The Laboratory for Equipment in Hazardous Areas (LEAC) performs tests established by IEC and ABNT NBR standards applicable to parts of electrical equipment and their accessories designed for use in potentially explosive atmospheres. These standards, which include the families designated by IEC 60079 and ABNT NBR IEC 60079, refer to the application of tests to assess construction requirements and ensure conditions for the safe use of electrical equipment and accesories intended for operation in areas at risk of explosion fomred by atmosphres of flammable gases diluted in air.

In addition to general requirements for electrical equipment dsignd for use in these environments, the IEC and ABNT NBR IEC standards that comprise the current scope of the laboratory’s Cgcre accreditation include specific requirements for products designed in accordance with the following techniqus: enclosure protection against explosion, sand immersion protection, oil immersion protction, increased safety protection, intrinsic safety protection, type “n” protection and encapsulation protection.

The LEAC typically performs tests for Product Certification Agencies (OCPs) accredited by Cgcre, as well as tests to assess the performance of enclosures or metallic test specimens according to the accredited standards required by manufacturers.

In 2008, LABELO received Cgcre accreditation to perform specific tests established by the items of standards in forc at the time (NBR 9518:1997, IEC 60079-0:2000, IEC 60079-7:2001, IEC 60079-15:2001 and IEC 60079-18:1992). In 2005, with a wider scope of accredited tests though still pertaining specific items of the relevant IEC standards, th LEAC was relocated to from building 30 to building 13 of the PUCRS central campus. The move was the result of the operationalization of laboratory exnasion, including a new and significant extension of scope, fully implemented in 2008.

Through funding received from the National Scientific and Technological Development Fund – FNDCT – granted by the Financier of Studies and Projects – FINEP – following approval of the project in the Basic Industrial Technology Program (TIB), LABELO established the infrastructure needed to conduct tests with flammable gases as described by the secific standards applicable to equipment with explosion-proof enclosures and instrinsically safe equipment.

The technological support that enabled the expansion of the laboratory was achieved through training conducted by technical teams from the PTB laboratories (Physikalisch-Technische Bundesanstalt) in Braunschweig, Germany, and from UL (Underwriters Laboratories) in Northbrook, USA.

The training courses for laboratory technicians as well as the construction work necessary to expand the facilities were covered by PUCRS as part of the execution of th aforementioned project. The physical area allocated by the University to LABELO to house the current lab cover an area of 170 m2. The premises designated to assessment testing for the index of protection (IP code) provided by enclosures, establihed by IEC 60529, comprise an area of aproximately 50 m2.

The inauguration of this sace took place on November 9, 2005, in conjunction with LABELO’S complex of energy efficiency labs for household appliances, established through an agreement between PUCRS and Eletrobras in support of the National Energy Conservation Program – PROCEL. The extended scope of accredited tests for the laboratory, including approval for flammable gas tests in accordance with IEC and ABNT NBR IEC 60079-1 and 60079-11, was obtained following a technical audit by Cgcre in May 2008.

The list of the laboratory’s accredited services includes tests covered by the most recent editions of the IEC and ABNT NBR IEC series 60079, which establish general (part 0) and specific requirements for electrical equipment with protection provided by:
(a) explosion roof enclosures (part 1);
(b) sand immersion (part 5);
(c) oil immersion (part 6);
(d) increased safety (part 7);
(e) intrinsic safety (part 11);
(f) “n” protection (part 15) and
(g) encapsulation (part 18).

The current scoe of Cgcre accreditation for the LEAC can be viewed on the INMETRO website via the following link: http://www.inmetro.gov.br/laboratorios/rble/docs/CRL0075.pdf .

Areas at risk of explosion are classified according to the greater or lesser probability of the formation of an explosive atmosphere in their interior, that is, according to the degree of risk associated with them. Thus, zones are identified that exhibit continuous, occasional or rare explosive potential; these are identified, respectively, as Zone 0, Zone 1 and Zone 2.

Manufacturers of electrical equipment and components intended for use in such environments can use different construction techniques or a combination of these to adapt their products to the restrictive characteristics imposed by potentially explosive environments.

The classic construction techniques used provide different types of protection, as per the table below which shows the specific IEC and ABNT NBR IEC standards that establish the respective construction requirements and tests to be applied to such equipment.

Selecting electrical equipment and components for use in potentially explosive zones, traditionally based on their means of construction, has recently been increasingly performed using a new approach that aims to identify them according to their inherent risk of ignition. In order to make the application of this new methodology feasible, and based on the most recent editions of IEC (2007) and ABNT NBR IEC (2008) norms, the relevant standardization introduced a regime of protection levels for equipment (EPL or equipment protection levels). These are related to the ignition risk of the devices, regardless of their construction elements (that is, the type of protection involved).