You're here : Home > Products > ATEX & MTTFd > ATEX Directive

ATEX Directive

DESCASE and ATEX Directive

Lasted updated guideline published by European commisssion: Guide ATEX 2009
.pdf Pour ouvrir ce fichier vous aurez besoin deInstaller Foxit pdf ReaderInstaller pdf Acrobat Reader Taille : 1115.17 Ko

See article 3.7.2, page 11 and 12; it is specifyed:
Many common items are made from plastics (polymers) with very low electrical conductivity. These can become charged, e.g. if they are rubbed or if dust or a liquid flows over the surface. However, in most cases this may be controlled by the user, and if they are used in hazardous areas it shall be assessed and controlled according the requirements of relevant national or community legislation (e.g. directive 1999/92/EC). In any case the user of such equipment has to consider these ignition sources when undertaking a risk assessment in the workplace.
Examples are plastic containers used for transporting chemical, polyethylene pipes, buckets and chairs.
If the only source of electrostatic charging comes from the process, such items are not considered to have their own source of ignition and they are not in scope of directive 94/95/EC. In these cases they should not be Ex or CE marked according to directive 94/9/EC.

Body of DESCASE breathers are made of Polycarbonate. Please have a look on the link here after: » polycarbonate . This product has very good dielectric property.

For all of the reason here above, the DESCASE breathers do not enter in the scope of ATEX regulation and can be used everywhere.

Examples for equipment not covered by Directive 94/9/EC (page 33)
5.2.1. "Simple" products
For "simple" electrical products, European harmonised standards provide a good basis to assess the effectiveness of electrical ignition source and, consequently, to determine whether or not these can be considered effective or not.
In general, many simple mechanical products do not fall under the scope of Directive 94/9/EC as they do not have their own source of ignition (see chapter 3.7.2). Examples without own source of ignition are hand tools such as hammers, spanners, saws and ladders.
Other examples that in most cases have no potential ignition source are given below. However, the manufacturer will need to consider each item in turn with respect to potential ignition hazard to consider whether Directive 94/9/EC applies (see also chapter 3.7.3):
- clockwork time pieces; mechanical camera shutters (metallic);
- pressure relief valves, self-closing doors;
- equipment moved only by human power, a hand operated pump, hand powered lifting equipment, hand operated valves.
The issue of hand operated valves has also been discussed. Given that these will move slowly, with no possibility of forming hot surfaces, as discussed in section 3.7.3 they are not in scope of the Directive. Some designs incorporate polymeric parts, which could become charged, but this is no different from plastic pipes. Given that it is clear that the latter is outside of the scope of Directive 94/9/EC it has been accepted that such valves do not fall within scope.
Some manufacturers have argued that their valves are specially adapted for ATEX, in that they have either selected more conductive polymers, or taken steps to ensure that no metal parts could become charged because they are unearthed. Other manufacturers state that all their valves meet this requirement simply by the way they are constructed, and they see no distinction from valves used to process non-flammable materials. To avoid confusion between those who claim correctly that their valves have no source of ignition, and are out of scope, and those who claim that they have done some very simple design change and wish to claim that their valves are now category 2 or even 1, it has been agreed that valves having characteristics as described above are out of scope. Nevertheless, as discussed in section 3.7.3, where potentially flammable atmospheres exists, users must always consider the electrostatic ignition risks.