PD CLC/TR 60079-33:2015

What is PD CLC/TR 60079-33‒ Equipment protection by special protection 's' about?  

PD CLC/TR 60079-33 is a part of an international multi-series standard that focuses on safety aspects for explosive atmospheres.  

PD CLC/TR 60079-33 gives the specific methodology for the assessment and testing, and requirements for marking of electrical equipment, parts of electrical equipment, and Ex components with special protection “s”. 

PD CLC/TR 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 

PD CLC/TR 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. It supplements and modifies the general requirements of IEC 60079-0.  

Note 1: PD CLC/TR 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. 

Note 2: Certain specific guidance for assessment and testing are provided in the annexes to PD CLC/TR 60079-33. 

Who is PD CLC/TR 60079-33‒ Equipment protection by special protection 's' for?  

PD CLC/TR 60079-33 on Equipment protection by special protection 's' is useful for: 

• Safety certification providing entities for electrical equipment to be used in an explosive atmosphere  
• Suppliers and dealers of electrical equipment with a type of protection “s” 
• Designers of electrical equipment in an explosive atmosphere 
• Manufacturers of safety equipment in an explosive atmosphere 
• Regulatory authorities 

Why should you use PD CLC/TR 60079-33‒ Equipment protection by special protection 's'?  

The areas where dangerous concentrations and quantities of flammable gases, vapours, or dust may be present in the atmosphere, are referred to as an explosive atmosphere. Protective measures are needed to be applied to the electrical equipment installed in such areas.  

PD CLC/TR 60079-33 serves the purpose of providing the requirements for special protection “s” for any equipment protection level (EPL), which allows the users to design, assess, and test the protection equipment or parts of equipment. It helps the users to assess the performance of the protection equipment that generally cannot be examined completely, within a recognized type of protection or combination of recognized types of protection, as the functional or operational limitations might cause an obstacle. Thus, it helps users to acquire the desired level of equipment protection in order to ensure the safety and reliability of the products. 

PD CLC/TR 60079-33 is intended to provide a framework to demonstrate how essential safety requirements can be met if not covered by established standards, thus allowing for innovation, and dealing with the unknowns.