Preliminary studies to develop a personal dosemeter for use by aircraft crew

This paper describes preliminary work to develop a cosmic-radiation dosemeter for use by military aircraft crew. The dosemeter is based on a combination of CR-39 etched-track detectors and TLD-700 thermoluminescent detectors. It is intended that the CR-39 be used to assess the neutron dose, while the TLD-700 is used to assess the photon and charged particle dose. The sensitivity of CR-39 to the neutron component of cosmic radiation was estimated by irradiating samples of the plastic at the CERN-CEC High Energy Reference Field Facility. This facility produced a radiation field with a neutron spectrum resembling that of the neutron component of cosmic radiation at typical airflight altitudes. The response of the CR-39 was linear over the range of doses studied (0.2-6.0 mSv) and there was no significant fading in the 6-month period after irradiation. The TLD-700 component of the dosemeter was calibrated using 137Cs gamma rays. The response of the TLD-700 was linear over the range of doses studied (0.01-5.0 mSv) with no significant fading in the 6-month period after irradiation. It was concluded that a combination of CR-39 and TLD-700 detectors would provide an effective cosmic-radiation dosemeter for use by military aircraft crew.