TY - CONF A1 - Schlick-Hasper, Eva A1 - Bethke, John A1 - Vogler, Nico A1 - Goedecke, Thomas T1 - Flow properties of powdery or granular filling substances of dangerous goods packagings - Comparison of the measurement of the angle of repose and the determination of the Hausner ratio N2 - To ensure safety when transporting dangerous goods, it is important to specify the flow properties of the respective solid filling substance of the packagings. For this purpose, the angle of repose is currently used for the UN approvals in Germany. Measurements were carried out on 12 powdery or granular substances applying the angle of repose measuring methods customary in the test centres. The results of the methods differ significantly from each other. In addition, some of the techniques cannot be applied for very cohesive or coarse-grained materials. The results for the angle of repose show a strong scatter for some constellations (coefficient of variation more than 20 %). Safety during transport of dangerous goods cannot be guaranteed with this currently practiced system of measuring the angle of repose. As a consequence, an alternative parameter to characterize the flow properties of bulk materials should be used in the recognized test centers for dangerous goods packagings, such as the Hausner ratio. This approach leads to more precise test results for the substances examined (maximum coefficient of variation 2.8 %). It also has advantages in terms of applicability and occupational safety. Since the flow properties are safety-relevant, both in terms of mechanical safety and safety against the release of dangerous substances, the testing practice in the recognized test labs should be improved and standardized. T2 - IAPRI Bangkok 2022 23rd World Packaging Conference CY - Online meeting DA - 12.06.2022 KW - Sift-proofness KW - Powders KW - Flow properties KW - Flowability KW - Angle of repose KW - Hausner ratio PY - 2022 AN - OPUS4-55103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva A1 - Bruchno, Martin A1 - Goedecke, Thomas T1 - Release of Powdery or Granular Substances from Intact Dangerous Goods Bags During Road Transport - Analysis of the Causes and Development of a Test Concept N2 - The leaks of dangerous goods from actually intact bags detected in the years 2018 to 2020 tend to be at an almost constant high level. These releases of powdery or granular dangerous goods represent violations of the sift-proofness required in the dangerous goods regulations. This article first analyzes the causes. The components of the bags that are affected by leaks are micro-perforations, joins and closures, in particular internal sleeve valves. A distinction must be made between bags closed in conformity with or contrary to the manufacturer's instructions. The particle release is determined by a number of influencing factors of the filling substance, the packaging and other boundary conditions. Therefore, a comprehensive test concept is developed in this work, which takes all these factors into account. The application of this test concept facilitates the planning of the test setup and the experiments. On this basis, the complex mechanisms involved in the release of solid substances can be systematically investigated in the test laboratory. To prevent releases of powdery or granular substances from intact bags, it is necessary that the user has access to the closing instructions and the relevant properties of the test substance used for the design type approval. Further experimental investigations are needed to assess whether filling substances change their properties during transport and whether this enables them to escape. T2 - 30th IAPRI Member Conference 2021 CY - Online meeting DA - 15.06.2020 KW - Bags KW - Dangerous goods packagings KW - Sift-proofness KW - Particles KW - Leak PY - 2021 AN - OPUS4-52827 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva A1 - Eiben, Mario A1 - Drousch, Björn A1 - Heinrich, Annika A1 - Goedecke, Thomas A1 - Kraume, M. T1 - Influence of the Length of the Internal Sleeve Valve on the Release of Powdery Substances from the Closures of Valved Bags for Dangerous Goods N2 - In practice, checks on dangerous goods transports often detect leaks of powdered dangerous goods from valved bags. In this work, the influence factors of a sudden release of powdery substances from the valves of valved bags were investigated. Drop tests were carried out on paper bags of UN design type 5M2 with internal sleeve valve using two different powdery substances (Esplas H130 and zinc oxide “Rotsiegel”). The internal sleeve valves of all test samples were not sift-proof with respect to both filling substances. For almost all test samples, the Esplas H130 powder already leaked out of pasted joints during manual filling. This is a contradiction to the requirement in UN 6.1.4.18.1, according to which closures and joints of paper bags 5M2 should be sift-proof. In the drop tests, longer valve lengths had a greater sealing effect for both filling substances (for filling degrees of at least 95% and for test samples which had already been mechanically loaded). As an extreme example, at the drop height of 1.20 m and a filling degree of 100%, the released amount of zinc oxide powder from a 10 cm long valve was about 16 times higher than from a valve length of 12.5 cm. The valve length is therefore a safety-relevant parameter and should be specified by the manufacturer. To ensure that only filling goods with similar physical properties in comparison to the test substance are used for valved bags, the user must be informed of the particle size of the test substance. T2 - Abteilungskolloquium der 3. Abteilung CY - BAM-Berlin, Germany DA - 08.06.2018 KW - Dangerous goods packagings KW - Bags KW - Sacks KW - Drop-test KW - Sift-proofness PY - 2018 AN - OPUS4-45140 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva A1 - Goedecke, Thomas A1 - Kraume, M. T1 - Sift-proofness of dangerous goods packagings - An incompletely defined requirement N2 - Sift-proofness is a requirement for different types of dangerous goods packagings for solid substances according to the international Dangerous Goods Regulations. In these regulations, a siftproof packaging is defined as a packaging which is completely impermeable to dry contents. This means indirectly that absolutely no mass transport of solid substances is allowed. Moreover, this requirement applies both to the original filling substance and to fine solid material generated during transport. Further specifications, test conditions or tolerable limit values are not given. This is in contrast to physical principles and the usual practice in other fields of technology in which sift-proofness is relevant. This article shows the necessary steps for how the requirements for sift-proofness of dangerous goods packagings can be defined more precisely. Physical basics of the term “sift-proofness” are explained. A qualitative as well as a quantitative approach are possible. In any case, it is essential to carry out appropriate vibration tests to assess the sift-proofness. There is a need for systematical investigations of the sift-proofness of dangerous goods packagings. T2 - 28th IAPRI Symposium on Packaging 2017 CY - Lausanne, Switzerland DA - 09.05.2017 KW - Dangerous goods packagings KW - Sift-proofness KW - Leak proofness KW - Dust KW - Particles PY - 2017 AN - OPUS4-40284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlick-Hasper, Eva A1 - Bethke, John A1 - Goedecke, Thomas T1 - How To Measure The Angle of Repose of Hazardous Substances in the Test Centers for Dangerous Goods Packagings N2 - The flow properties of powdery or granular filling substances for dangerous goods packagings are safety-relevant parameters. To specify the flow behavior, the angle of repose is measured in the recognized test centers for dangerous goods packagings in Germany. Previous investigations performed on non-hazardous substances revealed that some of the methods currently used have disadvantages in application. Additionally, for occupational health and safety reasons, it was generally viewed critically to carry out measurements of the angle of repose for dangerous goods at all. Instead, the dimensionless Hausner ratio to describe the flow behavior was proposed. In this work, the investigations were extended to real hazardous substances to concretize the assessment. Five exemplary hazardous substances were tested for their angle of repose using the methods commonly applied in the test centers. The Hausner ratio was also determined. In addition, the influence of a different climatic preconditioning on the angle of repose measurement was examined using three selected non-hazardous bulk materials. The results show that the measurement of the angle of repose is not fundamentally excluded for dangerous goods. However, for reasons of applicability, repeatability and occupational health and safety, only the ISO method can be applied for dangerous filling substances. This method provides conservative results regarding a safety-related evaluation of flow properties for the transport of dangerous goods. In principle, both the ISO method and the determination of the Hausner ratio can be used for dangerous goods. It is also essential especially with finely powdered filling goods, to carry out controlled preconditioning. T2 - 31st IAPRI Members' Conference CY - Navi Mumbai, India DA - 22.05.2023 KW - Angle of repose KW - Flow properties KW - Flowability KW - Hausner ratio KW - Powders KW - Sift-proofness PY - 2023 AN - OPUS4-57619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -