As Low As Is Reasonably Achievable Research Articles

Radiation exposure to handheld XRF operators analyzing glass

The number one aim in radiation safety is to keep exposure as low as is reasonably achievable (ALARA). Still, there exist international and national regulations on occupational radiation safety, as well as institutional policies (e.g., ) limiting the amount of radiation a person should be exposed to in their work. Operating a handheld/portable x-ray fluorescence (XRF) spectrometer is not generally considered a highly risky endeavor in terms of radiation exposure, yet there is frustratingly little data available on the subject . This paper shares data from a real-life practical application and compares the radiation levels to an international safety standard, in order to contribute data where there seems to be a relative dearth, so that handheld XRF operators might inform themselves more fully about the risks associated with their work. This paper is limited, however, in that the tests are carried out on one type of material (glass) with one instrument with limited settings and at...

Laryngotracheal anomalies and airway fluoroscopy in infants

ObjectivesThe role of airway fluoroscopy in the diagnosis of laryngotracheal anomalies in infants is controversial. We aimed to (i) compare airway fluoroscopic characteristics with endoscopic findings in infants presenting for evaluation of upper airway obstruction and (ii) assess the as low as is reasonably achievable (ALARA) status for airway fluoroscopy as an initial diagnostic test in suspected laryngotracheal anomalies. Materials and methodsWe performed a retrospective review of children who underwent fluoroscopy and endoscopic evaluation of the airway in the operating room for suspected laryngotracheal anatomic abnormalities. Thirty-four infants who underwent both procedures at a tertiary level university-based children's hospital from January 1, 2008 to December 1, 2013 were included. Infants with suspected foreign bodies or an existing tracheostomy were excluded. Intraoperative findings from endoscopy and radiologic interpretation from fluoroscopy were compared using standard tools for validation of a diagnostic test. These metrics were compared with historic data that suggested good correlation between radiologic and endoscopic findings in older children. ResultsThe median age was 3.6 months (range 1–8 months). The sensitivity of airway fluoroscopy for determining laryngotracheal pathology was 18%. Specificity, positive predictive value and negative predictive value were 83%, 67% and 35%, respectively. Although each fluoroscopic exposure was optimized for pediatric patients, the median cumulative exposure to ionizing radiation was 19 mR (range 10–34 mR). ConclusionsAirway fluoroscopy yields metrics that are overall poor to be considered a valid and accurate universal radiologic diagnostic test in infants evaluated for laryngotracheal pathology. The cumulative exposure to ionizing radiation from use of a fluoroscope cannot be justified by the sensitivity of the test and may not conform to ALARA standards for imaging in this population.

The use of cuprous iodide as a precipitation matrix in the radiochemical determination of 131I in milk.

Abstract As a result of the implementation of the As Low As is Reasonably Achievable (ALARA) philosophy to the nuclear power industry, recent U.S. Nuclear Regulatory Commission (NRC) requirements have prompted high sensitivity radiochemical analysis for the measurement of 131I in milk. The most recognized and commonly employed technique incorporates costly palladium iodide as the final precipitate in the radiochemical purification of the iodine chemical species. The procedure presented in this paper outlines the many advantages of using cuprous iodide as the final precipitate. These include lower cost per analysis, consistent recoveries, better precipitate matrix and good self absorption characteristics. Typical lower limit of detection values and operating characteristics obtained for high sensitivity (3-y analysis as well as gas proportional counting and a comparison of radiochemical and Ge(Li) spectrometric results for environmental samples collected during a recent Chinese weapons fallout incident are presented.