TY - JOUR A1 - Molnarne, Maria A1 - Mizsey, P. A1 - Schröder, Volkmar T1 - Flammability of gas mixtures - Part 2: Influence of inert gases JF - Journal of hazardous materials N2 - Ternary systems, which contain flammable gas, inert gas and air, were studied in order to give the user an evaluation of the ISO 10156 calculation method for the flammability of gas mixtures. While in Part 1 of this article the fire potential of flammable gases was the focal point, the influence of inert gases on the flammability of gas mixtures was studied in Part 2. The inerting capacity of an inert gas is expressed by the dimensionless K value, the so-called “coefficient of nitrogen equivalency”. The experimental determination of K values is demonstrated by using explosion diagrams. The objective of this study was to compare the estimated results, given by ISO 10156, with measurements of explosion ranges based on the German standard DIN 51649-1, given by CERN and CHEMSAFE. The comparison shows that ISO 10156, Table 1, supplies conservative K values, which can be regarded as safe in all cases. Nevertheless, in a number of cases ISO underestimates the inerting capacity, so that non-flammable gas mixtures are considered flammable. KW - Gas classification KW - Flammability KW - Explosion limits KW - Inerting KW - Calculation method PY - 2005 DO - https://doi.org/10.1016/j.jhazmat.2005.01.033 SN - 0304-3894 VL - 121 IS - 1-3 SP - 45 EP - 49 PB - Elsevier CY - Amsterdam AN - OPUS4-7448 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Molnarne, Maria A1 - Schröder, Volkmar T1 - Comparison of calculated data for the flammability and the oxidation potential according to ISO 10156 with experimentally determined values JF - Journal of loss prevention in the process industries N2 - The classification of flammable gas mixtures is based on either testing or calculation methods proposed by the revised international standard ISO 10156. This standard is used for classification of physical hazards in Chapters 2.2 and 2.4 of the UN Globally Harmonized System of Classification and Labelling of Chemicals (GHS) and in the UN Recommendations on Transport of Dangerous Goods (TDG). The test methods of flammability and oxidizing potential in this standard were developed by BAM. Earlier versions of this standard are not based on triangular diagrams and on the reference combustible substance 'ethane'. The old material characteristics, especially in case of oxidizing potential, are based mostly on practical experience without any quantifiable test results. First time it is possible to compare experimental results from the CHEMSAFE database with the newly developed calculation method. In this paper the basic principles of the calculation methods are presented and the methods are validated by examples. A comparison of experimental flammability data with classification results gained by the calculation methods of ISO 10156 is demonstrated. KW - Gas classification KW - GHS KW - Flammability limit KW - Oxidizing potential KW - Calculation method PY - 2011 DO - https://doi.org/10.1016/j.jlp.2011.06.024 SN - 0950-4230 SN - 1873-3352 VL - 24 IS - 6 SP - 900 EP - 907 PB - Elsevier Ltd. AN - OPUS4-24176 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schröder, Volkmar A1 - Molnarne, Maria T1 - Flammability of gas mixtures - Part 1: Fire potential JF - Journal of hazardous materials N2 - International and European dangerous substances and dangerous goods regulations refer to the standard ISO 10156 (1996). This standard includes a test method and a calculation procedure for the determination of the flammability of gases and gas mixtures in air. The substance indices for the calculation, the so called “Tci values”, which characterise the fire potential, are provided as well. These ISO Tci values are derived from explosion diagrams of older literature sources which do not take into account the test method and the test apparatus. However, since the explosion limits are influenced by apparatus parameters, the Tci values and lower explosion limits, given by the ISO tables, are inconsistent with those measured according to the test method of the same standard. In consequence, applying the ISO Tci values can result in wrong classifications. In this paper internationally accepted explosion limit test methods were evaluated and Tci values were derived from explosion diagrams. Therefore, an “open vessel” method with flame propagation criterion was favoured. These values were compared with the Tci values listed in ISO 10156. In most cases, significant deviations were found. A detailed study about the influence of inert gases on flammability is the objective of Part 2. KW - Gas classification KW - Flammability KW - Explosion limit KW - Test method KW - Calculation method PY - 2005 DO - https://doi.org/10.1016/j.jhazmat.2005.01.032 SN - 0304-3894 VL - 121 IS - 1-3 SP - 37 EP - 44 PB - Elsevier CY - Amsterdam AN - OPUS4-7447 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -