Skip to main content

A Review of the Radiological Assessments Corporation's Fernald Dose Reconstruction Report (1997) / Chapter Skim
Currently Skimming:

SPECIFIC COMMENTS ON VOLUME II: THE TECHNICAL APPENDIXES
Pages 30-34

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 30...
... Appendix El: Particle Size Distributions for Dust Collectors RAC has chosen to accomplish several things in this appendix, including fitting the cascade-impactor data by exact polynomial equations, simulating mathematically the action of an Andersen impactor by describing the jet configurations and air flows to match the airsampling process, and comparing this approach to conventional particle-size analysis by using lognonnal clistr~bution assumptions and probit analyses to obtain mass median aerodynamic diameters (MMADs)
Read the entire page →
From page 31...
... The authors recognize this when they state that "when particle bounce occurs, distorted efficiency curves are effectively being substituted for the theoretical curves on which the analysis is based." However, little contribution is attributed to this phenomenon, as seen on page H-10, paragraph 4: "In the F~C sampling, however, we believe the comparisons of the sampling data with the simulated data points, which were computed with the theoretical curves, cast doubt on the presence of such levels of degradation of collection efficiency." This theoretical simulation of the impactor does not account for particle bounce, and the polynomial equations fit the data without accounting for any.
Read the entire page →
From page 32...
... In accepting any problems with the simulation, however, the authors state that "this result reassures us that accepting at face value the sample points from the 198S EKES study is a reasonable procedure for drawing conclusions about the form of the sampled distribution. It says nothing, of course, about the relationship of the distribution at the time of sampling with comparable distributions over time." All in all, the computer simulation of the Andersen cascade impactor with the mathematics presented is acceptable.
Read the entire page →
From page 33...
... Appendix S: Lifetime Risks of Fatal Cancer for Individual Scenarios at the Feed Materials Production Center Page S-4, table S-2: These risk estimates, which are based on data from the Japanese atomic bomb survivors, are dominated by the digestive tract, with the colon having 17% and the stomach 27% of the total risk. In western populations that have been studied, the percentage of total radiation risk associated with those sites appears to be much smaller.
Read the entire page →
From page 34...
... studies, the text essentially ignores any comparison of the observed deficit in lung cancer with the BEIR IV risk estimate (NRC 1988) , but instead focuses on a small apparent excess of Iymphohematopoietic cancers in the studies.
Read the entire page →

Key Terms

  • size distributions
  • respiratory tract
  • geometric standard
  • risk estimates
  • theoretical curves

  • mass median
  • lognormal distribution
  • particle bounce
  • polynomial equations
  • sampler data

  • western populations
  • sampled distribution
  • standard deviations
  • median aerodynamic
  • cascade impactor

  • risk associated
  • prior assumption
  • including fitting
  • feed materials
  • bounce occurs

  • tract deposition
  • authors recognize
  • yields deposition
  • size data
  • reasonable procedure

  • distorted efficiency
  • risk estimate
  • efficiency curves
  • aerodynamic diameter
  • rapid assessment


    • This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
    More information on Chapter Skim is available.