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Area Monitoring and Contingency Planning
Published in Martha J. Boss, Dennis W. Day, Air Sampling and Industrial Hygiene Engineering, 2020
An overriding principle of radiation protection philosophy is that all exposures must be maintained at ALARA levels. Thus, even if a given exposure to an individual is within regulatory limits, it may not be acceptable if the exposure could have been limited further by “reasonable” means.
Management of Monitoring Programs
Published in Kenneth L. Miller, of Radiation Protection Programs, 2020
Monitoring is often regarded as a regulatory requirement to demonstrate compliance with exposure limits. Approaching monitoring programs on this basis is too restrictive. Monitoring is not performed solely to detect problems nor to demonstrate compliance with exposure limits; rather, it is an essential tool for optimization. The current philosophy of radiation protection espoused by the International Commission of Radiation Protection1 is that all radiation exposures are accompanied by some level of risk and the benefits derived from the exposure are to be optimized. Monitoring data are central in the analysis of optimization. Risks, both real and potential, are brought into more tangible quantities that can be ranked and served as inputs to deductive decision-making processes.
Origin and Classification of Radiation
Published in Philip T. Underhill, Naturally Occurring Radioactive Material, 2018
Despite being the preferred unit of human dose for many years (and still in common usage on “Star Trek”), the rad is no longer used for measuring radiation dose to an organism because it does not indicate how much biological damage has actually occurred. A unit called the rem (Roentgen Equivalent Man) was developed to equate deposited energy to biological damage (biological dose equivalent). The rem and its S.I. equivalent, the sievert, are the units of choice for radiation protection.
Analysis of SAR reduction to human head with plasma photonic crystals shield using ICCG-SFDTD method
Published in Radiation Effects and Defects in Solids, 2021
Da-Jie Song, Yun Zhang, Jin Xie, Yu-Jie Liu, Hong-Wei Yang
MRI is considered a safe technology because it relies on the spatial encoding of atomic nuclei (mainly protons) position in a static magnetic field by irradiation with radio-frequency (RF) pulses as opposed to ionizing radiation (11). MRI systems are routinely used for clinical diagnosis and can produce high-quality images with relatively low static magnetic field strengths (12). However, ultra-high-field MRI systems are required in order to achieve enhanced signal-to-noise ratio in images and to improve resolution for spectroscopy applications in the future, challenges exist as significantly strong electric field and eddy currents can result in more RF energy deposits that potentially initiate tissue heating and cause other side effects, such as alterations in visual, auditory and neural functions (13). SAR (14) is the most frequently used parameter for monitoring and quantifying the power deposition to subjects in the electromagnetic environment. Strict exposure limits to SAR levels are imposed by the International Commission on Non-Ionizing Radiation Protection.
Study of epoxy shielding material with barium sulphate for development of radiation protection materials in low-dose diagnostic X-ray
Published in Radiation Effects and Defects in Solids, 2021
Nuttapong Danthanavat, Manus Mongkolsuk, Gunjanaporn Tochaikul, Soontaree Sriwongta, Atitaya Piyajaroenporn, Cholakorn Lithreungnam, Nutthapong Moonkum
Ionizing radiation is widely used in industry and medicine and can present a significant health hazard by causing microscopic damage to living tissue (1). In fact, the low-dose exposures might be able to induce DNA damage (2), and the dose–effect relationship could be hormetic or biphasic with beneficial effects at low doses and harmful effects at high doses (3). Fundamental to radiation protection is the avoidance or reduction of doses using the simple protective measures of time, distance and shielding (4).
Radiation Protection Design and Licensing for an Experimental Fusion Facility: The Italian and European Approaches
Published in Fusion Science and Technology, 2019
S. Sandri, G. M. Contessa, M. Guardati, M. Guarracino, R. Villari
The main technical aspects that authorities consider when giving a judgment on installation are related to the level of protection guaranteed to workers and to the population during normal and accident situations. All of the radiation protection principles are taken into account: justification, optimization, and dose limitation.