Contaminant deposition building shielding factors for US residential structures

Abstract

This paper presents validated building shielding factors designed for contemporary US housing-stock under an idealized, yet realistic, exposure scenario from contaminant deposition on the roof and surrounding surfaces. The building shielding factors are intended for use in emergency planning and level three probabilistic risk assessments for a variety of postulated radiological events in which a realistic assessment is necessary to better understand the potential risks for accident mitigation and emergency response planning. Factors are calculated from detailed computational housing-units models using the general-purpose Monte Carlo N-Particle computational code, MCNP5, and are benchmarked from a series of narrow- and broad-beam measurements analyzing the shielding effectiveness of ten common general-purpose construction materials and ten shielding models representing the primary weather barriers (walls and roofs) of likely US housing-stock. Each model was designed to scale based on common residential construction practices and include, to the extent practical, all structurally significant components important for shielding against ionizing radiation. Calculations were performed for floor-specific locations from contaminant deposition on the roof and surrounding ground as well as for computing a weighted-average representative building shielding factor for single- and multi-story detached homes, both with and without basement as well for single-wide manufactured housing-unit.

Building protection- and building shielding-factors for environmental exposure to radionuclides and monoenergetic photon emissions

“…The primary weather barriers selected to define these housing-units are composed of either brick-or vinyl siding for the walls with asphalt shingles for the roof. Dickson et al (2014bDickson et al ( , 2015 developed 98 housingunit models of varying combinations of nine primary weather barriers; five representing exterior walls, four representing roofs. Findings demonstrated that despite differing primary weather barrier compositions, the amount of shielding provided by the structure generally remained consistent for housing-units composed of thin, light materials (vinyl, wood, and stucco).…”

Monte-Carlo simulations of external dose contributions from the surrounding ground areas of residential homes in a typical Northern European suburban area after a radioactive fallout scenario

“…To the best of our knowledge, previous studies have only addressed external dose contributions from unfractionated environmental surfaces (e.g. by Meckbach et al 10 , 11 , Jacob and Meckbach 12 , Kis et al 13 , 14 , Salinas et al 15 , Dickson et al 16 , Dickson and Hamby 17 , and Hinrichsen and Andersson 18 ), such as the whole ground area. In contrast, we have applied the isodose concept to study the external dose contributions inside typical Northern European house models from contamination on the ground with a resolution of 19 .…”

Kerma conversion factors for modern glass buildings in radioactively contaminated areas

“…The applicability of the transport code MCNP6 in determining exposure reduction for a modular building type has been experimentally verified in a previous study by our group . Further Monte Carlo simulations were performed for an industrial area (Kis et al 2003, Kis et al 2004, for various scenarios of U.S. residential structures (Dickson & Hamby 2014, Dickson & Hamby 2016, Dickson et al 2017, for typical houses in Brazil (Salinas et al 2006), and typical buildings in Japan (Furuta & Takahashi 2015). To the best of our knowledge such simulations have not previously been performed for buildings with glass facades that can be found in many cities now as a part of modern architecture or buildings with similar shielding properties.…”