The issue of hand-operated valves:
Given that these will move slowly, with no possibility of forming hot surfaces (as discussed in latest ATEX guideline section § 42 on non-electrical equipment) they are not in scope of the ATEX 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 2014/34/EU 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, where potentially flammable atmospheres exist, users must always consider the electrostatic ignition risks.
What happens if you change the performance and you make it motor operated valve?
Immediately it falls to be valid under the ATEX Directive and shall be certified by the one who did the change on performance.
Keep up good work!

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