Health Physics

Reponen, Auvo ; Jantunen, Matti

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No Abstract available

Kathren, Ronald L.; McInroy, James F.

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The systemic deposition of 239+240Pu was determined by postmortem radiochemical analysis of the tissues from five whole-body donors to the United States Transuranium Registry (USTR). All were males with intakes typically occurring many years prior to death. The postmortem radiochemical results were compared with estimates of systemic deposition made with 13 different biokinetic models using urinary excretion data obtained during life. In general, estimates made with older biokinetic models were severalfold greater than those obtained from radiochemical analysis of the tissues. For all five cases, agreement within a factor of two with the tissue analysis results was obtained with two of the biokinetic models evaluated: the Langham power function model as modified by Leggett and Eckerman and the two compartment exponential model proposed in ICRP Publication Nos. I9 and 30.

Martz, Dowell E.; George, Joan L.; Langner, G. Harold

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The accuracy and precision of indoor 222Rn measurements obtained with the use of diffusion barrier charcoal canisters (DBCC) under actual field conditions were determined by comparing the integrated average of 26 successive 7-d exposures of DBCC in each of 16 occupied residences over a 6-mo period with simultaneous measurements using four types of commercially available alpha-track monitors (ATM) and one type of scintillation chamber continuous 222Rn monitor. The results suggest that properly calibrated DBCCs provide very good estimates of the integrated 222Rn concentrations in residential structures over the standard 1-wk exposure period despite the occurrence of large diurnal variations in the actual 222Rn concentrations. The results also suggest that a relatively small number of 1-wk DBCC measurements at selected times throughout the calendar year would provide estimates of the annual average indoor 222Rn concentrations that compare favorably with single long-term ATM measurements.

Kearfott, K. J.; Chesser, J. M.; Mitchell, H. E.; Coombs, M. A.

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Unusual reported dose equivalents due to high-energy photons for two individuals prompted the investigation of the effects of severe heating conditions expected in closed vehicles during southwestern summer months on commercial film dosimeters. A historical review of dosimetry records revealed several additional reported high-energy photon exposures for individuals using only beta-emitting radioisotopes during hot summer months. Between 20–100% of experimentally heated badges had apparent dose equivalents exceeding the minimal detectable dose equivalent that were not flagged as being heat damaged or having unusual exposure patterns by the dosimetry companies. Reported dose equivalents for these badges were as high as 2.1 mSv.

Wilson, John W.; Cucinotta, Francis A.; Hajnal, Ferenc

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A simple analytic formula for the nuclear fields formed by target fragmentation in tissue systems is derived using the continuous slowing down approximation (CSDA). The energy fluctuations in sensitive localized sites within the tissue system caused by these nuclear events are defined by microdosimetry. In that CSDA is used, the energy fluctuations exclude the role of secondary electrons. The relations also relate to the response of microdosimetric devices to nuclear fragmentation fields.

Stuchly, M. A.; Kozlowski, J. A.; Symons, S. ; Lecuyer, D. W.

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Radiofrequency electromagnetic fields can affect human health not only by direct interactions but indirectly through induction of charges on isolated or poorly grounded conductive (metallic) objects located in these fields. A person who touches such an object may perceive a tingling or prickling sensation or heat, or experience pain or electric shock. For sufficiently large objects, these phenomena can occur at field strengths that are relatively low and below the health protection limits based on direct interactions. We describe a method and circuitry developed to evaluate steady-state contact currents that may flow through a person touching conductive objects and give a summary of experimental tests performed. The method is simple and viable for field tests aimed at preventing pain, shock, and burn hazards in radiofrequency electromagnetic fields except those related to spark discharges. The method is applicable up to about 30 MHz.

Urabe, Itsumasa ; Kobayashi, Katsuhei ; Fujita, Yoshiaki ; Tsujimoto, Tadashi ; Guangchuan, Jin

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No Abstract available

Jaque, F. ; Cusso, F. ; de Career, I. Aguirre; Lifante, G. ; Calderon, T.

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No Abstract available

Collopy, Peter

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A multilevel assessment program can be integrated into normal operational requirements and used to identify and correct operational errors. Assessments are made during routine surveys by field technicians, monthly by the Radiation Safety Officer, and biennially by an independent radiological expert. These systematic assessments can prevent the occurrence of significant program problems and result in a decreased number of Nuclear Regulatory Commission citations.

Meager, William M.; Lucas, Robert M.; Daum, Keith A.; Sensintaffar, Edwin ; Poppell, Sam ; Feldt, Lisa ; Clarkin, Mike

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Three models of a-track detector (ATD) Rn monitors were exposed in Environmental Protection Agency (EPA) Rn chambers to obtain estimates of precision and bias for the National Residential Radon Survey (NRRS). Exposures in this study ranged from 37 to 740 Bq y m−3(1 to 20 pCi y L−1), plus blanks. These exposures correspond to the range expected in most U.S. residences. All detectors were purchased through a Rn mitigation firm to assure that the vendors did not give special attention to the ATDs used in this study. Ten ATDs of each model were studied at 12 exposures. The mean and standard deviation of the reported values for each model were calculated and compared with the continuously monitored chamber concentrations to determine the bias and precision at each exposure. Results of this analysis were discussed with the vendors, who took corrective actions. Changes in track counting procedures and calibrations improved detector performance. Readings of one detector were adjusted based on a regression of the monitored values on the reported values.