HYDAC components & systems for maximum explosion protection

From ATEX to IECEx to NEC – products for potentially explosive atmospheres

The EU has issued two harmonised directives for Europe relating to health and safety.

Requirements for machinery and equipment

Directive 2014/34/EU of the European Parliament on the harmonisation of the laws of the Member States relating to equipment and protective systems intended for use in potentially explosive atmospheres. This directive governs the use of both electrical equipment and non-electrical equipment in potentially explosive atmospheres. This directive is mainly aimed at manufacturers of devices and components that are to be used in potentially explosive atmospheres. It replaced the first ATEX directive 94/9/EG. Since the 20th April 2016, all new products launched on the market must be certified in accordance with the new directive 2014/34/EU. All certificates issued under the directive 94/9/EC will remain valid, however.

Requirements that apply to the system builder/operator

Directive 99/92/EC (ATEX 153) defines the minimum requirements for health and safety in workplaces, for operating conditions and for the handling of products and materials in potentially explosive atmospheres. The directive divides up the workplace into zones and defines criteria for categorising the products inside these zones.

Transposition into national law

The directives have been transposed into national law in the countries of the European Union. In Germany, Directive 2014/34/EC was transposed with the “Eleventh Ordinance on the Product Safety Act” – also known as the Explosion Protection Product Ordinance (ExVO). Directive 99/92/EC was transposed with the German Ordinance on Industrial Safety (BetrSichV) and the German Ordinance on Hazardous Substances (GefStoffV).

The IEC publishes globally standardised standards for electrical technology and electronics. Technical committees compile the standards for the various specialist areas. To ensure harmonisation, the standards published by the IEC are predominantly adopted in national and European standards without any major changes made. IEC publications concerning the explosion protection of electrical devices and systems are compiled by the TC31 Technical Committee. As a certification scheme, IECEx creates a global framework for independent testing and certification of devices and services relating to explosion protection.
Like ATEX, IECEx divides the areas at risk into zones on the basis of the frequency and duration of the hazard.

In the USA, the National Electrical Code (NEC)applies to electrical equipment used in potentially explosive atmospheres.

Unlike the regulations in Europe and the IECEx scheme, the NEC 500-504 divides the potentially explosive atmospheres into three classes (Classes I to III for gases, dusts and fibres) and two divisions for the frequency and duration of the presence of these substances. In 1996, NEC 505–506 introduced a zone model similar to the international scheme, parallel to the class model.
Equipment that is to be used in mining is certified according to the regulations of the Mine Safety and Health Administration (MSHA).

In Canada, approval is issued in accordance with the Canadian Electrical Code (CEC 18). The classification of the areas was previously mainly based on the division model, as is the case in the USA. Since the last revision of the CEC in 2015, the zone model exclusively applies for new systems and new designs, similar to IECEx. Old equipment according to the division model can continue to be operated according to the previous regulations (Annex J18). The Canadian provinces decide on the implementation of the CEC separately. Supplements are sometimes added.

The current set of regulations is the Inmetro Directive 179/2010. This directive directly accepts certificates in compliance with the IECEx scheme, but unlike IECEx certificates they are only valid for three years. Other certificates such as ATEX are only recognised if they are harmonised with the IEC 60079 standards.

Russia formed an economic alliance, the Eurasian Customs Union (EACU), with Belarus, Kazakhstan, Armenia and Kyrgyzstan. This resulted in uniform regulations being implemented in these countries. Explosion protection is regulated in the TR-CU 012/2011 directive. EAC certificates can be issued for a one-off delivery or for 1, 3 or up to 5 years validity. ATEX or IECEx certificates are accepted as the basis for the EAC certification.

Electrical equipment in potentially explosive atmospheres needs to be approved by the PESO – Petroleum and Explosive Safety Organization. For the approval of equipment, the Indian regulations differentiate between devices manufactured in India and devices imported to India. For Indian devices, only the national standards apply, which are based in part on the older versions of the IEC or EN standards. For imported devices, IECEx or ATEX certificates in accordance with the latest standards are required. Approval can only be granted by the CCoE - Chief Controller of Explosives via an accredited Indian test laboratory. Test reports issued by non-Indian test labs are taken into account in the obligatory inspection. The Directorate General of Mines Safety (DGMS) is responsible for products used in mining.

The certification in China is similar to the IECEx scheme. It is based on IEC and EN standards that have been adopted or modified. ATEX or IECEx certifications can be used as a basis for the Chinese certification. NEPSI certificates must be renewed after five years.

In Korea, certification is also carried out in accordance with the IECEx scheme. The Korean regulations are also based on IEC and EN standards that have been either adopted without change or modified. ATEX or IECEx certificates that have already been issued can form the basis of certification, although additional national regulations must be taken into account.

In Japan, electrical equipment used in explosion protection applications must be certified by the TIIS – Technical Institution of Industrial Safety. The standards for the ignition protection types are mainly based on the standards in the IEC 60079 series. Older editions of these standards have been harmonised in some cases, however, and amendments and deviations have been included. TIIS certificates are valid for 3 years and then need to be renewed or extended. The standards only apply to devices for areas at risk of gas or dust. Group I (mining) equipment does not fall under the TIIS scheme, and also does not play a great economic role, as there is only one commercial coal mine in Japan.

Australia and New Zealand have adopted the IECEx scheme in their national regulations. This means that IECEx-certified products can be used straight away. The state of Queensland is an exception. They still have their own approvals there to some extent. The Secretariat for the IECEx system is based in Australia.