Specifications

K
K14
Parker Hannifin Corporation
Pneumatic Division
Wadsworth, Ohio
www.parker.com/pneumatics
Pneumatic Actuator Products
Air Motors
Catalog 0900P-E
ATEX
Introduction to the ATEX directive
Explosive Atmospheres
Directive 94/9/EC defines an explosive atmosphere as a mixture of:
a) flammable substances – gases, vapors, mists or dusts
b) with air
c) under specific atmospheric conditions
d) in which, after ignition has occurred, combustion spreads to the
entire flammable mixture
(NB: with regard to dust, it may be that not all dust is combusted
after ignition has occurred)
An atmosphere with the potential to become an explosive
atmosphere during operating conditions and/or under the influence of
the surroundings is defined as a potentially explosive atmosphere.
Products covered by directive 94/9/EC are defined as intended for
use in potentially explosive atmospheres.
Harmonised European ATEX Standard
The European Union has adopted two harmonised directives in the
field of health and safety. The directives are known as ATEX 100a
and ATEX 137.
Directive ATEX 100a (94/9/EC) lays down minimum safety
requirements for products intended for use in potentially explosive
atmospheres in European Union member states. Directive ATEX
137 (99/92/EC) defines minimum requirements for health and safety
at the workplace, for working conditions and for the handling of
products and materials in potentially explosive atmospheres. This
directive also divides the workplace into zones and defines criteria
by which products are categorized within these zones.
The table below describes the zones in an installation where there is
a potential for explosive atmospheres. The owner of the installation
must analyse and assess the area in which the explosive gas/dust
mixture may occur, and if necessary must divide it into zones. This
process of zoning then allows the correct plant and equipment to be
selected for use in the area.
The ATEX directive has been in force throughout the European
Union since 1 July 2003, replacing the existing divergent national
and European legislation relating to explosive atmospheres.
Please note that for the first time, the directive covers mechanical,
hydraulic and pneumatic equipment and not just electrical equipment
as before.
With regard to the Machinery Directive 98/37/EC, note that a
number of external requirements in 94/9/EC refer to hazards arising
from potentially explosive atmospheres, where the Machinery
directive only contains general requirements relating to explosion
safety (Annex I
1.5.7).
As a result, directive 94/9/EC (ATEX 100a) takes precedence over the
Machinery directive with regard to explosion protection in potentially
explosive atmospheres. The requirements in the Machinery directive
are applicable to all other risks relating to machinery.
Zones Presence of Potentially Explosive Atmosphere Type of risk
Gas Dust
G D
0 20 Present continuously or for long periods Permanent
1 21 Likely to occur in normal operation occasionally Potential
2 22 Not likely to occur in normal operation but, if it does occur, Minimal
will persist for a short period only
Zone 1
Category 2
Zone 2
Category 3
Zone 0
Category 1