TY - CONF A1 - Bayat, Mehmet E. A1 - Huber, C. A1 - Kipphardt, Heinrich A1 - Tiebe, Carlo A1 - Engelhard, Carsten T1 - Towards a sensor-based methodology to determine online calorific values of H2-enriched natural gases in the grid N2 - The German National Hydrogen Strategy (NWS) envisions a transition towards a hydrogen-based energy grid. However, due to the material incompatibility of existing pipeline infrastructure for amounts of hydrogen higher than 10 cmol/mol, many system components of the existing grid must be replaced with significant costs and considerable time investments. Given these constraints, the admixture of hydrogen into natural gas (NG) to create a hydrogen-enriched NG blend has been designated as a transitional technology. The NWS supports this approach on a regional and time-limited basis, but clearly states that it is not intended as a permanent solution. Nevertheless, the conversion to a fully hydrogen-based grid is expected to take several decades. During this transitional phase, precise process analytical monitoring of hydrogen amounts in the NG blend is essential to ensure both energy efficiency via calorific value control and operational safety. These procedures require cost-effective, robust, and reliable sensor technologies capable of real-time, in situ/on-site quantification of hydrogen amounts in NG. In response to this need, we have advanced a physical sensing approach utilizing an oscillating cantilever in collaboration with Truedyne Sensor AG. This sensor system enables quantification of hydrogen amounts, direct calorific value determination as well as display of beneficial gas properties, like density, viscosity, and thermal conductivity. Moreover, the enhanced cantilever system enables direct physical sensing and can also be operated in a quasi-binary mode. We performed comparative evaluations against two benchmark sensor systems to validate the developed technology. One utilizes chemical sensing, and the other operates on thermal conductivity measurements for hydrogen quantification. Through standardized testing, we demonstrated that the cantilever-based sensor offers both high effectiveness and competitive performance compared to current state-of-the-art technologies for accurate hydrogen detection in natural gas and precise determination of its calorific value. T2 - Gas Analysis 2026 CY - Paris, France DA - 27.01.2026 KW - Hydrogen KW - Natural Gas KW - Sensor KW - Calorific Value KW - Grid PY - 2026 AN - OPUS4-65505 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bayat, Mehmet Emin A1 - Kipphardt, Heinrich A1 - Tiebe, Carlo A1 - Tuma, Dirk A1 - Engelhard, Carsten T1 - Trace-Level Ammonia–Water Interactions in Hydrogen: Challenges in Gas Purity Analysis Using Optical-Feedback Cavity-Enhanced Absorption Spectroscopy (OF-CEAS) N2 - Ammonia is a critical impurity in hydrogen fuel due to its irreversible poisoning effect on proton exchange membrane fuel cells. Therefore, international standards (e.g., ISO 14687) set a stringent threshold of 100 nmol/mol. Furthermore, with the growing potential use of ammonia as a hydrogen carrier, its accurate quantification is becoming increasingly important. However, the presence of trace humidity poses analytical challenges, as ammonia may interact with water or interfaces, thereby affecting its detectability. Therefore, the goal of this work is to enable accurate trace ammonia quantification for hydrogen purity measurements through fundamental studies of the methodological challenges. Here, low-pressure sampling (ultra)long-path Optical-Feedback Cavity-Enhanced Absorption Spectroscopy (OF-CEAS) was applied with an effective optical path length of approximately 6.17 km. We studied three average amounts of ammonia: (38.2 ± 0.8) nmol/mol, (74.8 ± 0.7) nmol/mol, and (112.1 ± 1.2) nmol/mol. Furthermore, these amounts were investigated at trace-humidity levels ranging from 0.8 to 8.5 ppmV. We observed a systematic, nonlinear, and humidity-dependent positive measurement bias of up to + (1.0 ± 0.2) nmol/mol at the maximum investigated trace-humidity volume fraction of 8.5 ppmV. This bias was not caused by spectral interference but rather by water-induced accumulation of ammonia within the optical cavity. Moreover, time-resolved measurements in the presence of trace ammonia showed that water desorption follows first-order kinetics, whereas water adsorption followed mixed-order kinetics with an apparent reaction order of 1.57 ± 0.03. Distinct hydration states of surface-bound ammonia were identified, whereas under dry conditions and with increasing amounts of ammonia, enhanced surface adhesion through intermolecular clustering was observed. In addition, the presence of ammonium species within the sorption layer was indirectly confirmed by our experiments. In conclusion, we provide a deeper insight into trace-level ammonia–water interactions and establish a framework for optimizing methodologies, particularly for (ultra)long-path optical gas measurement systems. KW - Ammonia KW - Hydrogen KW - OF-CEAS KW - Humidity KW - Surface Interactions KW - Adsorption PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-643627 DO - https://doi.org/10.1021/acsmeasuresciau.5c00105 SN - 2694-250X SP - 1 EP - 15 PB - American Chemical Society (ACS) AN - OPUS4-64362 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo A1 - Bayat, Mehmet E. T1 - Measurement and Testing Methods for Sensors in Hydrogen Technologies N2 - To ensure accurate results, it is advisable to conduct sensor testing under controlled conditions, focusing on identifying specific properties and quantifying performance criteria. The necessity of these evaluations lies in determining if a potentially beneficial sensor is a good fit for a specific application. Devices are typically factory-calibrated in according to ISO/IEC 17025, followed by testing/validation prior to intended use. Subsequent inspections/validations performance tests and long-term stability should be repeated in appropriate intervals. We present the testing and calibration validation of a hydrogen sensor intended for safety applications, using dynamic dilution of hydrogen into clean, dry air. • Sensor testing for the determination of non-explosive gas mixture composition, response time and characteristic curves of gas sensors, gas measuring devices. • Hydrogen mole fraction: 100 μmol/mol to > 4.0 cmol/mol – (approximately equal to 0.1 Vol-% to > 4.0 Vol-%) • Humidity: frost-point temperatures in the range of -85 °C to 15 °C (equal to 0.2 μmol/mol to 17000 μmol/mol humidity mole fraction) at ambient pressure • Sensor output provided directly in hydrogen volume percent, as defined by the factory calibration. The results obtained from the device under test demonstrate the effectiveness of the evaluated gas sensor in detecting and quantifying hydrogen. Its responses to different amounts of hydrogen in air and reliably returns to zero. To quantify the generated hydrogen mole fractions in situ and in operando, a process-GC-TCD-TCD system calibrated against our primary gas standards was used, ensuring the highest accuracy as a designated institute for primary gas standards. This procedure provides a foundation for modern and efficient quality assurance of gas sensors. T2 - 2025 IARIA Annual Congress on Frontiers in Science, Technology, Services, and Applications CY - Venice, Italy DA - 06.07.2025 KW - Hydrogen KW - Sensor KW - Quality KW - Validation KW - Data analysis KW - Reference procedure PY - 2025 AN - OPUS4-64047 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bayat, Mehmet A1 - Kipphardt, Heinrich A1 - Tiebe, Carlo A1 - Engelhard, Carsten T1 - Effect of Trace Humidity on Trace Ammonia Quantification N2 - Hydrogen is receiving growing attention as a promising medium for energy storage and transportation. Proton exchange membrane (PEM) fuel cells are a key technology for energy conversion from hydrogen. However, high purity hydrogen is required for this technology, as described in standards such as ISO 14687:2019. A critical impurity that impairs PEM efficiency is ammonia, for which a limit value of 100 nmol/mol applies. In addition, the maximum amount of humidity is specified with 5 µmol/mol. The presence of humidity in hydrogen at levels up to 50 times higher than ammonia raises the critical question of whether ammonia can still be quantified accurately in the lower nmol/mol range without interference from water. In addition, the general question arises as to whether the critical analyte, ammonia, can still be detected at all, given the expected surface effects at such amounts of trace humidity. In this work, we describe the influence of trace humidity on the surface behavior of adsorbed ammonia on stainless steel. Samples with ammonia at approximately 100 nmol/mol in hydrogen, with trace humidity levels ranging from 3 µmol/mol to 10 µmol/mol, were carefully prepared using dynamic mixing. Humidification was conducted using an advanced saturation method. These samples were investigated under atmospheric conditions using low pressure sampling Optical Feedback Cavity Enhanced Absorption Spectroscopy (OFCEAS). From the observed time-dependent signals, kinetics were determined and analyzed, yielding insights on the strength of the adsorption behavior of the analytes. T2 - ANAKON 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - OF-CEAS KW - Hydrogen KW - Ammonia KW - Water KW - Humidity KW - Kinetics KW - Adsorption PY - 2025 UR - https://veranstaltungen.gdch.de/microsite/index.cfm?l=11713&sp_id=2&selSiteID=vplanner AN - OPUS4-64046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Error prevention, damage prevention, and safety management in hydrogen technologies N2 - This tutorial presents requirements and properties of sensor systems and shows application examples of these technologies for safety and process control for hydrogen technologies. Sensor systems are widely used in hydrogen technologies. The focus is on gas sensors as well as sensors for pressure, temperature, and gas flow. These systems are applied, among other things, for monitoring and control of operating conditions, indication of hazardous conditions and triggering of alarms. To integrate the error avoidance and loss prevention strategy into hydrogen technologies. This includes the implementation of preventive measures as elements of safety management to identify and eliminate potential sources of error. In addition, training should be specifically focused on avoiding errors and the safe use of hydrogen technologies. A well-thought-out strategy for error prevention makes a significant contribution to preventing accidents and increasing overall safety when using hydrogen. T2 - Sensor and Measurement Science International (SMSI) CY - Nuremberg, Germany DA - 06.05.2025 KW - Hydrogen KW - Safety Management KW - Gas Sensors KW - Performance Testing PY - 2025 AN - OPUS4-63280 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Error Prevention, Damage Prevention, and Safety Management in Hydrogen Technologies N2 - In order to integrate the error prevention and damage prevention strategy into hydrogen technologies, it is important to proactively look out for potential weaknesses in the systems and processes. This includes the implementation of preventive measures as elements of safety management in order to identify and eliminate potential sources of error. In addition, training should be specifically focussed on avoiding errors and the safe use of hydrogen technologies. The principial approach of a gas sensor testing laboratory shows how to ensure reliable results, it is advisable to conduct sensor testing under controlled conditions, focusing on identifying specific properties and quantifying performance criteria. A well thought-out strategy for error prevention makes a significant contribution to preventing accidents and increasing overall safety when using hydrogen. T2 - 5th Germany-Korea Hydrogen Conference CY - Halle (Saale), Germany DA - 22.10.2024 KW - Hydrogen KW - Safety KW - Safety Management KW - Error Prevention KW - Reference Procedure PY - 2024 AN - OPUS4-62563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Hydrogen Sensing - Sensors for Safety and Process Control in Hydrogen Technologies N2 - The success of this energy transition and the efficient utilization of green hydrogen as a pristine energy carrier hinge upon the cultivation of hydrogen readiness, swift market expansion, and the establishment of crucial value chains within national and European contexts. Paramount to these objectives are reliable quality and safety standards, essential for ensuring supply safety, environmental compatibility, and instilling confidence in these technologies. In the realm of safety management systems, gas sensors emerge as vital components for detecting hydrogen. This presentation delves into the imperative role of hydrogen systems, emphasizing their capability to monitor and control operations, issue warnings, signal hazardous conditions, and sound alarms. It explores the intricate landscape of functional safety considerations and addresses the challenges associated with measurement uncertainty in sensor testing. A diverse array of sensors catering to hydrogen, pressure, temperature, and flow are available, each contributing significantly to the safety and efficiency of hydrogen technologies. Applications are envisaged to adhere meticulously to quality infrastructural regulations, codes, and standards, ensuring seamless integration and operation within the broader hydrogen ecosystem. This discussion underscores the ubiquitous presence of sensor systems across various fields within hydrogen technologies, illustrating their multifaceted contributions to safety, reliability, and overall success in realizing the transformative potential of green hydrogen. T2 - Joint European Summer School JESS 2024 CY - Vravrona, Greece DA - 16.09.2024 KW - H2Safety@BAM KW - Hydrogen KW - Sensor KW - Sensor technology KW - Safety KW - Process control PY - 2024 AN - OPUS4-61677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bernardy, Christopher A1 - Konert, Florian A1 - Popiela, Bartosz A1 - Sarif, Raduan T1 - H2Safety@BAM: Competence Center for safe hydrogen technologies N2 - Presentation of the competence center H2Safety@BAM at the European PhD Hydrogen Conference 2024 in Ghent, Belgium. T2 - European PhD Hydrogen Conference 2024 (EPHyC2024) CY - Ghent, Belgium DA - 20.03.2024 KW - H2safety KW - Hydrogen KW - Safety KW - Competence center PY - 2024 AN - OPUS4-59756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Hydrogen sensing - Sensors for safety and process control in Hydrogentechnologies N2 - The success of this energy transition and the efficient utilization of green hydrogen as a pristine energy carrier hinge upon the cultivation of hydrogen readiness, swift market expansion, and the establishment of crucial value chains within national and European contexts. Paramount to these objectives are reliable quality and safety standards, essential for ensuring supply safety, environmental compatibility, and instilling confidence in these technologies. In the realm of safety management systems, gas sensors emerge as vital components for detecting hydrogen. This presentation delves into the imperative role of hydrogen systems, emphasizing their capability to monitor and control operations, issue warnings, signal hazardous conditions, and sound alarms. It explores the intricate landscape of functional safety considerations and addresses the challenges associated with measurement uncertainty in sensor testing. A diverse array of sensors catering to hydrogen, pressure, temperature, and flow are available, each contributing significantly to the safety and efficiency of hydrogen technologies. Applications are envisaged to adhere meticulously to quality infrastructural regulations, codes, and standards, ensuring seamless integration and operation within the broader hydrogen ecosystem. This discussion underscores the ubiquitous presence of sensor systems across various fields within hydrogen technologies, illustrating their multifaceted contributions to safety, reliability, and overall success in realizing the transformative potential of green hydrogen. T2 - Summer School 2023 Characterization of micro- and nano-materials at BTU Cottbus CY - Cottbus, Germany DA - 11.09.2023 KW - H2Safety@BAM KW - Hydrogen KW - Sensor KW - Gas detection KW - Process control KW - Safety KW - Sensor testing PY - 2023 AN - OPUS4-59227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Hydrogen sensing - Sensors for safety and process control in Hydrogentechnologies N2 - The success of this energy transition and the efficient utilization of green hydrogen as a pristine energy carrier hinge upon the cultivation of hydrogen readiness, swift market expansion, and the establishment of crucial value chains within national and European contexts. Paramount to these objectives are reliable quality and safety standards, essential for ensuring supply safety, environmental compatibility, and instilling confidence in these technologies. In the realm of safety management systems, gas sensors emerge as vital components for detecting hydrogen. This presentation delves into the imperative role of hydrogen systems, emphasizing their capability to monitor and control operations, issue warnings, signal hazardous conditions, and sound alarms. It explores the intricate landscape of functional safety considerations and addresses the challenges associated with measurement uncertainty in sensor testing. A diverse array of sensors catering to hydrogen, pressure, temperature, and flow are available, each contributing significantly to the safety and efficiency of hydrogen technologies. Applications are envisaged to adhere meticulously to quality infrastructural regulations, codes, and standards, ensuring seamless integration and operation within the broader hydrogen ecosystem. This discussion underscores the ubiquitous presence of sensor systems across various fields within hydrogen technologies, illustrating their multifaceted contributions to safety, reliability, and overall success in realizing the transformative potential of green hydrogen. T2 - Joint European Summer School 2023 on Fuel Cell, Electrolyser, and Battery Technologies CY - Vravrona, Greece DA - 17.09.2023 KW - H2Safety@BAM KW - SensRef KW - Hydrogen KW - KICstartH2 KW - Gas detection KW - Sensor testing KW - Hydrogen gas sensor PY - 2023 AN - OPUS4-59228 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Sensors for safety and process control in hydrogen technologies N2 - This tutorial provides an overview of the utilization of sensor systems in hydrogen technologies. It discusses the necessary criteria and characteristics of sensor systems, and also demonstrates practical applications of these technologies in terms of safety and process control. Emphasis is placed on various types of sensors such as gas sensors, pressure sensors, temperature sensors, and gas flow sensors. These systems find application in monitoring and regulating operational parameters, detecting potentially dangerous situations, and activating alarm systems. T2 - Sensor and Measurement Science International - SMSI 2023 CY - Nuremberg, Germany DA - 08.05.2023 KW - H2Safety@BAM KW - SensRef KW - Hydrogen KW - Gas sensor KW - Functional safety KW - Uncertainty KW - QI-Digital PY - 2023 AN - OPUS4-57532 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Maiwald, Michael T1 - Competence Centre H2Safety@BAM – Safeguarding the Quality Infrastructure in the Hydrogen Economy N2 - Hydrogen is a central component of the energy transition and the European Green Deal for a climate-neutral Europe. To achieve the goals defined for 2050, the EU and the German government have developed a framework for action and are making long-term investments in research, development, and the rapid implementation of innovative hydrogen technologies. With the Competence Centre "H2Safety@BAM", BAM is creating the safety-related prerequisites for the successful implementation of hydrogen technologies at national as well as European level. To this end, BAM conducts research, testing and consulting in a holistic and inter-disciplinary manner under one roof – in the Competence Centre H2Safety@BAM. The activities of the competence centre focus on ensuring the safety of infra-structures, plants, and processes as well as innovative hydrogen transport and storage systems based on digital quality testing and the experimental testing of components and systems. It thus creates the prerequisites for the implementation and adaptation of legal framework conditions as well as for standardization. Closely related to this are investigations into the properties and compatibility of metallic materials and polymers as well as friction systems for the safe operation of components, plants, processes, and systems. This interdisciplinary and holistic approach is complemented by the development of gas analytics and suitable sensors, online measurements of gas properties in process control, test scenarios under real conditions as well as impact assessments of accidents and risk assessments and risk management systems derived from them. With its portfolio of tasks and competences, BAM builds trust in the safety and reliability of technical system solutions for hydrogen. T2 - 772. WE-Heraeus-Seminar - Metrology and Process Safety for Hydrogen Technologies & Applications CY - Bad Honnef, Germany DA - 10.10.2022 KW - H2Safety@BAM KW - Hydrogen KW - Competence Center KW - Hydrogen Strategy KW - Green Deal KW - Safety KW - Risk Assessment KW - Quality Infrastructure PY - 2022 UR - https://www.we-heraeus-stiftung.de/veranstaltungen/metrology-and-process-safety-for-hydrogen-technologies-and-applications/ AN - OPUS4-55986 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nattuveettil, Keerthana A1 - Brunner, Nanine A1 - Tiebe, Carlo A1 - Melzer, Michael A1 - Johann, Sergej A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias T1 - Einsatz von Sensortechnologien an einer Wasserstofftankstelle als Beitrag zur digitalen Qualitätsinfrastruktur T1 - Use of sensor technologies at hydrogen test platform as a part of QI Digital N2 - Die Optimierung und Validierung des digitalen Wasserstofftankstellenmanagements mit Sensortechnologien ist das übergeordnete Ziel des Teilprojekts Digitale Qualitätsinfrastruktur mit Sensortechnologien (QIST) am Use Case H2, im Rahmen der digitalen Qualitätsinfrastruktur (QI digital[1]). Hierfür sollen u.a. Sensornetzwerke mit digital-gestützten Auswertungsstrategien intelligent gestaltet werden (Stichwort KI bzw. digitaler Zwilling). Verschiedene, sich ergänzende Sensoren, Systemkomponenten und KI-Methoden stehen als Bausteine intelligenter Sensorsysteme zur Verfügung, mit dem Zweck, die physikalischen und chemischen Parameter an und in Anlagen umfassend und effizient zu überwachen sowie Fehlfunktionen zuverlässig zu detektieren und zu interpretieren, Abbildung 1. Konkrete Arbeitsschritte sind, nach dem Aufbau der Versuchsplattform „Wasserstofftankstelle“, die Instrumentierung von Sensorik und deren digitale Integration in das Tankstellenmanagementsystem sowie die Validierung im Realbetrieb. Die somit erzielten Messergebisse sowie die Messunsicherheiten, Historien und Verfahren werden in digitaler Form aufbereitet, gespeichert und fortlaufend in die KI-basierte Datenauswertung einbezogen, inkl. der Anbindung an die metrologische Rückführungskette. Ziele sind: • Einführung eines neuen messtechnischen Ansatzes und eines digitalen Zwillings für den Anwendungsfall "Wasserstofftankstelle" auf Basis der H2-Sensorik sowie der Zustandsgrößen Druck und Temperatur • Qualitätssicherung durch Applikationen zuverlässiger Gassensorik, Manometer und Thermometer sowie KI-Methoden zur Prozesskontrolle und Detektion von Fehlfunktionen • Nutzung von digitalen Kalibrierscheinen (DCCs) insbesondere für die Messgröße Temperatur zur Realisierung der metrologischen Rückführung in einer digitalen Qualitätsinfrastruktur T2 - Sensorik für die Digitalisierung chemischer Produktionsanlagen CY - Frankfurt a. M., Germany DA - 13.06.2022 KW - QI Digital KW - H2Safety@BAM KW - Wasserstoff KW - Hydrogen KW - Sensorik KW - Digitalisierung KW - Digitalisation PY - 2022 AN - OPUS4-55399 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kehr, Torsten T1 - Project QI-Digital - Quo vadis Use Case H2 Refueling Station? N2 - As a part of the QI-Digital cooperation project, BAM is setting up a hydrogen refuelling station research platform at the Test site for Technical Safety in Horstwalde. Based on this platform, BAM intends to develop, to test and to optimize new measurement techniques as well as data acquisition and processing methods for hydrogen refuelling stations and their periphery in close cooperation with partners from the quality infrastructure and industry. The presentation will introduce the hydrogen refuelling station use case and provide insights into the issues and research goals of the associated subprojects. T2 - H2-Colloquium of the Competence Centre „H2SAFETY@BAM” CY - Online meeting DA - 16.02.2022 KW - Hydrogen KW - Safety KW - QI-Digital PY - 2022 AN - OPUS4-54361 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tiebe, Carlo T1 - Introduction of H2Safety@BAM N2 - This contribution for the Open Forum of the 8th HSN Symposium introduces the SensRef activities of the Competence Centre H2Safety@BAM. T2 - 8. HSN-Symposium - HybridSensorNet e. V. CY - Online meeting DA - 11.11.2021 KW - H2Safety@BAM KW - SensRef KW - Hydrogen PY - 2021 AN - OPUS4-54137 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -