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.Work performed at the University of Rochester."Date Declassified: April 12, 1948."Includes bibliographical references.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.Mode of access: Internet