Evaluation of internal contamination levels after a radiological dispersal device incident using portal monitors

Abstract

Following a radioactive dispersal device (RDD) incident, it may be necessary to evaluate the internal contamination levels of a large number of potentially affected individuals to determine if immediate medical follow-up is necessary. Since the current laboratory capacity to screen for internal contamination is limited, rapid field screening methods can be useful in prioritising individuals. This study evaluated the suitability of a radiation portal monitor for such screening. A model of the portal monitor was created for use with models of six anthropomorphic phantoms in Monte Carlo N-Particle Transport Code Version 5 (MCNP) X-5 Monte Carlo Team (MCNP-A General Monte Carlo N-Particle Transport Code Version 5. LA-CP-03-0245. Vol. 2. Los Alamos National Laboratory, 2004.). The count rates of the portal monitor were simulated for inhalation and ingestion of likely radionuclides from an RDD for each of the phantoms. The time-dependant organ concentrations of the radionuclides were determined using Dose and Risk Calculation Software Eckerman, Leggett, Cristy, Nelson, Ryman, Sjoreen and Ward (Dose and Risk Calculation Software Ver. 8.4. ORNL/TM-2001/190. Oak Ridge National Laboratory, 2006.). Portal monitor count rates corresponding to a committed effective dose E(50) of 10 mSv are reported.

Simulation of Counting Efficiencies of Portable NaI Detector for Rapid Screening of Internal Exposure in Radiation Emergencies

“…과거 발생한 체르노빌 원전사고와 후쿠시 마 원전사고에서도 소아를 포함한 일반인의 내부피폭이 발생하였으며 관련 전문기관에서 내부피폭 측정 및 평가 를 수행한 바 있다 [1][2][3]. 그 외에도 방사능확산장치 (radiological dispersal device, RDD)를 이용한 방사능테 러 발생시에도 일반인의 내부피폭이 발생할 수 있으며 미국과 유럽에서는 이에 대비한 신속 내부피폭 검사방법 및 절차에 대한 연구를 진행 중에 있다 [4][5][6]. 방사능확산 장치의 경우 일반 산업체에서 널리 사용되는 감마선 방 출핵종이 상대적으로 쉽게 사용될 수 있으며 대표적인 핵종으로는 Cs, Co, Ir 등이 있다 [4][5][6].…”

Use of Transportable Radiation Detection Instruments to Assess Internal Contamination from Intakes of Radionuclides Part II

“…Palmer et al (2012) used MCNP5 and biokinetic models to simulate the response of the Transportable Portal Monitor Model TPM-903B (manufactured by Rapiscan Systems, Longmont, CO, USA, and distributed by Thermo Fisher Scientific Inc., Franklin, MA, USA) to inhaled and ingested intakes of 60 Co, 131 I, 137 Cs, and 192 Ir by reference and adipose adult males and adult females, a postmenopausal adipose female, and a 10-y-old child. The adults were represented by stylized anthropomorphic phantoms based on the reference male phantom developed at ORNL, with additions of adipose tissue to represent adipose individuals.…”

Effective dose conversion coefficients for health care provider exposed to pediatric and adult victims in radiological dispersal device incident

“…After a RDD event occurs, potentially contaminated victims will go through an external decontamination process and initial screening by portable survey-meters (Bolch et al 2012, Palmer et al 2012 to roughly estimate the internal contamination. If the committed effective dose equivalent is higher than 250 mSv, the individual will be guided to a medical facility for internal dose assessment by whole body counting or urine sampling and medical management will be further processed depending on the result of the assessment (NCRP 2008).…”