Exposure Calculator, Gamma, “CTI Mk.VIIl”

Description
Exposure Calculator, Gamma, “CTI Mk.VIIl”
(previously SCRATA) for Iridium 192, Cobalt 60 & Ytterbium 169 isotopes.
This Castings Technology isotope exposure calculator is a pocket slide rule used for calculating correct exposure time for gamma radiography of Iridium 192, Cobalt 60 & Ytterbium 169 isotopes.