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Quality assurance and control during the mechanical heart valve components' production process is paramount to mitigate most of the valve-related complications arising from valve replacement. Nondestructive evaluation of heart valve implants with complex profiles during production is challenging due to the biocompatibility requirements and clean room assembly conditions. This study first tested the UHMWPE disc of TTK Chitra mechanical heart valve models TC1 and TC2 using Terahertz imaging in reflection mode. The UHMWPE discs were raster scanned in X-Y directions to obtain a Terahertz-C scan to locate the macro defects due to wear out, and to distinguish between the true positive and true negative samples. The results were verified with digital microscope studies. Second, this study investigates a unique relationship between Terahertz imaging in reflection mode and heart valve disc degradation due to accelerated durability study. Third, the variation of disc surface roughness due to accelerated durability test was studied by Gaussian curve fitting analysis of fast Fourier transform of the Terahertz reflections. Finally, a comparison between the TC1 and TC2 heart valve model's wear-out foot print was carried out using Terahertz C-scan. Our results imply that Terahertz time-domain spectroscopy has promising applications in NDE measurements of biocompatible implants. [ABSTRACT FROM AUTHOR]

As the field of cell and gene therapy (CGT) continues to grow, so too must the infrastructure and regulatory guidance supporting the manufacture of these potentially life-saving products—especially early-phase products manufactured at an increasing number of academic or hospital-based facilities providing decentralized (or point of care) manufacturing. An important component of current good manufacturing practices, including those regulating cell and gene therapies, is the establishment of an effective environmental monitoring (EM) program. While several guidelines for establishing an EM program are available, these guidelines do not specifically address the unique aspects of manufacturing CGT products and they do not provide real-world evidence demonstrating the effectiveness of the program. Here, we describe the establishment and evolution of an EM program in a cell therapy manufacturing facility at an academic hospital. With 10 years of EM data, we analyze the effectiveness for identifying trends in environmental conditions and highlight important findings, with the aim of providing practical evidence and guidance for the development of future early-phase EM programs. [ABSTRACT FROM AUTHOR]

INTRODUCTION. Microbiological environmental monitoring programmes for clean rooms for pharmaceutical production vary depending on the regulatory document. This is particularly evident in the experimental conditions, including the culture media used for sampling, as well as the temperature and time of incubation. To harmonise quality control procedures, it is necessary to develop a unified strategy for processing microbiological samples.AIM. This study aimed to investigate the optimal conditions for sample incubation during microbiological monitoring of clean rooms.MATERIALS AND METHODS. The study compared several culture conditions for indicator microorganisms, including Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 10231, Aspergillus brasiliensis ATCC 16404, Aspergillus fumigatus F-62, Aspergillus terreus F-1269, and Penicillium chrysogenum F-3 (the latter three strains were obtained from the Russian National Collection of Industrial Microorganisms), as well as for environmental isolates, including Staphylococcus epidermidis, Kocuria rosea, Micrococcus luteus, Bacillus spp., and Sphingomonas paucimobilis. The culture media used were trypticase soy agar (TSA), Sabouraud's dextrose chloramphenicol agar (SDCA), and Reasoner’s 2A agar (R2A). The incubation regimes used were as follows: 2 days at 30–35 ºC and then 3 days at 20–25 ºC; 3 days at 20–25 ºC and then 2 days at 30–35 ºC; 48–72 hours at 30–35 ºC (for aerobic bacteria); 5–7 days at 20–25 ºC (for yeasts and moulds).RESULTS. The comparison showed no statistically significant differences between the results obtained with TSA and R2A under different temperatureconditions. The germination rates of environmental isolates grown on TSA were significantly lower (by 19–37%) in the two-tiered incubation scheme that started at a lower temperature. The study identified groups of microorganisms requiring special culture conditions for microbiological environmental monitoring (bacteria with suppressed physiological functions and moulds).CONCLUSIONS. The study confirmed the need to standardise microbiological testing used in environmental monitoring and to provide for its proper regulation by drafting a general monograph on the matter. The authors demonstrated the applicability of both TSA and R2A as culture media for microbiological environmental monitoring. Currently, the use of a two-tiered incubation scheme with one non-selective culture medium requires validation on a case-by-case basis. Although the sequence of temperature levels did not affect the germination rates of microorganisms significantly, the incubation regime starting at a higher temperature (30–35 ºС) was determined as preferable for bacterial environmental isolates.

Background: Limited research has delved into the effects of work characteristics on premenstrual symptoms (PMS) in women, which can influence work performance and overlook potential hazards for women in their work environments. This study aimed to investigate the impact of shift work and working in a clean room on premenstrual symptoms, menstrual status, and menstrual pain among employed females in an electronics manufacturer. Methods: A retrospective cohort study was conducted on menstruating female employees between August and December 2014, aged 18–55, who received regular employee health checks. Questionnaires were designed to collect information on demographics, personal lifestyle, menstrual status, menstrual pain scores, and self-reported premenstrual symptoms. Results: Among 7,193 participants, 18.6% reported moderate to severe menstrual pain affecting their work. Female workers who reported shift work showed an increased prevalence of moderate to severe premenstrual symptoms, including fatigue (RR = 1.20), somatic discomforts (RR = 1.04), diarrhea (RR = 1.04), and tension (RR = 1.05). Additionally, shift work was associated with an elevated risk of experiencing a moderate or significant impact of menstrual pain on work (RR = 1.03), menstrual irregularity (RR = 1.30), and high menstrual pain (RR = 1.23). Working in a clean room was associated with an increased risk of high menstrual pain (RR = 1.13). Subjects working shifts in a clean room had the highest pain scores compared to the other groups. Conclusion: This study underscores the association of work-related factors on PMS in female employees. Our findings contribute to a better understanding of premenstrual symptoms in female workers with different work characteristics, emphasizing the potential hazards of work-related factors on female employees.

Global warming has led to the continuous deterioration of the living environment, in which air quality directly affects human health. In addition, the severity of the COVID-19 pandemic has further increased the attention to indoor air quality. Indoor clean air quality is not only related to human health but also related to the quality of the manufacturing environment of clean rooms for numerous high-tech processes, such as semiconductors and packaging. This paper proposes a comprehensive model for evaluating, analyzing, and improving the operational performance of air cleaning equipment. Firstly, three operational performance evaluation indexes, such as the number of dust particles, the number of colonies, and microorganisms, were established. Secondly, the 100(1 −   α)% upper confidence limits of these three operational performance evaluation indexes were deduced to construct a fuzzy testing model. Meanwhile, the accumulated value of ϕ was used to derive the evaluation decision-making value. The proposed model can help companies identify the key quality characteristics that need to be improved. Furthermore, the competitiveness of cooperative enterprises towards smart manufacturing can be strengthened, so that enterprises can not only fulfill their social responsibilities while developing the economy but also take into account the sustainable development of enterprises and the environment. [ABSTRACT FROM AUTHOR]

The present study addresses advanced monitoring techniques for particles and airborne molecular contaminants (AMCs) in cleanroom environments, which are crucial for ensuring the integrity of semiconductor manufacturing processes. We focus on quantifying particle levels and a representative AMC, hydrogen chloride (HCl), having known detrimental effects on equipment longevity, product yield, and human health. We have developed a compact laser sensor based on open-path cavity ring-down spectroscopy (CRDS) using a 1742 nm near-infrared diode laser source. The sensor enables the high-sensitivity detection of HCl through absorption by the 2-0 vibrational band with an Allan deviation of 0.15 parts per billion (ppb) over 15 min. For quantifying particle number concentrations, we examine various detection methods based on statistical analyses of Mie scattering-induced ring-down time fluctuations. We find that the ring-down distributions' 3rd and 4th standard moments allow particle detection at densities as low as ~105 m−3 (diameter > 1 μm). These findings provide a basis for the future development of compact cleanroom monitoring instrumentation for wafer-level monitoring for both AMC and particles, including mobile platforms. [ABSTRACT FROM AUTHOR]

Prepregs are highly dependent on the resin, its chemical composition, and physical properties. Resin is the perishable part of prepreg materials and usually requires controlled storage, otherwise, its processability and properties may be affected. Oven curing prepregs are recognized to have longer life out of the freezer than those designed to cure in autoclave, and one of them, prepreg 2511, is the focus of this research. Prepreg 2511 has a formal out-time limit of 28 days at clean room environment (23°C/50% relative humidity), and 24 months shelf life, when frozen at −18°C, while common prepreg designed to be cured in autoclave, usually have 15 days of out-time and 12 months of shelf-life. It is known that the real shelf life and out time of epoxy-based materials tends to be longer than suppliers' recommendation. Aiming to assess 2511 performance after those 28 days of exposure to clean room ambient, during and after 24 months in freezer; the material was exposed to this environmental condition for more than 28 days and tested periodically using different methods, including, Differential Scanning Calorimeter, High-Performance Liquid Chromatography tack, among others. In resume, the goal of this research was to identify 2511 longest out life without losing its properties and which of the tests used during these experiments would be more sensitive to capture its aging. [ABSTRACT FROM AUTHOR]

The NUOVA OFFICINA ASSERGI (NOA) is a new facility for the production and integration of large-area silicon photodetectors operating at cryogenic temperatures. Silicon photomultipliers are proving to be a promising technology for next-generation experiments searching for rare events in underground laboratories. New photosensor technology with high performance at cryogenic temperature has been developed by Fondazione Bruno Kessler (FBK) and integrated at Laboratori Nazionali del Gran Sasso (LNGS) into large-area optical units, thus opening the frontiers toward the realization of scalable liquid argon experiments probing dark matter. The massive production of such detectors is now feasible in NOA, a clean room of 421 m2 designed to operate in a radon-free mode. NOA, commissioned and operational at LNGS, hosts the most advanced packaging machines and electronic test facilities for the integration of silicon devices in a dust-controlled environment. The infrastructure layout is split into two experimental areas: one for the production of electronic devices and cryogenic temperature tests and the other for operating with large detector installations. The NOA facility can be operated with a radon abatement system, making it a unique facility for packaging and testing SiPM-based photosensors and for assembling detector components in a radon-free environment. Therefore, NOA supports the deployment of underground experiments at LNGS and the development of new technologies for the search of rare events, such as dark matter and neutrinoless double-beta decay. [ABSTRACT FROM AUTHOR]

The seamless integration of wearable devices into user‐friendly and cost‐effective healthcare systems requires constituent materials with high degrees of flexibility, stretchability, and adhesive properties without compromising performance during dynamic body movements. This study proposes a liquid metal (LM)‐based multimodal skin‐mountable sensor platform using polydimethylsiloxane tuned for enhanced stretchability and stickiness (sPDMS) to fully leverage the LM's deformability. A highly accessible end‐to‐end fabrication approach is proposed for multifunctional LM sensors from modeling to fabrication and packaging, all achieved without the need for cleanroom facilities or special equipment. The LM‐based facile fabrication process tailored for sPDMS enables an adhesive‐free sensor patch with microfluidic channels of 100 µm width and stretchability up to 100%. A new analytical model provides enhanced estimation on the electromechanical behavior of LM channels compared with existing models. The funnel‐assisted LM filling and tape‐based channel sealing methods enable simple packaging of LM channels with robust external interconnection and direct skin‐interfaced monitoring. The feasibility of this healthcare platform is demonstrated through a multimodal sensor patch with electromechanical and electrophysiological functionalities. The proposed technology addresses current challenges in the cost and complexity of microfabrication, expanding the boundaries of wearable devices for highly accessible and personalized healthcare devices. [ABSTRACT FROM AUTHOR]

Ventilation systems of operating rooms (ORs) are significantly important in preventing postoperative wound infections that can cause morbidity and mortality after surgery in or out of the hospital. This study aims to identify the optimum overpressure for efficient operation while reducing the risk of surgical site infections (SSIs) based on the actual OR with the help of computational fluid dynamics. The species transport model, Lagrangian discrete phase model, and turbulent standard k- ε model are mainly used for the transient numerical study to improve the performance of the OR and reduce SSI cases. Four OR schemes were initially calculated for the best location of the patient on the surgical table. The results revealed that the modified position 90˚ is the best location with the minimum CO2 and BCP concentrations. The investigated operating room could host up to ten surgical members with the optimum overpressure of 5.89 Pa and 0.56 m/s of supply velocity under the standard cleanliness level. Modifying the supply surface area will enhance the performance of the operating room by providing a cleaner zone and maintaining the desired room pressure, even with a low airflow rate. This optimization scheme could guide practical applications in all positively pressurized operating rooms to address issues related to overpressure effects. [ABSTRACT FROM AUTHOR]

Purpose: This study investigated the influence of cleanroom conditions on the discard rates of donor corneas in a German university eye bank. Methods: Discard rates were analysed from 2017 to 2020 at the LIONS Cornea Bank at Saarland University Medical Center. 1941 corneas from 971 donors were included. 1262 corneas (65.1%) were stored in a class D cleanroom from 2017 to 2019 and processed in a cleanroom class A sterile bank (group 1). 679 corneas (34.9%) were continuously stored in a class B cleanroom and processed in a class A cleanroom safety cabinet in the same room from 2019 to 2020 (group 2). The target parameter of this work was the number of contamination‐related discards. Although they cannot be influenced by the spatial conditions, the discards due to insufficient endothelial quality, serology, contraindications, scars and technical causes were also recorded. Statistical analysis was performed using SPSS and various testing procedures. Results: In group 1, significantly more corneas were discarded due to positive serology (6.9%|3.8%, p = 0.020). There was no significant change between both groups for either contamination or the other reasons for discard. Conclusion: Optimization of hygiene standards from cleanroom class D to B did not reduce contamination. Serology, endothelial quality, medical contraindications and the presence of scars cannot be influenced by cleanroom conditions. [ABSTRACT FROM AUTHOR]

The increasing number of fires in semiconductor factories requires new approaches to fire safety. It is important to study the specifics of the activities of companies that use potentially flammable materials in production, such as air filtration units, electrical cables and floor panels. The aim of the study was therefore to determine the level of fire risk in the clean rooms of these companies by means of real fire experiments. As a result, a fire risk assessment of the main combustible materials such as air filtration units, electrical cables and floor panels in the plenum room on the top floor of the cleanroom was carried out. The results of the experiment showed a low ignition propensity of the air filtration unit and limited fire propagation in the event of ignition. High calorific materials, such as fibreglass in filters, were identified as increasing the risk. Based on this, it was proposed to replace these materials with flame retardant materials and to improve the stop/fire control systems of the air filtration units. The results obtained in the study should be used for the development of technical recommendations for improving fire safety in critical premises at semiconductor factories. [ABSTRACT FROM AUTHOR]

The assembly of van der Waals (vdW) heterostructures using 2D material transfer systems has revolutionized the field of materials science, enabling the development of novel electronic and optoelectronic devices and the probing of emergent phenomena. The innovative vertical stacking methods enabled by these 2D material transfer systems are central to constructing complex devices, which are often challenging to achieve with traditional bottom-up nanofabrication techniques. Over the past decade, vdW heterostructures have unlocked numerous applications leading to the development of advanced devices, such as transistors, photodetectors, solar cells, and sensors. However, achieving consistent performance remains challenging due to variations in transfer processes, contamination, and the handling of air-sensitive materials, among other factors. Several of these challenges can be addressed through careful design considerations of transfer systems and through innovative modifications. This mini-review critically examines the current state of transfer systems, focusing on their design, cost-effectiveness, and operational efficiency. Special emphasis is placed on low-cost systems and glovebox integration essential for handling air-sensitive materials. We highlight recent advancements in transfer systems, including the integration of cleanroom environments within gloveboxes and the advent of robotic automation. Finally, we discuss ongoing challenges and the necessity for further innovations to achieve reliable, cleaner, and scalable vdW technologies for future applications. [ABSTRACT FROM AUTHOR]

The establishment of a compliant radiopharmacy facility within a university setting is crucial for supporting fundamental and preclinical studies, as well as for the production of high-quality radiopharmaceuticals for clinical testing in human protocols as part of Investigational New Drug (IND) applications that are reviewed and approved by the U.S. Food and Drug Administration (FDA). This manuscript details the design and construction of a 550 ft2 facility, which included a radiopharmacy and a radiochemistry laboratory, to support radiopharmaceutical development research and facilitate translational research projects. The facility was designed to meet FDA guidelines for the production of aseptic radiopharmaceuticals in accordance with current good manufacturing practice (cGMP). A modular hard-panel cleanroom was constructed to meet manufacturing classifications set by the International Organization of Standardization (ISO), complete with a gowning room and an anteroom. Two lead-shielded hot cells and two dual-mini hot cells, connected via underground trenches containing shielded conduits, were installed to optimize radioactive material transfer while minimizing personnel radiation exposure. Concrete blocks and lead bricks provided sufficient and cost-effective radiation shielding for the trenches. Air quality was controlled using pre-filters and high-efficiency particulate air (HEPA) filters to meet cleanroom ISO7 (Class 10,000) standards. A laminar-flow biosafety cabinet was installed in the cleanroom for preparation of sterile dose vials. Noteworthy was a laminar-flow insert in the hot cell that provided a shielded laminar-flow sterile environment meeting ISO5 (class 100) standards. The design included the constant control and monitoring of differential air pressures across the cleanroom, anteroom, gowning room, and controlled research space, as well as maintenance of temperature and humidity. The facility was equipped with state-of-the-art equipment for quality control and release testing of radiopharmaceuticals. Administrative controls and standard operating procedures (SOPs) were established to ensure compliance with manufacturing standards and regulatory requirements. Overall, the design and construction of this radiopharmacy facility exemplified a commitment to advancing fundamental, translational, and clinical applications of radiopharmaceutical research within an academic environment. [ABSTRACT FROM AUTHOR]

As part of a publicly funded cooperation project, novel high-performance lubricants (oils, greases, assembly pastes) based on ionic liquids and with the addition of specific micro- or nanoparticles are to be developed, which are adapted in their formulation for use in applications where their negligible vapor pressure plays an important role. These lubricants are urgently needed for applications in cleanrooms and high vacuum (e.g., pharmaceuticals, aerospace, chip manufacturing), especially when the frequently used perfluoropolyethers (PFPE) are no longer available due to a potential restriction of per- and polyfluoroalkyl substances (PFAS) due to European chemical legislation. Until now, there has been a lack of suitable laboratory testing technology to develop such innovative lubricants for extreme niche applications economically. There is a large gap in the tribological test chain between model testing, for example in the so-called spiral orbit tribometer (SOT) or ball-on-disk test in a high-frequency, linear-oscillation test machine (SRV-Tribometer from German "Schwing-Reib-Verschleiß-Tribometer"), and overall component testing at major space agencies (ESA—European Space Agency, NASA—National Aeronautics and Space Administration) or their service providers like the European Space Tribology Laboratory (ESTL) in Manchester. A further aim of the project was therefore to develop an application-orientated and economical testing methodology and testing technology for the scientifically precise evaluation and verifiability of the effect of ionic liquids on tribological systems in cleanrooms and under high vacuum conditions. The newly developed test rig is the focus of this publication. It forms the basis for all further investigations. [ABSTRACT FROM AUTHOR]

Even though, nowadays, most medicines are manufactured industrially, patients may have medical needs that can only be met by a tailor-made approach. This requires the availability of pharmacy preparations made under Good Manufacturing Practice (GMP) conditions. An efficient hand hygiene practice is essential herewith, especially if sterile products that are prepared in a cleanroom are concerned. The effectiveness of hand washing and hand disinfection procedures greatly relies on adequate training. We carried out an observational cross-sectional pilot study aimed at optimizing hand hygiene training with objective and measurable quality assessments using an ultraviolet (UV) dye. Practical acceptance criteria for qualifying personnel through this method were set and evaluated. In total, 25 GMP-qualified cleanroom operators washed and disinfected their hands with UV dye hand wash lotion and UV dye hand alcohol, respectively. To obtain a proof-of-concept, the results were judged based on adherence to the WHO six-step protocol and associated acceptance criteria. Commonly missed areas were brought to light, and the influence of procedure duration was investigated. UV-dye-based assessments appeared to be more valuable in hand disinfection than in hand washing. In both procedures, the back of the hands and the thumbs were frequently missed. This underpins the need for enhanced and repeated education on hand washing and disinfection. Additionally, a dry skin gave rise to extra cleaning challenges. From this pharmacy practice pilot study with a focus on pharmaceutical product care, it may be concluded that the application of UV-dye-based assessments offers valuable insights for pharmacists to optimize hand hygiene, thereby increasing the safety of tailor-made medicines and on-site preparations. [ABSTRACT FROM AUTHOR]

Building Information Modeling (BIM) has been widely used in the past decade to enhance the design quality of Heating, Ventilation, and Air Conditioning (HVAC) systems. However, in specialized areas such as pharmaceutical facilities, HVAC design has traditionally relied on Computer-Aided Design (CAD) drawings. This conventional approach does not allow for the simulation of temperature distribution or the verification of system efficiency, which may lead to design failures. To address these challenges in pharmaceutical facilities, this study proposed a BIM-based approach for optimizing HVAC design with Computational Fluid Dynamics (CFD). By employing CFD to simulate the dynamic airflow conditions of pharmaceutical clean rooms, the effectiveness of HVAC systems can be verified. A case study of a clean room HVAC design is presented to demonstrate the workflow. The results of the case study indicated that the pharmaceutical temperature requirements were met within 1 °C during the design optimization simulation, and there was a 95% match in the 72 h temperature mapping test during site validation. The results confirmed that using CFD with BIM not only successfully simulates the design intentions of indoor air quality but also suggests HVAC system optimization for the required clean room design. The findings of this paper contribute to the body of knowledge on overcoming the limitations of the traditional CAD-based HVAC design process and provide valuable insights on optimizing HVAC design with BIM and CFD technologies. [ABSTRACT FROM AUTHOR]

The support system of heat, ventilation, and air conditioning (HVAC) in manufacturing plants plays an important role in the optimum efficiency of the production system. Failure to support adequate HVAC on the production floor will cause production defects, stoppage time, unplanned machine downtime, and other related issues. These issues highly affect those products that require dedicated temperature, pressure, and humidity, such as production clean rooms, food industries, and pharmaceutical products. Thus, this study aims to develop and apply the specific reliability assessment in an investigation of HVAC, focusing on the production of pharmaceutical products. In this study, the selected statistical quality tools have been applied in the evaluation and prediction of the HVAC failure and maintenance process. To ensure suitable tools and methods will be applied, a systematic approach has been developed consisting of six steps towards effective maintenance of the HVAC system. The main purpose of the application quality tools such as check sheet, Pareto chart, scatter plot, and probability plot was to evaluate the historical failure data and then to predict the potential future failure through analysis of Mean Time Between Failure (MTBF) in steps 1 to 4. To ensure the developed approach successfully implemented the Failure Mode and Effects Analysis (FMEA) in step 5, the corrective action plan was suggested in step 6. Once the systematic approach of HVAC preventive maintenance had been successfully developed, it was then implemented in the selected production floor of the pharmaceutical industry. The execution of this developed systematic approach to predicting the HVAC resulted in an increase in the total MTBF from 529.50 minutes to 778.23 minutes. It showed an improvement of 47% after the implementation of the developed systematic approach. The obtained results showed that reliability assessment was important for the optimization of production efficiency. [ABSTRACT FROM AUTHOR]

Existing research of non-unidirectional cleanrooms generally suggests that lower-side return air outlets provide better control effect on indoor particle concentration. As a result, there has been relatively less focus on return air outlets. However, installing return air outlets oriented towards operators as particle emission sources can reduce the impact on process layout and improve space utilization, while also provide less impact from upper particle emission sources on the workbench area. To investigate the characteristics of return air outlet for operators (abbreviated as H), this study compared the particle concentration distribution, non—uniformity, and purification efficiency of return air oultet H and the traditional lower-side (abbreviated as L) return air outlets by experiments and CFD simulations. Based on the theory of mass conservation, the expression of required air supply volume under equivalent cleanroom conditions was derived. Under corresponding experimental and simulation conditions, the particle concentration differences range from 2.0% to 12.7% for return air outlet H and from 12.4% to 33.2% for return air outlet L, and these differences gradually decrease with the air exchange rate (ACH) increases. The results show that ACH = 20 is sufficient for cleanliness requirements with return air outlet H when there is one person in the cleanroom, while a higher rate of ACH = 35 is needed when there are two persons. Although lower-side return air outlets have certain potential for reducing particle concentration in the cleanroom, increasing the air exchange rate remains the most effective method to control indoor particle concentration. Compared to the traditional lower-side return air outlet L, the ranges of the non-uniformity coefficients for return air outlet H and L are 0.50 to 0.67 and 0.45 to 0.53, respectively. The average non-uniformity coefficient differs by 11.9%, and there is not a significant difference in uniformity with more than 20 air changes per hour. The use of return air outlets H only requires an additional 11% of air supply volume to achieve the same cleanliness, demonstrating its effectiveness in controlling particle concentration. It is suitable for cleanrooms with higher requirements for workbenches and for cleanrooms with restricted floor usage or requiring flexible layouts. The study also explores the impact of width of return air outlet oriented towards operators as particle emission sources, the results show that the larger-sized outlets facilitate the particle discharge and control the particle distribution inside the room. [ABSTRACT FROM AUTHOR]

A prototype cleanroom for hazardous testing and handling of satellites prior to launcher encapsulation, satisfying the ISO8 standard has been designed and analyzed in terms of performances. Unsteady Reynolds Averaged Navier-Stokes (URANS) models have been used to study the related flow field and particulate matter (PM) dispersion. The outcomes of the URANS models have been validated through comparison with equivalent large-eddy simulations. Special attention has been paid to the location and shape of the air intakes and their orientation in space, in order to balance the PM convection and diffusion inside the cleanroom. Forming a cyclone-type flow pattern inside the cleanroom is a key to maintaining a high ventilation efficiency. [ABSTRACT FROM AUTHOR]

The motion effect on the contaminant dispersion is a key parameter in cleanrooms. This parameter is ignored in many experimental and numerical studies because of its complexities, but could cause errors in the obtained results. In real situations, particularly in the isolating rooms and cleanrooms, the motion that is usually caused by the human moving and doors opening and closing leads to considerable flow changes that require attention. The present study aimed to explore studies that noticed and studied different aspects of the subject and to summarize the areas with priority for further investigation. Modeling the problem using experimental and numerical approaches requires steps and settings that are described in the experimental and numerical sections. The motion analysis is divided into two sections of human and door motions, covering the key findings of previous and recent publications, and concluding the required future studies. The results of approximately fifty published studies have revealed important findings related to cleanroom class degradation, temperature gradient reduction, increased contamination and secondary flow depth, and particle settlement on patients. These studies have shown that the ventilation system may need to be redesigned. Furthermore, it is crucial to consider the motion in both experimental and numerical studies based on the application. Additional research is necessary to further understand these findings. [ABSTRACT FROM AUTHOR]

Background Massive modular endoprostheses have become a primary means of reconstruction after oncologic resection of a lower extremity tumor. These implants are commonly made with cobalt-chromium alloys that can undergo wear and corrosion, releasing cobalt and chromium ions into the surrounding tissue and blood. However, there are few studies about the blood metal levels in these patients. Question/purpose What is the whole blood cobalt and chromium ion level in patients with massive modular endoprostheses? Methods We performed a cross-sectional study of our total joints registry to identify patients with a history of an endoprosthetic reconstruction performed at our institution. Patients who were alive at the time of our review in addition to those undergoing an endoprosthetic reconstruction after an oncologic resection were included. Whole blood samples were obtained from 27 (14 male and 13 female) patients with a history of a lower extremity oncologic endoprosthesis. The median time from surgery to blood collection was 8 years (range 6 months to 32 years). Blood samples were collected and stored in metal-free ethylenediaminetetraacetic acid tubes. Samples were analyzed on an inductively coupled plasma mass spectrometer in an International Organization for Standardization seven-class clean room using polytetrafluoroethylene-coated instruments to reduce the risk of metal contamination. The analytical measuring range was 1 to 200 ng/mL for chromium and cobalt. Cobalt and chromium levels were considered elevated when the blood level was $ 1 ppb. Results Cobalt levels were elevated in 59% (16 of 27) of patients, and chromium levels were elevated in 26% (seven of 27). In patients with elevated metal ion values, 15 of 17 patients had a reconstruction using a Stryker/Howmedica Global Modular Replacement System implant. Conclusion Blood metal levels were elevated in patients who received reconstructions using modular oncology endoprostheses Future work is needed to establish appropriate follow-up routines and determine whether and when systemic complications occur because of elevated metal levels and how to potentially address these elevated levels when complications occur. Prospective and retrospective collaboration between multiple centers and specialty societies will be necessary to address these unknown questions in this potentially vulnerable patient group. Level of Evidence Level IV, therapeutic study. [ABSTRACT FROM AUTHOR]

Part 1 of this tutorial addressed how environmental contamination may be minimized by using proper personal analytical practices, sample preparation environmental suggestions, avoidance of glass and low purity quartz contact with samples and standards during sample collection and preparation, and appropriate choices of high purity solvents during sample collection and preparation. Part 2 continues the discussion in terms of minimizing sample contamination issues by using high purity polymer materials for sample collection and preparation, as well as discuss the differences between instrument and method limits of detection (LODs). Accepted and appropriate procedures for calculating method LODs are related to variability in instrument response and unavoidable environmental contamination during even the cleanest sample preparation. Adherence to such practices will help analysts avoid false positives and report results with a high level of confidence., Investigation of materials for trapping aerosols with minimum metal contamination compared to glass and low purity quartz fiber filters led to investigation of membrane filters manufactured from polymers. Unfortunately, polymer [...]