151 research outputs found
Recommended from our members
Metals Analysis Results for the Structural Qualification Test Series (SQTS) 01 - 05.
Enclosed is the report summarizing the metals analysis results at the Contained Firing Facility (CFF), during SQTS 01 - 05. This metals analysis includes evaluation of a bulk dust and surface swipe sampling protocol during the testing series that obtained samples at 3 primary locations in the CFF chamber area. The sampling protocol for each of the bulk dust samples involves an assessment of the concentration for 20 different metals, the oxidation state of selected metals, a particle size selective analysis, and morphological information. In addition, surface swipes were taken during SQTS 05 on the equipment and personnel door frames to indicate the characteristics of airborne metals due to leakage past the gasket seals. The bulk dust metals analysis indicates a nearly complete conversion of the aluminum casing to an oxide form with an even split between spherical and non-spherical morphology. Size selective analysis shows 83% of the particulates are in the inhalable size range of less than 100 microns and 46% are in the respirable range of less than 10 microns. Combining metals analysis and leakage results indicate the potential for a problematic personal exposure to metals external to the chamber unless modifications are made. Please feel free to call me at 2-8904 if you have any questions or if I may be of further service
Recommended from our members
Heart to heart - a custodian journal on grassroots ergonomics
When we first requested to speak at the American Society of Safety Engineer`s Professional Development Conference in Seattle, Washington, the theme we had in mind for this program paper was quite different. It definitely was not anything like our title, `Heart to Heart` implies. It was more formal and traditional. Give you figures, diagrams and the like. But two years later, we have come to another conclusion, to tell you the story about how a group of custodians and health & safety professionals dreamed big dreams and they came true. In order to understand what occurred, we first need to start at the very beginning with the Custodian Quality Improvement Team (CQIT). This group had been formed by the Plant Engineering Department at the Lawrence Livermore National Laboratory (LLNL) located in Livermore, California. LLNL is operated by the University of California for The U.S.Department of Energy. It is the premier applied physics research laboratory in the world. Plant Engineering (PE) is much like a Public Works Department. PE has all of the crafts, such as plumbers and electricians, who do maintenance-type work, as well as the engineering and construction employees. PE maintain the utilities, constructs new buildings and takes care of old ones. They take of the roads and clean the buildings and landscape the campus. So the Custodian Shop and its some 150 employees is a member of the PE family so to speak. The CQIT had decided to investigate ways they could reduce the number of injuries they were having. They invited health and safety professionals, David Zalk (an Industrial Hygienist) and Jack Tolley (Safety Engineer) to consult with them about this. They are both Hazards Control Team 4 members at LLNL. They were both interested in ergonomics and suggested that an approach to reducing their injuries might lie in studying how the custodians actually do their work. David has extensive training in ergonomics, and Jack simply had a long-time interest in ergonomics for some 30 years, describing himself as a `learned layman.
Recommended from our members
History and Evolution of Control Banding: A Review
Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents often encountered in the workplace. The original CB model was developed within the pharmaceutical industry; however, the modern movement involves models developed for non-experts to input hazard and exposure potential information for bulk chemical processes, receiving control advice as a result. The CB approach utilizes these models for the dissemination of qualitative and semi-quantitative risk assessment tools being developed to complement the traditional industrial hygiene model of air sampling and analysis. It is being applied and tested in small and medium size enterprises (SMEs) within developed countries and industrially developing countries; however, large enterprises (LEs) have also incorporated these strategies within chemical safety programs. Existing research of the components of the most available CB model, the Control of Substances Hazardous to Health (COSHH) Essentials, has shown that exposure bands do not always provide adequate margins of safety, that there is a high rate of under-control errors, that it works better with dusts than with vapors, that there is an inherent inaccuracy in estimating variability, and that when taken together the outcomes of this model may lead to potentially inappropriate workplace confidence in chemical exposure reduction in some operations. Alternatively, large-scale comparisons of industry exposure data to this CB model's outcomes have indicated more promising results with a high correlation seen internationally. With the accuracy of the toxicological ratings and hazard band classification currently in question, their proper reevaluation will be of great benefit to the reliability of existing and future CB models. The need for a more complete analysis of CB model components and, most importantly, a more comprehensive prospective research process remains and will be important in understanding implications of the model's overall effectiveness. Since the CB approach is now being used worldwide with an even broader implementation in progress, further research toward understanding its strengths and weaknesses will assist in its further refinement and confidence in its ongoing utility
Recommended from our members
Control Banding and Nanotechnology Synergist
The average Industrial Hygienist (IH) loves a challenge, right? Okay, well here is one with more than a few twists. We start by going through the basics of a risk assessment. You have some chemical agents, a few workers, and the makings of your basic exposure characterization. However, you have no occupational exposure limit (OEL), essentially no toxicological basis, and no epidemiology. Now the real handicap is that you cannot use sampling pumps, cassettes, tubes, or any of the media in your toolbox, and the whole concept of mass-to-dose is out the window, even at high exposure levels. Of course, by the title, you knew we were talking about nanomaterials (NM). However, we wonder how many IHs know that this topic takes everything you know about your profession and turns it upside down. It takes the very foundations that you worked so hard in college and in the field to master and pulls it out from underneath you. It even takes the gold standard of our profession, the quantitative science of exposure assessment, and makes it look pretty darn rusty. Now with NM there is the potential to get some aspect of quantitative measurements, but the instruments are generally very expensive and getting an appropriate workplace personal exposure measurement can be very difficult if not impossible. The potential for workers getting exposures, however, is very real, as evidenced by a recent publication reporting worker exposures to polyacrylate nanoparticles in a Chinese factory (Song et al. 2009). With something this complex and challenging, how does a concept as simple as Control Banding (CB) save the day? Although many IHs have heard of CB, most of their knowledge comes from its application in the COSHH Essentials toolkit. While there is conflicting published research on COSHH Essentials and its value for risk assessments, almost all of the experts agree that it can be useful when no OELs are available (Zalk and Nelson 2008). It is this aspect of CB, its utility with uncertainty, that attracted international NM experts to recommend this qualitative risk assessment approach for NM. However, since their CB recommendation was only in theory, we took on the challenge of developing a working toolkit, the CB Nanotool (see Zalk et al. 2009 and Paik et al. 2008), as a means to perform a risk assessment and protect researchers at the Lawrence Livermore National Laboratory. While it's been acknowledged that engineered NM have potentially endless benefits for society, it became clear to us that the very properties that make nanotechnology so useful to industry could also make them dangerous to humans and the environment. Among the uncertainties and unknowns with NM are: the contribution of their physical structure to their toxicity, significant differences in their deposition and clearance in the lungs when compared to their parent material (PM), a lack of agreement on the appropriate indices for exposure to NM, and very little background information on exposure scenarios or populations at risk. Part of this lack of background information can be traced to the lack of risk assessments historically performed in the industry, with a recent survey indicating that 65% of companies working with NM are not doing any kind of NM-specific risk assessment as they focus on traditional PM methods for IH (Helland et al. 2009). The good news is that the amount of peer-reviewed publications that address environmental, health and safety aspects of NM has been increasing over the last few years; however, the percentage of these that address practical methods to reduce exposure and protect workers is orders of magnitude lower. Our intent in developing the CB Nanotool was to create a simplified approach that would protect workers while unraveling the mysteries of NM for experts and non-experts alike. Since such a large part of the toxicological effects of both the physical and chemical properties of NM were unknown, not to mention changing logarithmically as new NM research continues growing, we needed to account for this lack of information as part of the CB Nanotool's risk assessment. We chose a standardized 4 X 4 risk matrix (see figure 1) as our starting point, working with the severity parameters on one axis and the probability parameters on the other. The development of the severity axis was certainly the hardest part of our effort. This required the dissection of NM and its physicochemical properties which are often unknown, adding information on the PM which is far more available, and somehow scoring these input factors in a manner that appropriately weighted each factor. We decided to give unknown input factors a score of 75% of the points for each category, because otherwise the instinct of considering it as extremely dangerous would kick in and the highest level of control would almost always be the outcome
FLASHlight MRI in real time - a step towards Star Trek medicine
This work describes a dynamic magnetic resonance imaging (MRI) technique for local scanning of the human body with use of a handheld receive coil or coil array. Real-time MRI is based on highly undersampled radial gradient-echo sequences with joint reconstructions of serial images and coil sensitivity maps by regularized nonlinear inversion (NLINV). For this proof-of-concept study, a fixed slice position and field-of-view (FOV) were predefined from the operating console, while a local receive coil (array) is moved across the body—for the sake of simplicity by the subject itself. Experimental realizations with a conventional 3 T magnet comprise dynamic anatomic imaging of the head, thorax and abdomen of healthy volunteers. Typically, the image resolution was 0.75 to 1.5 mm with 3 to 6 mm section thickness and acquisition times of 33 to 100 ms per frame. However, spatiotemporal resolutions and contrasts are highly variable and may be adjusted to clinical needs. In summary, the proposed FLASHlight MRI method provides a robust acquisition and reconstruction basis for future diagnostic strategies that mimic the usage of ultrasound. Necessary extensions for this vision require remote control of all sequence parameters by a person at the scanner as well as the design of more flexible gradients and magnets
Recommended from our members
Application of a pilot control banding tool for risk level assessment and control of nanoparticle exposures
Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents that are found in the workplace in the absence of firm toxicological and exposure data. These strategies may be particularly useful in nanotechnology applications, considering the overwhelming level of uncertainty over what nanomaterials and nanotechnologies present as potential work-related health risks, what about these materials might lead to adverse toxicological activity, how risk related to these might be assessed, and how to manage these issues in the absence of this information. This study introduces a pilot CB tool or 'CB Nanotool' that was developed specifically for characterizing the health aspects of working with engineered nanoparticles and determining the level of risk and associated controls for five ongoing nanotechnology-related operations being conducted at two Department of Energy (DOE) research laboratories. Based on the application of the CB Nanotool, four of the five operations evaluated in this study were found to have implemented controls consistent with what was recommended by the CB Nanotool, with one operation even exceeding the required controls for that activity. The one remaining operation was determined to require an upgrade in controls. By developing this dynamic CB Nanotool within the realm of the scientific information available, this application of CB appears to be a useful approach for assessing the risk of nanomaterial operations, providing recommendations for appropriate engineering controls, and facilitating the allocation of resources to the activities that most need them
High-resolution myocardial T1 mapping using single-shot inversion-recovery fast low-angle shot MRI with radial undersampling and iterative reconstruction.
To develop a novel method for rapid myocardial T1 mapping at high spatial resolution. METHODS: The proposed strategy represents a single-shot inversion-recovery (IR) experiment triggered to early diastole during a brief breathhold. The measurement combines an adiabatic inversion pulse with a real-time readout by highly undersampled radial FLASH, iterative image reconstruction and T1 fitting with automatic deletion of systolic frames. The method was implemented on a 3 T MRI system using a GPU-equipped bypass computer for online application. Validations employed a T1 reference phantom including analyses at simulated heart rates from 40 to 100 bpm. In vivo applications involved myocardial T1 mapping in short-axis views of healthy young volunteers. RESULTS: At 1 mm in-plane resolution and 6 mm section thickness, the IR measurement could be shortened to 3 s without compromising T1 quantitation. Phantom studies demonstrated T1 accuracy and high precision for values ranging from 300 to 1500 ms and up to a heart rate of 100 bpm. Similar results were obtained in vivo yielding septal T1 values of 1246 ± 24 ms (base), 1256 ± 33 ms (mid-ventricular) and 1288 ± 30 ms (apex), respectively (mean ± SD, n=6). CONCLUSION: Diastolic myocardial T1 mapping with use of single-shot inversion-recovery FLASH offers high spatial resolution, T1 accuracy and precision, practical robustness and speed. Advances in knowledge: The proposed method will be beneficial for clinical applications relying on native and post-contrast T1 quantitation
Recommended from our members
Material Evaluation Test Series 07, 08A, and 09A
This research effort examines the post-detonation environmental, safety, health and operational aspects of experimental explosive tests with mercury. Specific experimental information is necessary for the evaluation of post-detonation by-products in comparison with those potentially resulting from mercury-bearing material accumulation in biomass accumulation areas, such as landfills, from batteries, electrical switches, thermometers, and fluorescent lights (Lindberg et al 2001). This will assist in determining appropriate abatement techniques for cleaning the work environment and environmental mitigation to determine waste stream components and risk assessment protocol. Determination of the by-products for personal protection equipment and personal exposure monitoring parameters are also part of this experimental work
Recommended from our members
Materials Evaluation Test Series (METS) 04, 05, and 06
The purpose of this work is to examine the environmental, safety, health and operational aspects of detonating a confined explosive test apparatus that has been designed to maximize the dynamics of impact on beryllium metal components for Contained Firing Facility (CFF) applications. A combination of experimental collection and evaluation methods were designed and implemented to provide an evaluation of immediately postdetonation by-products reflecting a potential worst-case scenario beryllium aerosolization explosive event. The collective Material Evaluation Test Series (METS) 04 - 06 provided explosive devices designed to scale for the dedicated METS firing tank that would provide a post-detonation internal environment comparable to the CFF. The experimental results provided appropriate information to develop operational parameters to be considered for conducting full-scale beryllium-containing experimental tests with similar designs within CFF and B801A. These operational procedures include the inclusion of chelating agents in pre-shot CFF cardboard containers with a minimum of 600 gallons content, an extended time period post-test before purging the CFF chamber, and an adaptation of approaches toward applications of the scrubber and HEPA systems during the post-shot sequence for an integrated environmental, safety, and health approach. In addition, re-entry and film retrieval procedures will be adapted, in line with abatement techniques for cleaning the chamber, that will be required for work inside a CFF that will contain an elevated concentration of spherical and highly aerosolizable beryllium particulate
- …