Until recently, a manufacturer of electrical products for hazardous locations would have to design equipment to meet the national standards of each country in which he wanted to sell its products. Today, a manufacturer can go to almost any Certification Agency and receive a Certification Mark which will be accepted in almost any country in the world. However there are still differences between certifications. For instance, ATEX is a regional scheme in the European Union, and is mandatory. IECEx is a global certification, is voluntary and is open to all countries.
Equipment for use in hazardous locations must be certified to an appropriate national standard and marked as such by an accredited third party testing organization. There are currently 3 different certifications of products used in hazardous locations
North American Certification
The equivalent of the ATEX directive in the US is the HAZLOC standard. This standard given by the Occupational Safety and Health Administration defines and classifies hazardous locations such as explosive atmospheres. It aims to control the risks related to explosion in certain environments.
It comprises two elements:
– testing and evaluation of products being used
– inspection of the factory
In North America, all electrical equipment must be approved/certified as follows:
• In the USA, by a Nationally Recognized Testing Laboratory (NRTL) accredited by OSHA.
• In Canada, by a Certification Body accredited by the Standards Council of Canada (SCC).
• The proof of certification must be displayed on the equipment in the form of the mark or label of the certification body.A certificate/declaration of compliance is not sufficient.
The Certification Body that granted the certification must inspect each factory (defined as the location where the product is manufactured and labelled) four times per year. This is the same for every Certification Body, and each must perform their own inspections. This is significantly different from ATEX and IECEx, certifications where a manufacturer may have Certificates issued by a number of different Notified Bodies, but the audit is only performed by one.
In North America, hazardous locations have traditionally been defined by a combination of classes and divisions .
In the U.S. and Canada, the certification of hazardous locations electrical equipment is cnow hanging and is evolving to the zone system. There is now an international 3-Zone area classification system for equipment used in hazardous locations.
• Zone 0 – An place in which an explosive gas atmosphere is continuously present
• Zone 1 – A place in which an explosive atmosphere is likely to occur in normal operation
• Zone 2 – A place which an explosive gas atmosphere does not normally exist.
In Canada, all new installations must use the 3-Zone system. Existing installations may continue to use the 2-Division system or opt to re-classify using the 3-Zone system.
In the U.S., all installations (both new and existing) can either continue using the 2-Division system or re-classify their product using the 3-Zone system.
The ATEX directives set the minimum standards for both employer and manufacturer explosive atmospheres. It is the responsibility of the Employer to conduct an assessment of explosive risk and to take necessary measures to eliminate or reduce the risk.
If you use electrical equipment for hazardous locations in the European Union, your equipment must comply with the ATEX directive. The ATEX directive requires the following major elements to be met in order to apply the ATEX marking:
• The CE mark – The CE mark is a self-declaration marking indicating that your equipment conforms to applicable technical provisions and ATEX requirements and other directives.
• Essential health and safety requirements – Annex II of the ATEX directive, requires that you establish principles of integrated explosion safety from all electrical and non-electrical ignition sources. You can demonstrate compliance to these requirements by following the harmonized European standard series EN 60079.
• EC Type Examination Certificate – For Category 1 (electrical and mechanical) and Category 2 (electrical) equipment, a Notified Body will need to verify that your equipment has met the relevant applicable provisions of the ATEX directive in order to receive an EC Type Examination Certificate. For Category 3 equipment, an EC Type Examination Certificate is not required, however, manufacturers must ensure that your products comply with ATEX by following the appropriate conformity route.
• Quality Assessment – The facility(s) producing your equipment must undergo a Quality Assessment of EN13980 which will result in a Notified Body issuing you a Quality Assurance Notification (QAN).
The IECEx has put in place a number of conformity assessment schemes which
provide assurance that equipment and systems are manufactured and operated
according to International Standards of safety.The IECEx Scheme is designed to facilitate the international trade of electrical equipment used in explosive, hazardous environments (Ex equipment). It is not compulsory.