Respiratory protective device design using control system techniques

The feasibility of a control system analysis approach to provide a design base for respiratory protective devices is considered. A system design approach requires that all functions and components of the system be mathematically identified in a model of the RPD. The mathematical notations describe the operation of the components as closely as possible. The individual component mathematical descriptions are then combined to describe the complete RPD. Finally, analysis of the mathematical notation by control system theory is used to derive compensating component values that force the system to operate in a stable and predictable manner

Methods of Statistical Control for Groundwater Quality Indicators

The article describes the results of conducted groundwater quality control. Controlled quality indicators included the following microelements - barium, manganese, iron, mercury, iodine, chromium, strontium, etc. Quality control charts - X-bar chart and R chart - were built. For the upper and the lower threshold limits, maximum permissible concentration of components in water and the lower limit of their biologically significant concentration, respectively, were selected. The charts analysis has shown that the levels of microelements content in water at the area of study are stable. Most elements in the underground water are contained in concentrations, significant for human organisms consuming the water. For example, such elements as Ba, Mn, Fe have concentrations that exceed maximum permissible levels for drinking water

Addressing current knowledge gaps on radionuclide transfer to reptiles

Model intercomparison exercises have identified radionuclide transfer predictions as the greatest source of uncertainty in biota dose assessments. One wildlife group for which few transfer data exist is reptiles. Given that reptiles are an important, and often protected, component of many ecosystems and that assessments of radiation impact on ecosystems are becoming increasingly necessary due to the current nuclear renaissance, there is a need to further develop our current database on transfer to reptiles or find alternative approaches to estimate reptile transfer parameters. Three approaches that have the potential to increase the availability of parameters to predict radionuclide transfer to reptiles are the use of non-lethal sampling techniques, phylogenetic relationships and allometric relationships. Non-lethal sampling is an attractive long term option for deriving transfer parameters, but the derivation of phylogenetic and allometric relationships could provide ways of predicting transfer in the interim

Modelling the exposure of wildlife to radiation: key findings and activities of IAEA working groups

The International Atomic Energy Agency (IAEA) established the Biota Working Group (BWG) as part of its Environmental Modelling for Radiation Safety (EMRAS) programme in 2004 (http://www-ns.iaea.org/projects/emras/emras-biota-wg.htm). At that time both the IAEA and the International Commission on Radiological Protection (ICRP) were addressing environmental protection (i.e. protection of non-human biota or wildlife) within the on-going revisions to the Basic Safety Standards and Recommendations respectively. Furthermore, some countries (e.g. the USA, UK) were already conducting assessments in accordance with national guidelines. Consequently, a number of assessment frameworks/models had been or were being developed. The BWG was established recognising these developments and the need to improve Member State’s capabilities with respect to protection of the environment from ionizing radiation. The work of the BWG was continued within the IAEA’s EMRAS II programme by the Biota Modelling Group (http://wwwns. iaea.org/projects/emras/emras2/working-groups/working-group-four.asp)

Aquatic live animal radiotracing studies for ecotoxicological applications : addressing fundamental methodological deficiencies

The use of live animal gamma radioisotope tracer techniques in the field of ecotoxicology allows laboratory studies to accurately monitor contaminant biokinetics in real time for an individual organism. However, methods used in published studies for aquatic organisms are rarely described in sufficient detail to allow for study replication or an assessment of the errors associated with live animal radioanalysis to be identified. We evaluate the influence of some important methodological deficiencies through an overview of the literature on live aquatic animal radiotracer techniques and through the results obtained from our radiotracer studies on four aquatic invertebrate species. The main factors discussed are animal rinsing, radioanalysis and geometry corrections. We provide examples of three main techniques in live aquatic animal radiotracer studies to improve data quality control and demonstrate why each technique is crucial in interpreting the data from such studies. The animal rinsing technique is also relevant to non-radioisotope tracer studies, especially those involving nanoparticles. We present clear guidance on how to perform each technique and explain the importance of proper reporting of the validation of each technique for individual studies. In this paper we describe methods that are often used in lab-based radioecology studies but are rarely described in great detail. We hope that this paper will act as the basis for standard operating procedures for future radioecology studies to improve study replication and data quality control