A Pressure Ionization Chamber For The Measurement Of Neutron Fluxes At Tolerance Level In Portable Instruments

The largest daily fast neutron dose considered safe for the human body (tolerance dose) is taken to be 0.01 n units. If this dose is received during an 8 hour working day, The neutron flux has to be such as to provide an average dose rate of 0.01 n units per 8 hours. An instrument of high sensitivity is needed to measure fluxes of such order of magnitude in a reasonably short time and within a reasonably small space. High pressure ionization chambers as well as counters will serve the purpose. Which of the two should be chosen depends on what appears the most satisfactory compromise in fulfilling the following requirements: (1) The instrument should read as nearly proportional as possible to the biological effect, independently of the energy of the fast neutrons. (2) The instrument should have a high neutron to gamma sensitivity ratio, compared with the 100 r Victoreen chamber. (3) The instrument should be of rugged and simple construction and require no accessories that would make the total weight in excess of what is conveniently portable.

Consists of AECD 1-2023 (no. 1-1779 called MDDC).

This index is designed to cover the declassified and unclassified work of the University of Rochester Atomic Energy Project from its beginning in 1943 until July 1960. It contains titles of the work described in Manhattan District and Atomic Energy Commission reports as well as of material published in books and journals.