Can you buy a certified hazardous area enclosure and install your own wireless device?

Customers often ask us if they can install a standard wireless device inside a hazardous area enclosure themselves. It is a reasonable query. The short answer is no, you can’t. But the short answer does not tell the full story. There are some fundamental reasons for this, and these reasons are effectively the same for all hazardous area certification schemes around the world, including ATEX, IECEx, and North American standards under the jurisdiction of OSHA. We have written this article to explain some of these fundamental reasons in more depth. 

Device Certification 

Getting a device certified is called the type approval process, and it is just one part of the requirement. Depending on the requirement the following are applied; Annex III of the 2014/34/EU ATEX, IECEx has the requirement to follow several IECEx Operational Documents or for North America OSHA 1910 subpart A is used. Ex device design is reviewed and tested by a notified body appointed by governments to the Ex standards. These are all now typically derived from the IEC60079 series with different regions and countries having their own versions – although there are minor differences most clauses are identical to the source IECEx standard. When the product is approved it will receive and Ex Certificate stating the hazardous area classification it can be installed in as well as any safety conditions that must be applied to ensure it is safe when installed in a plant.  

Manufacturer Certification and Audits 

The other equally important part is to ensure that the manufacturer listed on the certificate ensures that the products they deliver and mark to be compliant to the certificate are identical to the type approval. With ATEX and IECEx schemes there are two choices to ensure units produced conform to the type certification. The first is where the manufacturer has every unit produced checked by a notified body, this is called unit verification and can be quite costly and is mostly used when a manufacturer doesn’t need to produce repeat batches. The more common approach is the manufacturer has audited quality system in accordance with ISO9001 and ISO80079-34 as well as holding a QAN an ATEX Quality Assurance Notification, a QAR an IECEx Quality Assessment Report and are listed as an inspected factory by an OSHA approved body for North America. These are achieved by additional quality control procedures that are audited by the Notified Bodies. For ATEX and IECEx this is done annually. For the North American certification scheme, it is a quarterly audit. 

 

Though there are several differences between the North American scheme and others, such as ATEX and IECEx, there is one main differentiator. In North America, the actual factory where the certified equipment is assembled must be audited. Whereas ATEX and IECEx mandate that the manufacturer must be audited.  

Under ATEX and IECEx, responsibility then falls to the manufacturer to ensure that factories are adhering to the type approval. It is subsequently impossible to sell an empty hazardous area enclosure and allow a third party to install the final part in the field, unless they are part of the overall manufacturing process and are audited. This applies to end users as well as systems integrators.  

This ultimately comes down to the fact that the hazardous area enclosure manufacturer retains responsibility to control compliance when audited. It is not that an Ex enclosure cannot be supplied with nothing in it, in fact, that is common practice. However, in such a case, it is classed as an Ex certified component rather than an Ex certified apparatus. The key difference is an Ex component cannot be installed by an end user whereas Ex certified apparatus can be. 

What would an end user or system integrator need to do in order to install equipment themselves?  

If we use a North American installation as an example in accordance with the relevant approvals, there would be two possible scenarios. The first scenario would require the end user to send the equipment to be installed to the original manufacturer. This would then be fitted by the manufacturer in accordance with their original certification. The second scenario would require the end user to be audited by one of the North American notified bodies. In the latter case the end user would need to have all the necessary documentation from the Ex enclosure manufacturer that states what is permissible to be installed in it to remain compliant with the apparatus type approval. This means that the manufacturer of the type approved equipment could allow a third party to install equipment in their certified enclosure provided they were part of their quality system. Ultimately, it is down to the manufacturer to control compliance to the type approval.  

With respect to schemes such as ATEX or IECEx, it is the same with the only difference being that the manufacturer would be allowed to audit the third party to ensure they were maintaining the product compliance before the device was installed on site.  

Conclusion 

In short, it is possible to buy an Ex certified enclosure as a component, but you cannot install electrical equipment in it unless you are part of the Ex equipment manufacturers quality system. In the case of North American approval, the actual Notified Body would need to audit the company doing this four times per year or inspect the equipment in batches to ensure compliance. 

Extronics iWAP range of hazardous area wireless enclosures offer a ready to go enclosure system certified to ATEX, IECEx and MET standards for Zone 1 and Zone 2 hazardous areas. The iWAP range is vendor agnostic meaning customers can choose any wireless device that can fit inside the iWAP range. Extronics will install the chosen device inside our iWAP system and ship it directly to the customer for installation. With standard configurations and custom options available, customers can be assured that the process is simple, efficient and cost effective. To learn more about our iWAP range and how easy it is to deploy your wireless device for hazardous area use, please contact our team today on +44 (0)845 277 5000 or email us at info@extronics.com.