Research and analysis
GRANIS: assessment model for external photon irradiation
This report (HPA-RPD-032) describes the Gamma Radiation Above Nuclides In Soil (GRANIS) model for calculating external photon dose.
HPA-RPD-032: GRANIS: a model for the assessment of external photon irradiation from contaminated media of infinite lateral extent
Ref: ISBN 978-0-85951-606-8 PDF, 362KB, 70 pages
This file may not be suitable for users of assistive technology. Request an accessible format.
If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email email@example.com. Please tell us what format you need. It will help us if you say what assistive technology you use.
GRANIS is a model developed by the Health Protection Agency (HPA) to calculate the external photon dose from layers of contaminated material which have finite thickness yet are effectively infinite in horizontal extent. The model allows different vertical activity profiles to be considered, so has particular application for the prediction of external gamma irradiation following the deposition of radionuclides to ground following short or continuous releases to the environment. GRANIS calculates effective dose and equivalent dose for 4 tissues.
This report describes the theory behind the GRANIS version 3 model and includes results calculated for a set of typical cases.