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concept to allow design, assessment and testing of electrical equipment that cannot be fully assessed within a recognized Type of Protection or combination of recognized Types of Protection because of functional or operational limitations, but which can be demonstrated to provide the necessary Equipment Protection Level [EPL].
The IEC 60079-33 applies to
• electrical equipment employing a method of protection not covered by any existing standard in the IEC 60079 series,
• electrical equipment employing one or more recognized types of protection where the design and construction is not fully compliant with the standard for the type of protection,
• electrical equipment where the intended use is outside the parameters of the scope of the standard for the type of protection.
The IEC 60079-33 is not intended for equipment that is covered by the scope of other IEC 60079 equipment standards unless
• it is clearly demonstrated that compliance with the type of protection is not feasible, and
• additional measures are applied to establish an equivalent equipment protection level.
The IEC 60079-33 for special protection “s” is applicable to Group I, Group II and Group III and for equipment protection levels Ma, Mb, Ga, Gb, Gc, Da, Db and Dc, as defined in IEC 60079-0.
So Ex s can be found in many ways.
Certificate for Ex “s” only
Where only part of the requirements for one or more recognized types of protection have been employed, the certificate shall identify the requirements for those types of protection employed and if relevant, where on the equipment they apply.
Certificate for Ex “s” with other recognized types of protection
In this case, the certificate shall identify the recognized types of protection employed and where on the equipment they apply.
Specific conditions of use
Specific conditions of use shall always be included for Ex ‘s’ equipment.
Schedule of limitations
A schedule of limitations shall always be included for Ex ‘s’ components.
Instructions
Instructions shall be prepared in accordance with the requirements of IEC 60079-0 and, in addition, a specific instruction document shall be prepared giving full details regarding
• the concept, method and unique aspects applicable to the equipment,
• installation instructions including full connection details,
• recommendations for visual, close and detailed inspection items with time frames,
• routine maintenance requirements, and
• recommendations for repair and overhaul together with the essential details necessary for the work to be carried out.
Keep up good work!
Arpad
