TY - CONF A1 - Grimmer, Christoph A1 - Richter, Matthias A1 - Musyanovych, Anna A1 - Strzelczyk, Rebecca A1 - Horn, Wolfgang T1 - Preparation of novel emission reference materials: μ-capsules & impregnated porous materials N2 - Volatile organic compounds (VOCs) emitted by furniture and building materials can cause health issues. For an improvement of indoor air quality low emitting materials should be used. Quality assurance and –control (QA/QC) measures require an emission reference material (ERM) with a predictable emission rate of VOCs. The idea is to use porous materials as ERM, which store the VOCs inside their pores and emit them constantly. T2 - WORKSHOP: METROLOGY FOR INDOOR AIR QUALITY CY - Mol, Belgium DA - 18.10.2023 KW - Emission reference materials KW - Indoor air quality KW - Materials emissions test KW - VOC PY - 2023 AN - OPUS4-59961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Tang, Chi-Long A1 - Seeger, Stefan A1 - Röllig, Mathias T1 - Minimizing the FFF-3D printer hardware bias on particle emission by adjustment of the set extruder temperature N2 - Fused filament fabrication (FFF) on desktop 3D printers is a material extrusion-based technique often used by educational institutions, small enterprises and private households. Polymeric filaments are melted and extruded through a heated nozzle to form a 3D object in layers. The extrusion temperature is therefore a key parameter for a successful print job, but also one of the main driving factors for the emission of harmful air pollutants, namely ultrafine particles and volatile organic gases, which are formed by thermal stress on the polymeric feedstock. The awareness of potential health risks has increased the number of emission studies in the past years. However, the multiplicity of study designs makes an objective comparison of emission data challenging because printer hardware factors such as the actual extruder temperature (TE) and also feedstockspecific emissions are not considered. We assume that across the market of commercial low- and mid-price FFF printers substantial deviations between actual and set extruder temperatures exist, which have a strong effect on the emissions and hence may bias the findings of exposure studies. In our last publication, we presented a standardized feedstock-specific emission test method and showed that for each investigated feedstock an increase in actual extruder temperature was accompanied by an increase in particle emissions (Tang and Seeger, 2022). Therefore, any systematic discrepancy between set and actual extruder temperature matters. In this study, we used a thermocouple and an infrared camera to measure the actual extruder temperatures at different heights. We found significant under- and overestimation of the actual extruder temperatures by the respective set temperatures in three commercial printers. This caused a broad variation of the measured total numbers of emitted particles (TP), even when the same feedstock was operated. For the determination of TP, we followed the DE-UZ 219 test guideline. In a second round we repeated the tests with all printers adjusted to exactly the same extruder temperatures, i.e., to TE=230°C for ABS and TE=210°C for PLA. All measurements were conducted in a 1 m³ emission test chamber. Particle emissions in the size range between 4 nm and 20 μm were detected. Printing on three different printer models without temperature adjustment resulted for each of the investigated feedstocks in a variation in TP of around two orders of magnitude. After temperature adjustment, this was substantially reduced to approx. one order of magnitude and hence minimizes the bias of printer hardware on the emissions. Our findings suggest that adjustment of the extruder temperature should be mandatory in emission testing standards. It also poses a more accurate benchmark and provides more reliable emission data for evaluation of indoor air quality or for health risk assessments. In addition, a proper temperature setting is in the interest of the user. Some commercial FFF printers may have a higher actual extruder temperature than displayed and unintended overheating may not only impair the print quality but may cause unnecessarily increased exposure to particle emissions. T2 - European Aerosol Conference 2023 CY - Málaga, Spain DA - 03.09.2023 KW - Ultrafine particles KW - Thermal imaging KW - 3D printing KW - Indoor air quality KW - Emission testing PY - 2023 AN - OPUS4-58258 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tang, Chi-Long A1 - Seeger, Stefan A1 - Röllig, Mathias T1 - Improving the comparability of FFF-3D printing emission data by adjustment of the set extruder temperature N2 - Fused filament fabrication (FFF) is a material extrusion-based technique often used in desktop 3D printers. Polymeric filaments are melted and are extruded through a heated nozzle to form a 3D object in layers. The extruder temperature is therefore a key parameter for a successful print job but also one of the main emission driving factors as harmful pollutants (e.g., ultrafine particles) are formed by thermal polymer degradation. The awareness of potential health risks has increased the number of emission studies in the past years. However, studies usually refer their calculated emission data to the printer set extruder temperature for comparison purposes. In this study, we used a thermocouple and an infrared camera to measure the actual extruder temperature and found significant temperature deviations to the displayed set temperature among printer models. Our result shows that printing the same filament feedstocks with three different printer models and with identical printer set temperature resulted in a variation in particle emission of around two orders of magnitude. A temperature adjustment has reduced the variation to approx. one order of magnitude. Thus, it is necessary to refer the measured emission data to the actual extruder temperature as it poses a more accurate comparison parameter for evaluation of the indoor air quality in user scenarios or for health risk assessments. KW - Ultrafine particles KW - Infrared thermography KW - Thermocouple KW - Indoor air quality KW - FFF-3D printer PY - 2023 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:b43-572842 VL - 18 SP - 100217 PB - Elsevier Ltd. CY - Amsterdam, Niederlande AN - OPUS4-57284 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, Matthias A1 - Grimmer, Christoph A1 - de Krom, I. A1 - Maes, F. A1 - Lecuna, M. A1 - Musyanovych, A. A1 - Strzelczyk, Rebecca Skadi A1 - Horn, Wolfgang T1 - Metrological sound reference products for quality assurance and quality control measures in material emissions testing N2 - In industrialised countries more than 80% of the time is spent indoors. Products, such as building materials and furniture, emit volatile organic compounds (VOCs), which are therefore ubiquitous in indoor air. Different VOC combinations may, under certain environmental and occupational conditions, result in reported sensory irritation and health complaints. A healthy indoor environment can be achieved by controlling the sources and by eliminating or limiting the release of harmful substances into the air. One way is to use materials proven to be low emitting. Meanwhile, a worldwide network of professional commercial and non-commercial laboratories performing emission tests for the evaluation of products for interior use has been established. Therefore, comparability and metrological traceability of test results must be ensured. A laboratory’s proficiency can be proven by internal and external validation measures that both include the application of suitable reference materials. The emission test chamber procedure according to EN 16516 comprises several steps from sample preparation to sampling of test chamber air and chromatographic analysis. Quality assurance and quality control (QA/QC) must therefore be ensured. Currently, there is a lack of suitable reference products containing components relevant for the health-related evaluation of building products. The EU-funded EMPIR project 20NRM04 MetrIAQ (Metrology for the determination of emissions of dangerous substances from building materials into indoor air) aims to develop 1) gaseous primary reference materials (gPRM), which are used for the certification of gaseous (certified) reference materials (gCRM) and 2) emission reference materials (ERM). Most commercial gas standards of indoor-relevant compounds are not certified due to the lack of primary reference materials to which the project aims to contribute. The gPRM under development is a gas-phase standard containing trace levels of VOCs in nitrogen or air from the check standard according to EN 16516 (n-hexane, methyl isobutyl ketone, toluene, butyl acetate, cyclohexanone, o-xylene, phenol, 1,3,5-trimethylbenzene) with a target uncertainty of 5 %. The gPRM can be sampled into sorbent tubes to obtain transfer standards in the form of gCRM. The well characterised ERM represents a sample of a test specimen, e.g. building material, that is loaded into the emission test chamber for a period of several days and is used to evaluate the whole emission test chamber procedure. It shall have a reproducible and temporally constant compound release of less than 10 % variability over 14 days. Different approaches for retarded VOC release, such as the encapsulation of pure compounds and the impregnation of porous materials, are being tested to reach this aim. Furthermore, the design of the ERM is accompanied by the development of a numerical model for the prediction of the emissions for each of the target VOCs. The current progress of the work on both materials will be presented. T2 - CIM 2023 - 21st International Metrology Congress CY - Lyon, France DA - 07.03.2023 KW - Indoor air quality KW - VOC KW - Materials emissions testing KW - Emission reference material KW - Quality assurance/quality control PY - 2023 AN - OPUS4-57142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -