illegal
on the European market, and connot feature the new CE mark.

NOTE: This document is intended only as a primer for ATEX and CE marking. Please google ATEX certification
or visit a very informative page on ATEX at sensorland.com

For CE marking, as well as compliance with ATEX, all hazardous area
equipment must comply with any other applicable directives. Currently,
the CE mark does not prove ATEX compliance as some hazardous area
equipment may be CE marked through compliance with other mandatory
directives.

Under ATEX, manufacturers must design and test components to prevent
or minimise the risk of explosion due to the production or release of
explosive atmospheres. Essentially, manufacturers must consider every
possible electrical or non-electrical source of ignition. And, at the same
time, consider all potentially hazardous environments a product could
operate in; the different ways it could be applied and the technical ability
of the person using the product.

Getting products approved

As with all new regulations, all new products must be assessed and all
existing products reassessed. There are two elements to gaining product
approval – Product Type Approval (testing and assessment) and Production
Control (quality systems in manufacture).

The former involves compliance with the Essential Health and Safety

Requirements (EHSRs) described in Annex II of the directive. Electrical
equipment is well covered, but few standards cover non-electrical
equipment. Production Control involves a Quality Assurance type
procedure often with the responsible manufacturer being audited by
a Notified Body for compliance with the relevant annex dependent on
the type of equipment and QA system currently in place.

The route to compliance with EHSRs will see most manufacturers choosing
to prove conformity with the latest edition of the harmonised standards for
electrical equipment for use in potentially explosive atmospheres. For all
equipment this will require testing and production of test reports. For the
higher risk equipment – electrical categories I and 2 and mechanical
category I – this testing must be conducted by a Notified Body, normally
culminating with the issue of an EC Type Examination Certificate. The
details of this certificate must also be marked on the equipment.

Protection zones and categories

Manufacturers must also supply other evidence of compliance such as proof
of a consideration of issues including general electrical safety and EMC.
New standards are currently being introduced almost every month, so
working with a chosen Notified Body at each stage of the process will
help manufacturers keep abreast of current methodology and standards.

Under ATEX, all products must be categorised by the level of protection
they offer against the risk of becoming a potential source of ignition in
an explosive atmosphere. Defined categories for equipment conformity
are divided between surface and mining applications. The ‘Use Directive’
describes zones to reflect the explosion risk.

The ATEX Directive makes Notified Body involvement mandatory in both
equipment assessment and monitoring of production for equipment for
use in Zone 0 areas (highest risk) and for equipment to be used in Zone
1 areas (medium risk). For equipment to be used in Zone 2 areas only
(least risk) the manufacturer has to maintain technical documentation
which includes evidence of testing and production control, although
a Notified Body is not necessarily involved.

ATEX certification coding example

CE – Ex – II – 2 – G – EEx – d – IIC – T4 – T amb

CE
This means CE mark permitted by the European Commission to show compliance with all EU directives applicable to a product.

Ex
Distinctive mark to show suitability for explosive atmospheres

II
Group II – surface industries
Group I – for use in mines

2
Equipment category

G
G = tested for gases
D = tested for dusts

EEx
EEx means equipment tested under the latest European Harmonised Standard for use in Explosive atmospheres

d
Certification Production concept
e.g. d(flameproof) to EN50018

IIC
Apparatus Group

T4
Temperature classification
T1 = 450 Deg.C
T2 = 300 Deg.C
T3 = 200 Deg.C
T4 = 135 Deg.C
T5 = 100 Deg.C
T6 = 85 Deg.C.

T amb
Ambient temperature range in service
(Standard between -20 and +40 Deg.C)


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