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9. 1st international round robin test on safety characteristics of hybrid mixtures

Author

Spitzer, Stefan H., Askar, Enis, Benke, Alexander, Cloney, Chris, D’Hyon, Sebastian, Dufaud, Olivier, Dyduch, Zdzislaw, Gabel, Dieter, Geoerg, Paul, Heilmann, Vanessa, Jankuj, Vojtech, Jian, Wang, Krause, Ulrich, Krietsch, Arne, Mynarz, Miroslav, Norman, Frederik, Skrinsky, Jan, Taveau, Jerome, Vignes, Alexis, Zakel, Sabine, and Zhong, Shengjun

Published
2023
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14. Impact of atrial fibrillation on 1-year outcome in patients with implantable cardioverter defibrillator or cardiac resynchronization therapy with defibrillator: results from the German DEVICE Registry

Author

Feickert, Sebastian, primary, Ewertsen, Niels Christian, additional, Köbe, Julia, additional, Kleemann, Thomas, additional, Jehle, Joachim, additional, Senges, Jochen, additional, Hochadel, Matthias, additional, Andresen, Dietrich, additional, Stellbrink, Christoph, additional, Eckardt, Lars, additional, Spitzer, Stefan, additional, Brachmann, Johannes, additional, Ince, Hüseyin, additional, and D’Ancona, Giuseppe, additional

Published
2024
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20. Study of the Safety Characteristics of Different Types of Pepper Powder (Capsicum L.).

Author

Kosár, László, Szabová, Zuzana, Kuracina, Richard, Spitzer, Stefan H., Mynarz, Miroslav, and Filipi, Bohdan

Subjects
DUST explosions, CHEMICAL properties, PEPPERS, DUST, EXPLOSIONS, POWDERS, IGNITION temperature
Abstract

This research was aimed at comparing the fire characteristics of different types of pepper in the context of explosion prevention. The following characteristics were studied: explosion pressure Pmax and Kst at selected concentrations, ignition temperature of the deposited dust layer from the hot surface, and minimum ignition energy. The comparison of the chemical properties of the used types of pepper was performed using TG/DSC. The results of the measurements suggest that different types of peppers exhibit different explosion characteristics. Each sample reached the maximum value of the explosion pressure and rate of pressure rise at different concentrations. The volume of the explosion chamber used also influenced the explosion characteristics. It is a consequence of the fact that the explosion characteristics strongly depend on the mechanism of action of a particular igniter. The minimum effect on the safety characteristics was observed when measuring the minimum ignition energy and the minimum ignition temperature of the dust layer from the hot surface. The results of the measurements suggest that different types of peppers exhibit different explosion characteristics. This information should then be considered in explosion prevention. [ABSTRACT FROM AUTHOR]

Published
2024
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27. Safety of pulsed field ablation in more than 17,000 patients with atrial fibrillation in the MANIFEST-17K study

Author

Ekanem, Emmanuel, Neuzil, Petr, Reichlin, Tobias, Kautzner, Joseph, van der Voort, Pepijn, Jais, Pierre, Chierchia, Gian-Battista, Bulava, Alan, Blaauw, Yuri, Skala, Tomas, Fiala, Martin, Duytschaever, Mattias, Szeplaki, Gabor, Schmidt, Boris, Massoullie, Grégoire, Neven, Kars, Thomas, Olivier, Vijgen, Johan, Gandjbakhch, Estelle, Scherr, Daniel, Johannessen, Arne, Keane, David, Boveda, Serge, Maury, Philippe, García-Bolao, Ignacio, Anic, Ante, Hansen, Peter Steen, Raczka, Franck, Lepillier, Antoine, Guyomar, Yves, Gupta, Dhiraj, Van Opstal, Jurren, Defaye, Pascal, Sticherling, Christian, Sommer, Philipp, Kucera, Pavel, Osca, Joaquin, Tabrizi, Fariborz, Roux, Antoine, Gramlich, Michael, Bianchi, Stefano, Adragão, Pedro, Solimene, Francesco, Tondo, Claudio, Russo, Antonio Dello, Schreieck, Jürgen, Luik, Armin, Rana, Obaida, Frommeyer, Gerrit, Anselme, Frédéric, Kreis, Ingo, Rosso, Raphael, Metzner, Andreas, Geller, Laszlo, Baldinger, Samuel H., Ferrero, Angel, Willems, Stephan, Goette, Andreas, Mellor, Greg, Mathew, Shibu, Szumowski, Lukasz, Tilz, Roland, Iacopino, Saverio, Jacobsen, Peter Karl, George, Andrikopoulos, Osmancik, Pavel, Spitzer, Stefan, Balasubramaniam, Richard, Parwani, Abdul Shokor, Deneke, Thomas, Glowniak, Andrzej, Rossillo, Antonio, Pürerfellner, Helmut, Duncker, David, Reil, Peter, Arentz, Thomas, Steven, Daniel, Olalla, Juan José, de Jong, Jonas S. S. G., Wakili, Reza, Abbey, Selim, Timo, Gottschling, Asso, Antonio, Wong, Tom, Pierre, Bertrand, Ewertsen, Niels Christian, Bergau, Leonard, Lozano-Granero, Cristina, Rivero, Maximo, Breitenstein, Alexander, Inkovaara, Jaakko, Fareh, Samir, Latcu, Decebal Gabriel, Linz, Dominik, Müller, Patrick, Ramos-Maqueda, Javier, Beiert, Thomas, Themistoclakis, Sakis, Meininghaus, Dirk Grosse, Stix, Günter, Tzeis, Stylianos, Baran, Jakub, Almroth, Henrik, Munoz, Daniel Rodriguez, de Sousa, João, Efremidis, Michalis, Balsam, Pawel, Petru, Jan, Küffer, Thomas, Peichl, Petr, Dekker, Lukas, Della Rocca, Domenico G., Moravec, Ondrej, Funasako, Moritoshi, Knecht, Sebastien, Jauvert, Gael, Chun, Julian, Eschalier, Romain, Füting, Anna, Zhao, Alexandre, Koopman, Pieter, Laredo, Mikael, Manninger, Martin, Hansen, Jim, O’Hare, Daniel, Rollin, Anne, Jurisic, Zrinka, Fink, Thomas, Chaumont, Corentin, Rillig, Andreas, Gunawerdene, Melanie, Martin, Claire, Kirstein, Bettina, Nentwich, Karin, Lehrmann, Heiko, Sultan, Arian, Bohnen, Jan, Turagam, Mohit K., and Reddy, Vivek Y.

Abstract

Pulsed field ablation (PFA) is an emerging technology for the treatment of atrial fibrillation (AF), for which pre-clinical and early-stage clinical data are suggestive of some degree of preferentiality to myocardial tissue ablation without damage to adjacent structures. Here in the MANIFEST-17K study we assessed the safety of PFA by studying the post-approval use of this treatment modality. Of the 116 centers performing post-approval PFA with a pentaspline catheter, data were received from 106 centers (91.4% participation) regarding 17,642 patients undergoing PFA (mean age 64, 34.7% female, 57.8% paroxysmal AF and 35.2% persistent AF). No esophageal complications, pulmonary vein stenosis or persistent phrenic palsy was reported (transient palsy was reported in 0.06% of patients; 11 of 17,642). Major complications, reported for ~1% of patients (173 of 17,642), were pericardial tamponade (0.36%; 63 of 17,642) and vascular events (0.30%; 53 of 17,642). Stroke was rare (0.12%; 22 of 17,642) and death was even rarer (0.03%; 5 of 17,642). Unexpected complications of PFA were coronary arterial spasm in 0.14% of patients (25 of 17,642) and hemolysis-related acute renal failure necessitating hemodialysis in 0.03% of patients (5 of 17,642). Taken together, these data indicate that PFA demonstrates a favorable safety profile by avoiding much of the collateral damage seen with conventional thermal ablation. PFA has the potential to be transformative for the management of patients with AF.

Published
2024
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32. AB-453070-2 : A RANDOMIZED CONTROLLED TRIAL OF ELECTROGRAPHIC FLOW-GUIDED ABLATION IN REDO PATIENTS WITH NON-PAROXYSMAL ATRIAL FIBRILLATION

Author

Reddy, Vivek Y., primary, Neuzil, Petr, additional, Langbein, Anke, additional, Petru, Jan, additional, Funasako, Moritoshi, additional, Dinshaw, Leon, additional, Wijchers, Sip, additional, Bhagwandien, Rohit, additional, Rillig, Andreas, additional, Spitzer, Stefan G., additional, Metzner, Andreas, additional, Kong, Melissa H., additional, and Szili-Torok, Tamas, additional

Published
2023
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33. PO-01-195 PHENOTYPING PERSISTENT AF WITH ELECTROGRAPHIC FLOW MAPPING

Author

Reddy, Vivek Y., primary, Castellano, Steven, additional, Szili-Torok, Tamas, additional, Petru, Jan, additional, Funasako, Moritoshi, additional, Hoogendijk, Mark, additional, Wijchers, Sip, additional, Spitzer, Stefan G., additional, Rillig, Andreas, additional, Neuzil, Petr, additional, and Kong, Melissa H., additional

Published
2023
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34. Influence of pre-ignition pressure rise on safety characteristics of dusts and hybrid mixtures

Author

Spitzer, Stefan H, Askar, Enis, Benke, Alexander, Janovský, Břetislav, Krause, Ulrich, Krietsch, Arne, Spitzer, Stefan H, Askar, Enis, Benke, Alexander, Janovský, Břetislav, Krause, Ulrich, and Krietsch, Arne

Abstract

For the determination of the safety characteristics of dusts it is necessary to disperse the dust in the oxidating atmosphere (usually air). In the standard procedures for dusts this is realized by a partially evacuated explosion vessel (20L-sphere) in which the dust gets injected from a dust chamber pressurized with air. Shortly after that injection (60 ms) the dust cloud gets ignited under turbulent conditions, that are otherwise seen as almost ambient with 20 degrees C and about 1 bar (abs). While there has been a lot of research about the influence of the ignition delay time and the level of turbulence in the recent years little attention was paid to the pre-ignition pressure rise and the allowed variations in the standards. In the following work we showed that the allowed ranges for the pressures in the different dust standards influence the safety characteristics of dust alone severely. Even though hybrid mixtures are an emerging risk problem in an interconnected industry there is no standard for the determination of their safety characteristics. In this work it is shown that especially for the preparation of hybrid mixtures of flammable dust and gas the pressures after injection of the dust and the mixing procedure have a large influence on the composition of the tested mixtures and therefore on the safety characteristics. Considering both effects, wrong concentration of gas and wrong initial pressure, the discrepancy of safety characteristics from different facilities will be too big to applicable. The methods to overcome these weaknesses are also presented., Pro určení bezpečnostních charakteristik prachů je nezbytné rozprášit prach v oxidační atmosféře (obvykle vzduchu). Ve standardní proceduře pro prach je toto realizováno částečně evakuovanou výbuchovou nádobou (20L-koule), ve které je prach rozprášen z prachové komory natlakované vzduchem. Krátce po tomto rozvíření (60 ms) je oblak prachu iniciován za turbulentních podmínek, které jsou jinak považovány za téměř okolní s teplotou 20 °C a okolo 1 bar (abs). Zatímco bylo v současné době věnováno hodně pozornosti věnováno době zpoždění iniciace a stupni turbulence, jen málo pozornosti bylo věnováno před-iniciačnímu nárůstu tlaku a odchylkám povoleným normou. V následující práci je ukázáno, že povolené rozsahy tlaku v různých standardech ovlivňují bezpečnostní charakteristiky samotných prachů závažně. Přestože jsou hybridní směsi rizikem v propojeném průmyslu, neexistuje norma pro určení jejich bezpečnostních charakteristik. V této práci je ukázáno, že speciálně pro přípravu hybridních směsí hořlavého prachu a plynu má tlak po rozvíření prachu a proces mísení velký vliv na složení testované směsi a proto na bezpečnostní charakteristiky. Za předpokladu obou efektů, špatné koncentrace plynu a špatného počátečního tlaku, budou rozdíly v bezpečnostních charakteristikách z různých zařízení příliš velké pro aplikaci. Metody pro překonání těchto slabin jsou také uvedeny.

Published
2023

35. 1st international round robin test on safety characteristics of hybrid mixtures

Author

Spitzer, Stefan H. (author), Askar, Enis (author), Benke, Alexander (author), Cloney, Chris (author), D'Hyon, Sebastian (author), Dufaud, Olivier (author), Dyduch, Zdzislaw (author), Gabel, Dieter (author), Taveau, J.R. (author), Spitzer, Stefan H. (author), Askar, Enis (author), Benke, Alexander (author), Cloney, Chris (author), D'Hyon, Sebastian (author), Dufaud, Olivier (author), Dyduch, Zdzislaw (author), Gabel, Dieter (author), and Taveau, J.R. (author)

Abstract

There is no applicable existing standard for the determination of safety characteristics for hybrid mixtures. While developing a new standard in a joint research project in Germany first results from parameter studies led to a standard procedure that can be adopted by laboratories that are already testing dusts in the so called 20L-sphere with as little additional effort as necessary. In fact, one of the main objectives of this research project was to keep modifications and adjustments from the generally accepted dust testing procedures as easy and minimal as possible so as to limit potential deviations from one laboratory to another. In this first round robin test on hybrid mixtures ever, with methane as gas component and a specific corn starch as dust sample, the practicality of the whole procedure, the scattering of the results and the deviation between the testing apparatuses is investigated. This paper summarizes the experimental procedure adopted and objectives of the first round-robin phase involving three of the four original German companies, plus volunteering laboratories from Australia, Belgium, Czech Republic, France, Poland and P.R. China. The results will have an impact on the new standard and may lead to robust data for later simulation purposes., Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Fluid Mechanics

Published
2023
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36. Electrographic flow–guided ablation in redo patients with persistent atrial fibrillation (FLOW-AF):design and rationale

Author

Szili-Torok, Tamas, Neuzil, Petr, Langbein, Anke, Petru, Jan, Funasako, Moritoshi, Dinshaw, Leon, Wijchers, Sip, Bhagwandien, Rohit, Rillig, Andreas, Spitzer, Stefan G., Metzner, Andreas, Kong, Melissa H., Reddy, Vivek Y., Szili-Torok, Tamas, Neuzil, Petr, Langbein, Anke, Petru, Jan, Funasako, Moritoshi, Dinshaw, Leon, Wijchers, Sip, Bhagwandien, Rohit, Rillig, Andreas, Spitzer, Stefan G., Metzner, Andreas, Kong, Melissa H., and Reddy, Vivek Y.

Abstract

Background: Electrographic flow (EGF) mapping enables the dynamic detection of functional or active atrial fibrillation (AF) sources outside the pulmonary veins (PVs), and the presence or absence of these sources offers a novel framework for classifying and treating persistent AF patients based on the underlying pathophysiology of their AF disease. Objective: The primary objective of the FLOW-AF trial is to evaluate the reliability of the EGF algorithm technology (Ablamap software) to identify AF sources and guide ablation therapy in patients with persistent AF. Methods: The FLOW-AF trial (NCT04473963) is a prospective, multicenter, randomized clinical study in which patients with persistent or long-standing persistent AF who have failed prior PV isolation (PVI) undergo EGF mapping after confirmation of intact PVI. In total, 85 patients will be enrolled and stratified based on the presence or absence of EGF-identified sources. Patients with an EGF-identified source above the predetermined activity threshold of ≥26.5% will be randomized in a 1:1 fashion to PVI only vs PVI + ablation of EGF-identified extra-PV sources of AF. Results: The primary safety endpoint is freedom from serious adverse events related to the procedure through 7 days following the randomization procedure; and the primary effectiveness endpoint is the successful elimination of significant sources of excitation with the target parameter the activity of the leading source. Conclusions: The FLOW-AF trial is a randomized study designed to evaluate the ability of the EGF mapping algorithm to identify patients with active extra-PV AF sources.

Published
2023

38. Experimental Parameter Study and Inherent Scattering of Safety Characteristics of Dusts.

Author

Spitzer, Stefan H., Krietsch, Arne, and Jankuj, Vojtech

Subjects
DUST explosions, FLAMMABLE materials, DUST & the environment, IGNITION temperature
Abstract

Safety characteristics are widely used in industrial processes to avoid explosive atmospheres (primary explosion protection) or to mitigate the consequences of an explosion (constructive explosion protection). Several laboratory parameters influence the determined values when performing the test series such as the beginning pressure and the pre-ignition pressure rise, the ignition source, the ignition energy, the burning duration and volume or the concentration of the combustible substance. In the different standards for the determination of safety characteristics of dusts there is no statement about the scattering or the deviation when parameters are chosen or occur on the borders of their allowed range. Thus, two laboratories might determine values that are hardly comparable for the same given substance. This article summarizes some of the influential factors that cause a deviation and shows the inherent scattering of dust tests when all other parameters are kept constant. It also provides some advice how to minimize the deviation and the scattering with little effort. [ABSTRACT FROM AUTHOR]

Published
2023
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39. A New Ignition Source for the Determination of Safety Characteristics of Gases.

Author

Spitzer, Stefan H., Riesner, Gerald, Zakel, Sabine, and Schierding, Carola

Subjects
FLAMMABLE gases, ELECTRONIC transformers, DUST, STANDARDS, CALORIMETRY
Abstract

Safety characteristics are used to keep processes, including flammable gases, vapors, and combustible dusts, safe. In the standards for the determination of safety characteristics of gases and vapors, the induction spark is commonly used. However, classic transformers are hard to obtain, and replacement with new electronic transformers is not explicitly allowed in the standards. This article presents the investigation of five gases that are normally used to calibrate devices for the determination of safety characteristics, the maximum experimental safe gap (MESG), with an electronic transformer, and the values are compared to the ones that are obtained with the standard transformer. Additionally, calorimetric measurements on the net energy of both ignition sources were performed as well as open-circuit voltage measurements. It is concluded that the classic type of transformer can be replaced by the new type obtaining the same results for the MESG and introducing the same amount of energy into the system. [ABSTRACT FROM AUTHOR]

Published
2023
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40. 14th International Symposium on Hazards, Prevention and Mitigation of Industrial Explosions, Proceedings

Author

Adamus, Wojciech, Addo, Albert, Alvarez-Rodriguez, Alberto, Amez, Isabel, Amyotte, Paul, Arnhold, Thorsten, Arntzen, Bjørn, Askar, Enis, Barbu, Bogdan, Barozzi, Marco, Bauwens, Regis, Bendada, Samah, Benke, Alexander, Berger, Frank, Berghmans, Jan, Bernard, Stephane, Beyer, Michael, Boeck, Lorenz, Brunzendorf, Jens, Bu, Yajie, Buchner, Christoph, Castells, Blanca, Chang, Pojul, Chen, Tengfei, Chunmiao, Yuan, Cloney, Chris, Conzen, Jens, Copelli, Sabrina, Danzi, Enrico, Dastidar, Ashok, Daubech, Jérôme, Degrève, Jan, Derudi, Marco, D'Hyon, Sebastian, Di Benedetto, Almerinda, Dobashi, Ritsu, Dorofeev, Sergey, Dueñas Santana, Julio Ariel, Dufaud, Olivier, Dufour, Anthony, Dworschak, Rene, Dyduch, Zdzisław, Dymke, Jessica, Dyrba, Patrick, Eckart, Sven, Egan, Simon, El Gadha, Chayma, El-Zahlanieh, Stephanie, Endo, Takuma, Engelmann, Frank, Essmann, Stefan, Franchini, Fausto, Franke, Steffen, Gabel, Dieter, Gambaruto, Alberto, Garcia-Torrent, Javier, Geoerg, Paul, Gerlach, Johanna, Glaude, Pierre-Alexandre, Glor, Martin, González Gómez, Orelvis, Grosshans, Holger, Guo, Yongzheng, Habib, Abdel Karim, Hébrard, Jérôme, Hecht, Kristin, Heer, Christian, Heilmann, Vanessa, Herbst, Sabrina, Hesener, Ute, Hilbert, Michael, Hisken, Helene, Huang, Chen, Huang, Weixing, Jankůj, Vojtěch, Jantac, Simon, Jean, Amelie, Johzaki, Tomoyuki, Kanbur, Harun, Kapahi, Anil Kapahi, Khan, Faisal, Kim, Wookyung, Kim, Yangkyun, Kleinert, Jan, Kluge, Martin, Koch, Florian, Kraft, Stefan, Krause, Harmut, Krause, Tim, Krause, Ulrich, Krietsch, Arne, Lakshmipathy, Sunil, Lecocq, Guillaume, León, David, Leprette, Emmanuel, Lindner-Silwester, Tino, Lucas, Melodía, Maas, Ulrich, Manchikatla, Manideep, Mao, Gongping, Mao, Huan, Markus, Detlev, Marmo, Luca, Martin, Conor, McCarthy-Singh, Bisham, Medic, Ljiljana, Meistes, Jörg, Mejía-Botero, Cristian, Melguizo-Gavilanes, Josué, Meyer, Georg, Mitu, Maria, Mogi, Toshio, Mynarz, Miroslav, Norman, Frederik, Orozco, Jesus Luis, Padron Herrera, Victor Hugo, Pan, Yangyue, Pietraccini, Matteo, Pirker, Stefan, Portarapillo, Maria, Proust, Christophe, Puttinger, Stefan, Raupenstrauch, Harald, Ren, Kaiyue, Salzano, Ernesto, Sanchirico, Roberto, Schießl, Robert, Schneiderbauer, Simon, Schüler, Niklas, Scotton, Martina Silvia, Shepherd, Joseph, Shu, Bo, Siegle, Leo, Skjold, Trygve, Skrinsky, Jan, Spijker, Christoph, Spitzer, Stefan, Springer, Niels, Stolpe, Frank, Stolz, Thomas, Tanaka, Keita, Taveau, Jerome, Thurnherr, Peter, Toman, Adrian, Trofa, Marco, Uber, Carsten, Ueda, Akihiro, Uhrland, Dirk, Valera-Medina, Agustin, Van Caneghem, Jo, van Wingerden, Kees, Vanierschot, Maarten, Veiga-López, Fernando, Verplaetsen, Filip, Vignes, Alexis, Walch, Otto, Wandt, Joachim, Wang, Jian, Wei, Aizhu, William Louis, Mame, Wu, Dejian, Xu, Wenchao, Xu, Zhijian, Yu, Chunkan, Zakel, Sabine, Zhao, Peng, and Zhong, Shengjun

Subjects
Explosion Protection, Explosions, Process Safety, Industrial Loss Prevention, Gas Dynamics
Abstract

It is our pleasure to present the proceedings of the 14th International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions (ISHPMIE). Despite the ongoing global challenges, we are happy to compile proceedings consisting of 60 high-quality papers that reflect the scientific state-of-the-art in the following topical categories: Advances in explosion protection: Strategies, measures, and protective equipment; Explosion modelling and simulation; Explosion testing; Hydrogen safety; Explosion prevention; Dust explosions; Explosion-protected devices; Hybrid mixture explosions; Flame propagation and acceleration; Ignition phenomena. All articles in this volume have been subject to a peer-review process administered by the Proceeding Editors. We are thankful to the 70 expert referees who guaranteed the professional and scientific standards expected of ISHPMIE.

Published
2023
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