Although a far cry from their counterparts of the 1970s, solar heating systems still present a significant up-front expense and can be less than aesthetically pleasing. Both cost and design improve as owners move toward green building and as architects incorporate solar components into more projects. This article presents the basics of solar-powered hot water heaters, which differ from traditional water heaters primarily in their power source. Major components include solar collector(s), circulation systems, storage tanks, a backup heating system, and control system. Direct systems (open loop) circulate domestic water between collectors and storage tanks. Direct systems can be downdrain or recirculating. Indirect systems (closed loop) circulate liquid (water, glycol) as a heating medium. Depending on their components, indirect systems can be more expensive and require more maintenance, but also have a number of advantages. Web-based resources are presented, along with a checklist including design criteria, types of systems, installation considerations, and mounting systems.
In 1989 the then Soviet government requested that the International Atomic Energy Agency (IAEA) assess the steps it took to protect the health of villagers in areas surrounding the site of the 1986 Chernobyl nuclear power plant accident. The International Chernobyl Project (ICP) performed the assessment. “Task 4” of the ICP studied sample populations from three Soviet republics. Teams of physicians from several nations visited seven “control” (uncontaminated) and six “contaminated” villages to obtain in-depth medical histories on and to perform extensive physical examinations of over 1300 persons. No adverse health effects directly attributable to radiation were found by Task 4. Many of the villagers demonstrated increased stress and anxiety related to the accident, but no significant differences were seen between residents of the contaminated and the control villages. However, a high incidence of hypertension, poor dental health, and obesity in the population samples from all the villages did exist. Although it was too early to see increases in leukemia and solid tumors in the populations examined, the authors expect that there will be increases in the incidence of both these types of cancers over the next several decades.
The objective of this Report is to review the current state-of-knowledge of uncertainties in internal dose assessments, including uncertainties in the measurements that are used to perform these assessments. In a previously published report (NCRP, 2007), the current state-of-knowledge of uncertainties in external radiation measurements and dosimetry was reviewed. The scope of this Report is limited to internal radiation exposure. It is intended to be used primarily by radiation dosimetrists, including health physicists, radiation protection professionals, and medical physicists who need to evaluate of the uncertainties in estimates of absorbed doses. The scope of application ranges from the improvement of routine dosimetry procedures to the reconstruction of individual doses in epidemiological studies to treatment planning for therapeutic nuclear medicine. Sections 1 to 4 are descriptive in nature and do not present a high level of technical difficulty and so may provide useful knowledge to health physicists, radiation protection professionals, and medical physicists who are involved in the assessment of doses from internal sources of radiation. Sections 5 to 10 are more technical and address issues of interest to health physicists involved in the assessment of uncertainties. The appendices, in which details of various methods and models are presented, are meant to be read by those scientists interested in a particular issue.
This book provides a thorough examination of the basic theory and principles behind eddy current testing.Contents: electrical theory; electromagnetism; inductive reactance and impedance; eddy current test principles; coils, instruments and standards; and impedance-plane response.
Author(s): Hagemaier, Donald J.
2. DESIGN AND EVALUATION OF SECURITY MEASURES
2.1. General approach
2.2. Basic security considerations
2.3. Security considerations for transport
2.5. Determination of security measures
3. ESTABLISHING SECURITY LEVELS FOR RADIOACTIVE MATERIAL IN TRANSPORT
4. GUIDANCE FOR SECURITY MEASURES IN THE TRANSPORT OF RADIOACTIVE MATERIAL
4.1. Prudent management practices
4.2. Basic security level
4.3. Enhanced security level
4.4. Additional security measures
4.5. International shipment
Radiation dose reconstruction is the retrospective assessment of dose to identifiable or representative individuals or populations by any means. In this Report, the scope of dose reconstruction includes estimates of absorbed dose to individual organs or tissues for specified exposure situations in support of epidemiological studies or compensation programs, to guide interventions in accidental or malevolent exposures, or for individual or public information. For the purpose of this Report, dose reconstruction excludes demonstration of compliance with regulatory criteria for workers or members of the public, and projections of dose from future or prospective exposures. There are many different applications of dose reconstruction as defined here, many potential approaches, and a great deal of scientific and public interest in the results.
This Report illustrates the breadth of the field, and emphasizes that all dose-reconstruction projects, while unique, incorporate a few basic elements, which are described and illustrated with many examples (case studies). Each case study is intended to demonstrate how specific limitations associated with the case study were overcome.
2. Basic Elements of Dose Reconstruction
3. Methodologic Issues in Performing Dose Reconstructions
4. Radiation Dose Estimation
5. Assessment of Uncertainties in Dose Reconstruction
6. Dose Reconstruction for Medical Exposures
7. Dose Reconstruction for Occupational Exposures
8. Dose Reconstruction for Environmental Exposures
9. Dose Reconstruction for Accidents and Incidents
Previously published by the Nuclear Regulatory Commission, this new edition is now being published by ASNT. Includes updated and revised information on X-ray safety, current regulations, current radiation units and quantities and new photographs. The book is ideal for companies who need to meet the NRC requirements for training radiographers.
Author(s): McGuire, Steven A.; Peabody, Carol A.; Leeman, Cynthia M. (ed.)
This study is the third worldwide study of gas and oil pipeline operations and gas distribution utilities (LDCs).
This new series will provide an in-depth appraisal of the central and remote site hardware, applications software, and communications services that oil and gas pipeline operations and gas distribution utilities will be requesting during their next round of procurements for SCADA systems.
The research study results in a comprehensive and informative series of reports on control systems usage patterns and plans of pipeline operations and gas distribution utilities worldwide. The research program will assess the market sizes and will contain projections on a world-region basis, for the next several years. A separate report profiling more than 50 suppliers of oil/gas pipeline SCADA-related systems, software and services will also be
Volume 1-Global Summary of Research Findings
Volume 2-Market Analysis/Forecast
Volume 3-Supplier Profiles
Fires doors are subjected to standard fire tests as a means of evaluating fire resistance. In this study, the thermal and mechanical response of steel double fire doors exposed to high temperatures was modeled using finite element software. The model included the necessary complexity of the product and test setup along with the temperature dependency of the constituent materials. For the thermal solution, a transient analysis was carried out while for the mechanical solution, it was found that a nonlinear steady state analysis was sufficient to capture the qualitative behavior of the fire doors seen during the test. The challenges of validating a numerical model with the limited data available from the standard fire test are described.