Inmetro Rules For All Electrical Equipments To Be Installed On Hazardous Locations

Transcription

1 Inmetro Rules For All Electrical Equipments To Be Installed On Hazardous Locations São Paulo Danillo Souza Dias Lead Auditor for Explosive Atmospheres TÜV Rheinland Brazil (this article was first featured on Ex-pert) ABSTRACT The purpose of this article is to present to the international manufacturers the Brazilian certification program known as INMETRO in order to give them the guidelines for obtaining this approval taking into account the existing types of protection under the explosive atmospheres concepts. Although there is a wide range of electrical equipments already certified on their origin countries, in Brazil it is only allowed to apply them in hazardous location after a technical evaluation in accordance with the Brazilian technical standard and Administrative Rules applicable. December 1973 it was created the National Authority for harmonizing the quality and industrial services - INMETRO - National Institute of Metrology, Quality and Technology whose the main purpose is to support the Brazilian

2 enterprises, to increase their productivity and the quality of goods and services. By considering this need, the national standards are technically and textually harmonized with the international IEC standards in a way it is possible to make the analysis with credibility and with trustable results for application on hazardous location, where the commitment with the environment, people and technology is always precisely right and respected. 1. Introduction Over the past years many efforts were dedicated for trying to reach the ideal concept that could guarantee the safety on electrical installation. Unfortunately during this several attempts many accidents have stole hundreds of lives. According to BOSSERT (2001) apud ERTHAL (2004, p. 10), many accidents haves started in electrical equipment not appropriately specified for being installed in an area where the presence of flammable substances has created special conditions for this fact. Explosive Atmospheres and hazardous locations are intrinsically connected to each other and the comprehension of these concepts becomes easier to understand and the specification of the materials and equipments to be used on the project. According to JORDAO (2002, p. 6) to elaborate a hazardous location is needed to know the behavior of the inflammable substances, mainly when they are released to the atmosphere.

3 In addition, according to BULGARELLI (2014, p 70) for an explosion to happen, an explosive atmosphere and an ignition source shall coexist. Another aspect to be considered is that related to the explosive atmospheres. In a few words, it represents the mixture with air, under atmospheric conditions, of inflammable gases, vapors or dust, where after an ignition of any substance present in the air, surely will happen an explosion. The electrical equipments itself might be considered as ignition sources once they are operating in hazardous location containing explosive atmospheres, therefore they need to be designed for reducing the risk of explosion by considering at least one of the elements of the fire triangle (heat, fuel and oxygen). According to ERTHAL (2004, p 25): The constructive measures that are applied to the electrical equipments for application in explosive atmospheres are in general based on the fire triangle. This is defined as the elements which must be present simultaneously for the occurrence of the fire, being: oxidizing element, combustible element, ignition source and the chemical reaction among them. Thus, the electrical equipments may not work as ignition source once that the other two conditions are already expected to be in the ambient. From this concept, it has been developed a wide range of constructive measures to equipments, making them safer. The main types of protection regularly found on the industry are: explosion proof Ex d, pressurized Ex p, intrinsically safe Ex i, increased safety Ex e and non incendive Ex n duly harmonized by Subcommittee SC-31 from COBEI Comitê Brasileiro de Eletricidade, Eletrônica,

4 Telecomunicações e Iluminação and later on published by ABNT Associação Brasileira de Normas Técnicas. Taking into account these standards, INMETRO through the Accredited Notified Bodies as TÜV Rheinland Brazil is, performs all technical evaluations defined on the applicable standards and also by using their administrative rule no. 179 issued on May 18th It is relevant to highlight that this procedure has began over here since 1991 by the administrative rule no. 164 (July 16th), followed by no. 238 (December, 1994), no. 121 (July, 1996), no. 84 (July, 1997), no. 103 (June, 1998), no. 176 (July, 2000), no. 174 (September, 2005), no. 83 (April, 2006), no. 179 (May, 2010) and finally the no. 89 (February, 2012) which reflects that this certification program has achieved almost twenty-four years in technical evaluations. This timeline reflect the efforts of hundreds of professionals which always are engaged in creating the best practices and solutions for ensuring the safety on electrical installations in hazardous locations. 2. INMETRO s history When one people thinks about products and services with quality assurance in Brazil, quickly comes to their mind the INMETRO marking duly applied on the product. Obviously whether the product is intended to be used in areas with an exponential risk, then automatically all legal and technical procedures must be respected and met. The quality principles determined by INMETRO and followed by all national Notified Bodies haves been introduced many decades ago. According to INMETRO (2012):

5 During the First Empire, some attempts of standardization of the Brazilian measures units has been supported in references coming from the Portuguese Court. On 1830, one year before the abdication by Dom Pedro I, the congressman Cândido Baptista de Oliveira has suggested the adoption of the decimal metric system adopted in the French Republic. However, only on 26 June 1862, on the Second Empire, Dom Pedro II has promulgated the Imperial Law no and with it formalizes, throughout the national territory, the use of the French metric system. Brazil was one of the first nations to adopt the new system as a signatory of the Metre Convention, established in May 20th, The Industrial growth in the twentieth century strengthened the need to create in Brazil more effective instruments of control that were to promote and protect manufactures and consumers. In 1961, the National Institute of Standards was created (INPM), centralizing the national metrology policy. For the full implementation of its responsibilities, he has adopted in 1962, the International System of Units (SI), consolidated by the 11th General Conference on Weights and Measures in The State Agencies, today known as Bodies Delegates receive the execution of task metrological activities, reaching every region of the country. The economic growth seen in Brazil at the end of the 1960s led to new government policies to support the productive sector. The need to keep up with the world in its technology, the improvement in accuracy and especially in meeting consumer demands, has brought new challenges for the industry. In 1973, then was born the National Institute of Metrology, Standardization and Industrial Quality, INMETRO, now called the National Institute of Metrology, Quality and Technology.

6 If a product has the INMETRO marking automatically it is accepted and approved for the intended application and the question is: how can we imagine the electrical equipments without certification? Well, this is a mandatory requirement for installation in a safe zone, however the safety instructions related into the manuals must be fulfilled by the end user. For example, if the sealing unit with INMETRO certification does not have the sealing compound during the installation, automatically the product is not longer safe. The commitment to safety must be inside us as well as it is already intrinsically within each product, technology and inserted into the environment. 3. Administrative Rule no. 179 as per of May 18th, How can I decide which model of certification is more suitable? The INMETRO rule that presents the Brazilian certification program for all Electrical Equipment for Explosive Atmospheres under Flammable Gases and Vapors and Combustible Dusts is known as Portaria INMETRO nº 179 as per of May 18th, 2010, in other words, it reflects the requirements and criteria for the compliance assessment program on electrical and electronic equipment for explosive atmospheres. It establishes three different certification processes that might help any national or international manufacturers that intend to sell its products in our country. The three models of certification are divided and separated basically by the activities to be performed, by the documentation to be checked and by the testing to be done on the products.

7 The first model, covered by the item 6.1, is classified as Model with Assessment of the Quality Management System of Product Production Process and Testing on Product and it refers to technical testing on the product and factory inspection every eighteen months. If the results were satisfactory, then the certification is granted and valid for three years. According to item 14 of the Administrative rule no. 179 issued on May 18th 2010, another possibility is to use the test reports (ExTR) issued by and accredited test laboratory (ExTL) operating within the IECEx System. The main advantage of this model is that the international manufacturers will export their products according to their needs, in other words, the quantity is unlimited. Furthermore, there is also the Model with Test Batch, covered by the item 6.2. The difference from the previous one is that on this modality it is not required follow-up audits, however the certification is only valid for the tested units which means that for each batch, a new certification process shall be carried out. On this option, the tests are defined to be performed on six percent of the batch. For both models, item 6.1 and 6.2, the tests must be performed either by a laboratory accredited by INMETRO or an ILAC member. And finally, the Special Situations Model for Imported Products also known as CSE - Certificado de Situações Especiais - which has the complete description on the item 6.3. On this case it is not required factory inspections and technical testing on laboratories.

8 According to KUSTER (2008) the principle of the certification CSE, previously named as DIPQ Declaração de Importação para Pequenas Quantidades - has started about twenty four years ago during the first discussion about this issue. It was possible because an authorization was needed for the entrance of imported and certified products on their origin countries only for those cases in that the Brazilian certification in comparison to the international market were economically unfeasible. Today this certification is applicable for twenty units per semester and the certificate is only valid for the inspected units. The current rule on item establishes the steps to be followed for reaching this certification. 4. Conclusion Under the light of the arguments described in this article, it becomes clear the need to meet the INMETRO requirements for the electrical equipments to be installed in hazardous location in Brazil. Although it has been presented under a macro view, this paper may be used as reference during the study of our national requirements. The certification processes to be applied to any related project in Brazil should be seen as an investment and not as an extra cost. The word that reflects the intention of this article is safety because it is the key of our business and work philosophy. 5. References

9 BULGARELLI, Roberval. Instalações Elétricas em Atmosferas Explosivas Problemas e Soluções. Revista Lumiere. Junho ERTHAL, Leandro. Atmosferas Potencialmente Explosivas: Um estudo de caso como contribuição para a classificação de áreas na atividade da indústria do Petróleo, Química e Petroquímica, Tese de Mestrado, Universidade Federal Fluminense, Rio de Janeiro, HISTÓRICO DO INMETRO. Acesso em 10/05/2015. JORDAO, Dacio de Miranda. Manual de instalações elétricas em indústrias químicas, petroquímicas e de petróleo. 3ª Ed. Rio de Janeiro: Qualitymark, KUSTER, Gustavo José. Acesso em 24/05/2015. PORTARIA INMETRO nº Acesso em 21/05/2015. TÜV RHEINLAND DO BRASIL. Acesso em 09/05/2015. Telefone: info@br.tuv.com