The occupational safety and health act evaluates and explosion hazardous areas according to Korean Standard(KS C IEC 60079-10-1) and proper explosion-proof constructions with electric machines and apparatus have to be installed for flammable gases or liquids. Now, Current KS follows IEC 1st edition and there has been no change considering revisions since 2008, thus it is expected that KS will be updated based on IEC 2nd edition, revised in 2015.
In this study, IEC 60079-10-1 1st Edition is compared with IEC 2nd edition. Total 112 case studies, four chemical compounds(methane, propane, benzene, methanol)are selected, are evaluated based on IEC 1st and 2nd edition and explosion hazardous ranges of them are analyzed according to various leakage pressures and hole sizes. In order to verify the results calculated by IEC, PHAST, which is one of the most representative consequence analysis programs, is employed to calculate the explosion hazardous ranges.
As a result, it is concluded that there are many differences between IEC 1st and 2nd edition due to the discharge coeffcient and the ventilation parameters. In general, the explosion hazardous ranges evaluated by 1st edition are larger than them calculated by 2nd edition and PHAST. However, in the case of propane, the explosion hazardous ranges calculated according to the 2nd edition are larger if the leakage hole size is larger than 2.5㎟ and a leakage pressure is bigger than 0.1MPa.
Therefore, it is worth to note that the large value between the explosion hazardous ranges value calculated by the IEC technical standard(IEC 60079-10-1) 1st Edition and 2nd Edition should be selected until KS is revised in future. Also, future studies for IEC 2nd should be performed to evaluate the accuracy.