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Engineering, administrative, and work practice controls have been recommended for many years to minimize exposure to nitrous oxide during dental procedures. To better understand the extent to which these exposure controls are used, the NIOSH Health and Safety Practices Survey of Healthcare Workers was conducted among members of professional practice organizations representing dentists, dental hygienists and dental assistants. The anonymous, modular, web-based survey was completed by 284 dental professionals in private practice who administered nitrous oxide to adult and/or pediatric patients in the seven days prior to the survey. Use of primary engineering controls (i.e., nasal scavenging mask and/or local exhaust ventilation (LEV) near the patient's mouth) was nearly universal, reported by 93% and 96% of respondents who administered to adult (A) and pediatric (P) patients, respectively. However, adherence to other recommended precautionary practices were lacking to varying degrees, and were essentially no different among those administering nitrous oxide to adult or pediatric patients. Examples of work practices which increase exposure risk, expressed as percent of respondents, included: not checking nitrous oxide equipment for leaks (41% A; 48% P); starting nitrous oxide gas flow before delivery mask or airway mask was applied to patient (13% A; 12% P); and not turning off nitrous oxide gas flow before turning off oxygen flow to the patient (8% A; 7% P). Absence of standard procedures to minimize worker exposure to nitrous oxide (13% of all respondents) and not being trained on safe handling and administration of nitrous oxide (3%) were examples of breaches of administrative controls which may also increase exposure risk. Successful management of nitrous oxide emissions should include properly fitted nasal scavenging masks, supplemental LEV (when nitrous oxide levels cannot be adequately controlled using nasal masks alone), adequate general ventilation, regular inspection of nitrous oxide delivery and scavenging equipment for leaks, availability of standard procedures to minimize exposure, periodic training, ambient air and exposure monitoring, and medical surveillance.

Prevention is paramount and the development of standard operating procedures modeled after evidence-based infection control measures designed to prevent or limit the spread of infection in dentistry are key to the safety of both workers and patients alike. Equally important is the training and education of dental health-care providers about these procedures and their use, monitoring for compliance to see where there is need for improvements, and implementing measures for change to prevent or minimize future noncompliance. Unfortunately, noncompliance with safety measures will always be an issue for some, and despite the use of safety measures, accidents will still occur and occupational exposures will occur. These must be managed according to the various national guidelines. This includes prompt referral to a qualified health-care provider for evaluation of the exposed individual and, where warranted, postexposure prophylaxis (PEP) and appropriate monitoring and follow-up. All of these policies should be clearly written in the office’s Exposure Control Plan. Therefore, it is of the upmost importance for all institutions and private offices to have an exposure control plan (ECP) with clear policies and procedures designed to help dental health-care providers, not only to prevent the spread of infection, but also to know how to manage an occupational exposure incident. This chapter will review the principles of Postexposure Monitoring and Prophylaxis and what goes into an Exposure Control Plan.

In this paper, we propose a noise-aware exposure control algorithm for robust robot vision. Our method aims to capture the best-exposed image which can boost the performance of various computer vision and robotics tasks. For this purpose, we carefully design an image quality metric which captures complementary quality attributes and ensures light-weight computation. Specifically, our metric consists of a combination of image gradient, entropy, and noise metrics. The synergy of these measures allows preserving sharp edge and rich texture in the image while maintaining a low noise level. Using this novel metric, we propose a real-time and fully automatic exposure and gain control technique based on the Nelder-Mead method. To illustrate the effectiveness of our technique, a large set of experimental results demonstrates higher qualitative and quantitative performances when compared with conventional approaches., Comment: 8 pages,6 figures, accepted in IROS2019

OBJECTIVE The aim of this study was to examine military occupational specialty (MOS) codes to identify those at risk from inhalation exposures during Southwest Asia deployment. METHODS Exposure intensity to diesel exhaust, sandstorms, burn pit smoke, combat dust, and occupational vapors/dusts/gases/fumes (VDGF) were scored for all Army/Marine MOS codes by an expert panel. Based on MOS code, panel-rated exposure scores were compared with questionnaire data from military personnel with postdeployment respiratory illnesses. RESULTS All exposures except VDGF were rated higher (range P

Background Total paper dust exposure has been associated with respiratory problems among workers in the soft tissue paper industry. However, a comprehensive job exposure matrix (JEM) has not been developed for application to this industry. Our study was intended to address this need and to support further studies of mortality and morbidity in a cohort of Swedish workers from this industry. Methods We evaluated four participating soft tissue paper mills in Sweden. We combined information on process and equipment status from the mills with knowledge of the mills obtained through research efforts and paper dust measurements made at all four mills to develop a semi-quantitative JEM with seven dust exposure levels. The JEM was targeted at workers enrolled into a soft tissue paper mill cohort and working any time between 1960 and 2009. Results The JEM includes a total of 14 421 cells, with each cell corresponding to the exposure for a job title, department, or work location for a one-year period. Exposure levels in the JEM were estimated to decline at three of the four mills from 1971 to 2009, but overexposures (ie, exceedances of the relevant occupational exposure limits) remained common at the end of the period. Conclusions The JEM results highlight the need for ongoing exposure control efforts in the soft tissue paper industry, and will inform ongoing epidemiological studies of the health effects of exposure to paper dust in Sweden. It is freely available for use by other researchers.

The current endoscope design is not ergonomic. There is a high prevalence of endoscopy-related injury reported in the literature, and studies have demonstrated high-risk biomechanical exposures during the performance of routine colonoscopy. Endoscopy ergonomics focuses on understanding the endoscopist's interaction with the endoscope and the endoscopy unit and re-designing these tasks to minimize the risk of endoscopy-related injury. The discussion to date has focused on what the endoscopist can do to minimize his or her risk of injury. It is imperative that we re-frame that discussion because the implication that physicians are responsible for implementing personal or workplace interventions places an undue burden on physicians and will be the least effective exposure control method. Endoscope companies need to consider the endoscopist in their design process. As a profession, we need to collectively advocate for endoscopist safety. We offer a perspective on how ergonomic endoscopy can become a realistic and achievable goal.

Workers are increasingly exposed to nanoparticles, mostly via inhalation. Respiratory protection is recommended as an additional control measure. Particulate respirators are certified for protection against micro-sized particles, where a most penetrating particle size (MPPS) of 100–400 nm is assumed. Commonly used N95 respirators are certified by the National Institute for Occupational Safety and Health after passing a 95% collection efficiency test. Electret media used in respirators have been demonstrated to be shifting the MPPS to a nanosized region. Experimental studies have therefore been conducted to assess N95 respirator penetration specifically by nanoparticles. This systematic review and meta-analysis was aimed at systematically reviewing these studies and meta-analysing the mean penetration percentage (PP). The review was conducted following a Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Fourteen studies were selected to be reviewed qualitatively, while 13 of these with 29 data points were included in the meta-analysis. Sensitivity analysis was performed based on a respirator mounting protocol, while subgroup analysis was done for aerosol dispersity and repeated for the respirator mounting protocol. The size range of particles used across the reviewed studies was 1 nm–10 μm. The MPPS for all studies was in the nanosized particle range, with the lowest at approximately 39 nm. The estimated mean PP was between 1 and 6%, exceeding the 5% guideline threshold for four of the studies. All the meta-analysed mean PPs were however below the 5% guideline. This means that the N95 respirators may be effective for nanoparticles in workplaces, but subject to factors including respirator characteristics and particle dispersity.

BACKGROUND Cyanogen is a toxic flammable gas used as a fumigant in numerous industries. Occupational exposure to cyanogen can occur during its production and use. The most serious human health risk from exposure to cyanogen is via the respiratory system. However, there is also potential for skin exposure in many workplace situations. The extent of skin absorption under occupational exposure scenarios has not been directly assessed. Understanding skin uptake potential may inform risk assessment and exposure control measures. RESULTS We describe an in vitro experimental system using human epidermis and dynamic atmosphere exposure to cyanogen to mimic potential workplace exposures. The influence of clothing and ventilation on skin permeation outcomes were also assessed. No evidence of transdermal permeation was found at 100 or 1000 ppm exposures, while permeation of 0.99 ± 0.38 μg cm-2 was observed after 60 min exposure to 10 000 ppm. Fabric on skin and skin ventilation had no additional influence on transdermal permeation compared with naked skin, but fabric provided a reservoir for potential secondary exposures. CONCLUSION Results show dermal uptake following cyanogen exposure is possible, but only at very high atmospheric concentrations (10 000 ppm after >15 min exposure). Importantly, this could have implications for fumigant applicators who may only be wearing personal respiratory protection. These empirical data may be used in conjunction with other relevant toxicological information in determining whether a Skin Notation is warranted for Workplace Exposure Standard setting. © 2019 Society of Chemical Industry.

Drilling large holes (e.g., 10-20 mm diameter) into concrete for structural upgrades to buildings, highways, bridges, and airport runways can produce concentrations of respirable silica dust well above the ACGIH

This work describes a new approach to automatic dose rate control (ADRC) for dynamic x-ray imaging, utilizing a spatial frequency weighted signal difference to noise ratio (SDNR(u)). Three aspects of ADRC programming using SDNR(u), which contains information on the target material, velocity and size, were examined. First, whether SDNR(u) can be held constant at the requested level over some patient thickness range for five materials relevant to interventional imaging (iron, gadolinium, platinum, bismuth, and tantalum). Second, the efficiency of the new ADRC was compared to the current settings using a figure of merit (FOM), defined as SDNR(u)2/reference air kerma rate for iron and platinum, over a range of simulated patient thicknesses. Third, the ability of the new ADRC to optimize exposure parameters for iron, iodine, gadolinium, tantalum, platinum and bismuth was examined. A phantom of 20 mm PMMA and 2 mm Al sheets was used to simulate patient equivalent thicknesses between 25 mm to 375 mm. The relevant metal foil targets were placed at the phantom centre and imaged on a Siemens Artis Q cardio-angiography system. SDNR(u) and reference air kerma were measured, along with the FOM for the relevant conditions. The optimal exposure factor study was made for patient equivalent thicknesses of 100 mm, 200 mm and 300 mm. The new ADRC regulation held SDNR(u) constant versus phantom thickness within 5%, for the five materials studied. FOM increase compared to the current regulation used on the Artis Q ranged between 18% and 296% (averaged over all thicknesses), and depended on acquisition mode and material. Material optimization via the new ADRC increased FOM by 68%, 165%, 164% and 32% for gadolinium, tantalum, platinum and bismuth respectively, corresponding to potential dose savings of 40%, 62%, 62% and 24% for the same target SDNR(u). An SDNR(u) driven approach to the ADRC logic of dynamic imaging systems is a viable alternative to current programming, with a resulting improvement in imaging efficiency and corresponding dose reduction. ispartof: PHYSICS IN MEDICINE AND BIOLOGY vol:64 issue:4 ispartof: location:England status: published

With the increasing demand for green printing and environmental protection, the application of flexographic printing is ever-growing. The purpose of this paper is to study the possibility of the standardization for the quality of flexographic platemaking, and provide basic data and reference for the platemaking process control related standard. Experiments on back exposure control and analysis of printing forme quality through four mainly used brand plates with two different thickness were conducted, the relationships between the relief height and the back exposure time, and the related imaging quality of flexographic printing forme, including small dots, fine lines, small characters, tone reproduction were studied. The results show that it is possible to specify a set of standardized imaging quality indexes for flexographic printing forme to control platemaking process which are suitable for diverse platemaking technology and plates.

The current study compares the progressive-restricted standard error (PR-SE) exposure control method with the Sympson-Hetter, randomesque, and no exposure control (maximum information) procedures using the generalized partial credit model with fixed- and variable-length CATs and two item pools. The PR-SE method administered the entire item pool for all conditions; whereas the Sympson-Hetter and randomesque procedures did not administer 27%–28% and 14%, respectively, of item pool 1 and about 45%–50% and 27%–29% of item pool 2, respectively, of the items that were not administered. PR-SE also resulted in the smallest amount of mean item overlap averaged across replications. These results were obtained with similar measurement precision compared to the other methods while improving on the utilization of the item pools, except for very low theta levels (less than −2) for item pool 2, where a mismatch with the trait distribution occurs.

This paper presents a method that can determine the optimal exposure time for high-quality three-dimensional (3D) shape measurement with digital fringe projection technique. The proposed method only requires capture fringe image(s) with one exposure time to automatically determine the global optimal exposure time for high-quality 3D shape measurement; and we further propose to automatically achieve high-dynamic range (HDR) 3D shape measurement by capture image(s) with the optimized global single exposure. Experimental results demonstrated the proposed method can successful work on a static complex scene and can also be applicable for real-time applications.

Computer adaptive testing (CAT) has been shown to shorten the test length and increase the precision of latent trait estimates. Oftentimes, test takers are asked to respond to several items that are related to the same passage. The purpose of this study is to explore three CAT item selection techniques for items of the same passages and to provide recommendations and guidance for item selection methods that yield better latent trait estimates. Using simulation, the study compared three models in CAT item selection with passages: (a) the testlet-effect model (T); (b) the passage model (P); and (c) the unidimensional IRT model (U). For the T model, the bifactor model with testlet-effect or constrained multidimensional IRT model was applied. For each of the three models, three procedures were applied: (a) no item exposure control; (b) item exposure control of rate 0.2 ; and (c) item exposure control of rate 1. It was found that the testlet-effect model performed better than passage or unidimensional models. The P and U models tended to overestimate the precision of the theta or latent trait estimates.

Under- and oversaturation can cause severe image degradation in many vision-based robotic applications. To control camera exposure in dynamic lighting conditions, we introduce a novel metric for image information measure. Measuring an image gradient is typical when evaluating its level of image detail. However, emphasizing more informative pixels substantially improves the measure within an image. By using this entropy weighted image gradient, we introduce an optimal exposure value for vision-based approaches. Using this newly invented metric, we also propose an effective exposure control scheme that covers a wide range of light conditions. When evaluating the function (e.g., image frame grab) is expensive, the next best estimation needs to be carefully considered. Through Bayesian optimization, the algorithm can estimate the optimal exposure value with minimal cost. We validated the proposed image information measure and exposure control scheme via a series of thorough experiments using various exposure conditions.

Introduction Increasingly, models and tools are used by occupational hygienists, risk assessors and risk managers for estimating exposure to and risk from chemical agents in the workplace. These range from simple, screening tools (tier 1 tools) that provide conservative exposure estimate, to more complex higher tier exposure models. In Europe, tools such as ECETOC TRA, STOFFENMANAGER and ART have been developed and are used predominantly for risk assessment as part of the REACH regulations. Furthermore, tools for estimating exposure to nano-sized particles have been developed (e.g. NANOSAFER, Stoffenmanager-NANO). In recent years, several studies have been carried out to test the performance of these tools. Methods Several studies were carried out to determine the performance of the exposure tools for chemical agents and nano-materials, including comparison with measurement data as well as inter-user comparisons. Results The comparison of tool estimates with measurement data suggested that the tier 1 tools appear to be conservative, although this varied between tools and type of exposure. Correlations between the measurement results and tool predictions also varied with tool and exposure type. Furthermore, a wide range of exposure estimates were observed when different users were asked to apply the same tools to the same scenario conditions. Conclusion Models to estimate exposure and risk are essential elements of the toolbox of occupational hygienists and risk assessors and managers. However, there is increasing evidence that performance varies between tools, type of exposure and scenario conditions. More importantly, users appear to struggle to apply the tools consistently, leading to wide ranges in estimated exposures. There is an urgent need for the development and implementation of generic quality control procedures for use of exposure tools, to reduce the large uncertainties when applying these tools, both to prevent workers from being excessively exposed and unnecessarily implementation of stringent exposure control measures.

Cognitive diagnostic computerized adaptive testing (CD-CAT) not only provides useful cognitive diagnostic information measured in psychological or educational assessments, but also obtains great efficiency brought by computerized adaptive testing. At present, there are only a limited numbers of previous studies examining how to optimally construct cognitive diagnostic tests. The cognitive diagnostic discrimination index (CDI) and attribute-level discrimination index (ADI) have been proposed for item selection in cognitive diagnostic tests. Zheng and Chang (Appl Psychol Measure 40:608–624, 2016) proposed the modified version of these two indices, an extension of the Kullback-Leibler (KL) and posterior-weighted KL (PWKL) methods, and suggested that they could be integrated with the constraint management procedure for item selection in CD-CAT. However, the constraint management procedure hasn’t been investigated in CD-CAT yet. Therefore, the aim of this study is two fold (a) to integrate the indices with the constraint management procedure for item selection, and (b) to investigate the efficiency of these item selection methods in CA-CAT. It was found that the constraint-weighted indices performed much better than those without constraint-weighted procedure in terms of constraint management and exposure control while maintaining similar measurement precision.

This Month Contraindications to lipid emulsion therapy Key words: lipid emulsion therapy, local anesthetic systemic toxicity, LAST, local anesthetics, toxicity. Integrating a music program into the perioperative setting Key words: music, music therapy, pain, anxiety. Exposure control plans in the OR Key words: exposure control plan, Occupational Safety and Health Administration, OSHA, sharps safety, exposure, sharps selection and evaluation.

Preliminary researches indicate that in some cases nano-particulate matter may be more toxic than other forms of the same or similar material. The term prevention comprises all measures directed at minimizing the risk associated with a specific exposure, the early detection through medical surveillance of adverse health effects resulting from such an exposure and the treatment of diseases. Application of the classical tools of occupational medicine and industrial hygiene are hampered by the lack of consensus guidelines for medical monitoring, exposure assessment, and exposure control. So, the problem of occupational exposure to nanoparticles (NPs) has raised many questions which remain unanswered till today. This review aims at discussing some general features of ENMs (Engineered nano-materials), how a worker might be exposed to ENMs, some potential health effects, and approaches to minimize exposure and toxicity. .

Ever growing populations in cities are associated with a major increase in road vehicles and air pollution. The overall high levels of urban air pollution have been shown to be of a significant risk to city dwellers. However, the impacts of very high but temporally and spatially restricted pollution, and thus exposure, are still poorly understood. Conventional approaches to air quality monitoring are based on networks of static and sparse measurement stations. However, these are prohibitively expensive to capture tempo-spatial heterogeneity and identify pollution hotspots, which is required for the development of robust real-time strategies for exposure control. Current progress in developing low-cost micro-scale sensing technology is radically changing the conventional approach to allow real-time information in a capillary form. But the question remains whether there is value in the less accurate data they generate. This article illustrates the drivers behind current rises in the use of low-cost sensors for air pollution management in cities, while addressing the major challenges for their effective implementation. Keywords: Air pollution, Exposure assessment, Health risks, Cities and megacities, Sensors

The proliferation of nano-enabled products (NEPs) renders human exposure to engineered nanomaterials (ENMs) inevitable. Over the last decade, the risk assessment paradigm for nanomaterials focused primarily on potential adverse effect of pristine, as-prepared ENMs. However, the physicochemical properties of ENMs may be drastically altered across their life-cycle (LC), especially when they are embedded in various NEP matrices. Of a particular interest is the end-of-life scenario by thermal decomposition. The main objective of the current study is to develop a standardized, versatile and reproducible methodology that allows for the systematic physicochemical and toxicological characterization of the NEP thermal decomposition. The developed methodology was tested for an industry-relevant NEP in order to verify its versatility for such LC investigations. Results are indicative of potential environmental health risks associated with waste from specific NEP families and prompt for the development of safer-by-design approaches and exposure control strategies.

Our goal was to define a pediatric head CT protocol able to provide images of diagnostic quality, using the least amount of radiation, in children

Control banding (CB) has been widely recommended for the selection of exposure controls for engineered nanomaterials (ENMs) in the absence of ENM-specific occupational exposure limits (OELs). Several ENM-specific CB strategies have been developed but have not been systematically evaluated. In this article, we identify the data inputs and compare the guidance provided by eight CB tools, evaluated on six ENMs, and assuming a constant handling/use scenario. The ENMs evaluated include nanoscale silica, titanium dioxide, silver, carbon nanotubes, graphene, and cellulose. Several of the tools recommended the highest level of exposure control for each of the ENMs in the evaluation, which was driven largely by the hazard banding. Dustiness was a factor in determining the exposure band in many tools, although most tools did not provide explicit guidance on how to classify the dustiness (high, medium, low), and published data are limited on this topic. The CB tools that recommended more diverse control options based on ENM hazard and dustiness data appear to be better equipped to utilize the available information, although further validation is needed by comparison to exposure measurements and OELs for a variety of ENMs. In all CB tools, local exhaust ventilation was recommended at a minimum to control exposures to ENMs in the workplace. Generally, the same or more stringent control levels were recommended by these tools compared with the OELs proposed for these ENMs, suggesting that these CB tools would generally provide prudent exposure control guidance, including when data are limited.

Exposure to asbestos in occupational circumstances has decreased considerably in most developed countries over the last three decades, with improved exposure control and monitoring in most work situations and the prohibition on the use of asbestos in most occupational circumstances. Unfortunately, occupational exposures do still occur through renovation, repair and demolition of buildings, either with asbestos removal being a specific focus of the work or asbestos exposure being incidental to the main purpose of the work. Focus has also increased in recent years on exposure in non-occupational circumstances to in-situ asbestos, particularly through ”Do-It-Yourself” (DIY) home renovations. These occupational and non-occupational circumstances are the so-called ”third wave” of exposure to asbestos. Despite considerable efforts in terms of occupational education and training, and broader publicity, there appears to be a lack of awareness by many workers of the potential for asbestos exposure and the circumstances in which such exposures can be expected. This leads to potential exposures not being appropriately controlled and probably to workers being inadvertently exposed or exposed at levels higher than is necessary or considered acceptable. Although many of the high-risk situations are known or can be reasonably anticipated, there is a lack of information on the frequency and levels of exposures associated with many of these third wave exposure situations, making it difficult to develop appropriate guidance regarding preventing and controlling the exposures. This presentation will consider these issues as part of the overall symposium on ”In situ asbestos and the risks of exposure for workers ”.

We develop a methodology for index tracking and risk exposure control using financial derivatives. Under a continuous-time diffusion framework for price evolution, we present a pathwise approach to construct dynamic portfolios of derivatives in order to gain exposure to an index and/or market factors that may be not directly tradable. Among our results, we establish a general tracking condition that relates the portfolio drift to the desired exposure coefficients under any given model. We also derive a slippage process that reveals how the portfolio return deviates from the targeted return. In our multi-factor setting, the portfolio's realized slippage depends not only on the realized variance of the index, but also the realized covariance among the index and factors. We implement our trading strategies under a number of models, and compare the tracking strategies and performances when using different derivatives, such as futures and options.

We propose an active exposure control method to improve the robustness of visual odometry in HDR (high dynamic range) environments. Our method evaluates the proper exposure time by maximizing a robust gradient-based image quality metric. The optimization is achieved by exploiting the photometric response function of the camera. Our exposure control method is evaluated in different real world environments and outperforms the built-in auto-exposure function of the camera. To validate the benefit of our approach, we adapt a state-of-the-art visual odometry pipeline (SVO) to work with varying exposure time and demonstrate improved performance using our exposure control method in challenging HDR environments.

Background Closed system transfer device (CSTD) mechanically prohibits the transfer of environmental contaminants into the system and the escape of hazardous drug or vapour concentrations outside the system. However, various CSTDs are not equally effective. Purpose We evaluated the impact of current and new CSTD systems on exposure of healthcare personnel to chemotherapy agents and how the new CSTD would fit into our workflow. Material and methods To ensure safety and compliance of a new CSTD system, our first step was a hands-on product demonstration to evaluate the new technology. The review included ease of use of the system and review of all system components. The second step was to take surface wipe samples. We used CytoWipe kits from Exposure Control. We carried out two compounding trials (existing CSTD and new CSTD), each lasting 3 weeks. Sampling locations in pharmacy included: Scale in the laminar flow cabinet (LAF) LAF surface. Counter with prepared chemotherapy. Floor in front of the LAF. Pass through surface. Vials. Baseline contamination was determined with initial cleaning with NaOH and HCl. During the trials, cleaning was performed per facility protocol (detergent, IPA and biocid B or C (KlerWipe) daily and 0.05 M NaOH weekly). Monitored drugs were cyclophosphamide and 5-fluorouracil. Exposure Control analysed cyclophosphamide using a GC-MSMS method and 5-fluorouracil using a HPLC system with UV detection. Results We found that while both systems were easy to use, the new CSTD system provided enhanced safety by ensuring compliance without an option to bypass the system. The limited surface wipe sample analysis showed that cleaning and workflow were important factors in minimising exposure of healthcare personnel to chemotherapy agents. With the current CSTD system, cyclophosphamide contamination was found on surfaces 1, 2 and 4, and barely detectable on 5 and 6. No contamination with 5-fluorouracil was found. With the new CSTD, cyclophosphamide contamination was found only on surfaces 4 and 6 that had little or no correlation with compounding. No contamination with 5-fluorouracil was found. Conclusion The study showed that the new CSTD system ensures compliance, fits into our workflow and can help minimise exposure of healthcare personnel to chemotherapy agents. No conflict of interest

Biological monitoring is a useful tool to assess occupational and environmental exposure following a wide range of chemical incidents. Guidance values are available from international organisations to help interpret the result of biological monitoring. In addition, guidance values based on the 90th percentile of biological monitoring data obtained under conditions of good exposure control may help identify lapses in control and the need for remedial action to improve controls and reduce risk. In all cases interpretation of biomonitoring results following incidents needs care and in particular reference to the time of sample collection and basis of the guidance values. Biomonitoring guidance values specifically derived for chemical incident scenarios are not available but would be of great help to interpret biological monitoring results.

Automatic exposure control (AEC) is particularly well-suited for pediatric CT scanning. However the importance of the localizer scan portion of exams that relies on AEC is frequently underestimated. This paper explains in detail several crucial aspects of the localizer and their effect on the subsequent cross-sectional (axial or helical) image acquisition. The paper also covers general suggestions regarding AEC influence on the cross-sectional images. AEC systems on CT scanners are becoming more complex; using them effectively in the setting of pediatric CT requires careful selection of scan parameters.

a-Stratified computerized adaptive testing with b-blocking (AST), as an alternative to the widely used maximum Fisher information (MFI) item selection method, can effectively balance item pool usage while providing accurate latent trait estimates in computerized adaptive testing (CAT). However, previous comparisons of these methods have treated item parameter estimates as if they are the true population parameter values. Consequently, capitalization on chance may occur. In this article, we examined the performance of the AST method under more realistic conditions where item parameter estimates instead of true parameter values are used in the CAT. Its performance was compared against that of the MFI method when the latter is used in conjunction with Sympson–Hetter or randomesque exposure control. Results indicate that the MFI method, even when combined with exposure control, is susceptible to capitalization on chance. This is particularly true when the calibration sample size is small. On the other hand, AST is more robust to capitalization on chance. Consistent with previous investigations using true item parameter values, AST yields much more balanced item pool usage, with a small loss in the precision of latent trait estimates. The loss is negligible when the test is as long as 40 items.

The intent of this research was to find an item selection procedure in the multidimensional computer adaptive testing (CAT) framework that yielded higher precision for both the domain and composite abilities, had a higher usage of the item pool, and controlled the exposure rate. Five multidimensional CAT item selection procedures (minimum angle; volume; minimum error variance of the linear combination; minimum error variance of the composite score with optimized weight; and Kullback-Leibler information) were studied and compared with two methods for item exposure control (the Sympson-Hetter procedure and the fixed-rate procedure, the latter simply refers to putting a limit on the item exposure rate) using simulated data. The maximum priority index method was used for the content constraints. Results showed that the Sympson-Hetter procedure yielded better precision than the fixed-rate procedure but had much lower item pool usage and took more time. The five item selection procedures performed similarly under Sympson-Hetter. For the fixed-rate procedure, there was a trade-off between the precision of the ability estimates and the item pool usage: the five procedures had different patterns. It was found that (1) Kullback-Leibler had better precision but lower item pool usage; (2) minimum angle and volume had balanced precision and item pool usage; and (3) the two methods minimizing the error variance had the best item pool usage and comparable overall score recovery but less precision for certain domains. The priority index for content constraints and item exposure was implemented successfully.