title: Calculation of the air concentrations of serially decaying nuclides--a new method applied to radon progeny.
abstract: A new calculation method is presented for determining the air concentrations of any serially decaying nuclides. This new method is easily incorporated into a Basic or spreadsheet program that is used to record the decay data. Specifically, the measurements were designed to illustrate radon progeny from a filter sample that is gross-alpha counted. The method is based on regressing the decay data, recorded in 1-min intervals, on the time after the end of sampling with an equation that describes the alpha activity as a function of the decay exponentials, e-lambdat. The results from both generated data and experimental filter samples were compared to the results obtained by two other well-known methods. All the methods give comparable estimates for the progeny air concentrations; non-linear regression and weighting by variances produces the smallest error estimates with the method presented here.
authors.affiliation: New York University School of Medicine, Nelson Institute of Environmental Medicine, NY 10016, USA. heikkm01@med.nyu.edu
authors.forename: M S
authors.initials: MS
authors.lastname: Heikkinen
authors.forename: N H
authors.initials: NH
authors.lastname: Harley
mesh_terms: D000396:Air Pollutants, Radioactive / Q000032:analysis* / Q000737:chemistry; D000512:Alpha Particles; D004784:Environmental Monitoring / Q000379:methods; D005374:Filtration / Q000295:instrumentation; D008432:Mathematical Computing; D011874:Radiometry / Q000379:methods; D017687:Radon Daughters / Q000032:analysis* / Q000737:chemistry
chemical_list: D000396:Air Pollutants, Radioactive; D017687:Radon Daughters