An empirical approach to the measurement of the cosmic radiation field at jet aircraft altitudes

Abstract Researchers at the Royal Military College of Canada have accumulated extensive dose measurements performed at jet altitudes on over 160 flights and with a wide variety of detectors including a tissue equivalent proportional counter (TEPC), a smart wide energy neutron detection instrument (SWENDI), bubble detectors, thermoluminescent detectors (TLD) and an ion chamber. The summation of the individual low and high LET results from the latter equipment compared successfully to those from the TEPC on each flight. The data from these numerous worldwide flights have been encapsulated into a program that calculates the radiation dose for any flight in the world at any period in the solar cycle. This experimentally based program, Predictive Code for AIRcrew Exposure (PCAIRE) has been designed to be used by the airline industry to meet national dosimetry requirements. In Canada, for example, such a code can be used, supported by periodic measurements. With this latter requirement in mind and a desire to decrease equipment size, the silicon-based LIULIN-4N LET (linear energy transfer) spectrometer has been assessed to determine its suitability as a mixed field instrument and possible code verification tool. Data obtained from the LIULIN and TEPC in ground-based experiments at the CERN-EC Reference-field Facility (CERF) and on 42 jet-altitude flights have been compared. Analysis of these data has resulted in two different mathematical correlations which can be used to determine the ambient dose equivalent, H ∗ (10), from the LIULIN absorbed dose output. With either calibration factor, the LIULIN instrument could now be used as a simple, compact and portable detector for routine monitoring.

[1]  A. R. Green,et al.  Aircrew exposure from cosmic radiation on commercial airline routes. , 2001, Radiation protection dosimetry.

[2]  T. Dachev,et al.  Measurements in an aircraft during an intense solar flare, ground level event 60, on April 15, 2001. , 2001, Radiation protection dosimetry.

[3]  A. Waker,et al.  Neutron Spectrometry and Dosimetry in Specific Locations at Two CANDU Power Plants , 1996 .

[4]  K O'Brien,et al.  Atmospheric cosmic rays and solar energetic particles at aircraft altitudes. , 1996, Environment international.

[5]  Anthony J. Keane,et al.  Cosmic Radiation , 1932, Nature.

[6]  R. Bentley,et al.  The evaluation and use of a portable TEPC system for measuring in-flight exposure to cosmic radiation. , 2002, Radiation protection dosimetry.

[7]  U. J. Shrewe.  Global Measurements of the Radiation Exposure of Civil Air Crews from 1997 to 1999 , 2000 .

[8]  A. R. Green,et al.  Galactic and solar radiation exposure to aircrew during a solar cycle. , 2002, Radiation protection dosimetry.

[9]  V. Ptuskin,et al.  Galactic cosmic rays , 2001 .

[10]  T. Dachev,et al.  Measurements on Board an Aircraft during an Intense Solar Flare, Grond Level Event 60, on April 15, 2001 (Letter to the Editor) , 2001 .

[11]  J. V. van Dijk.  Dose assessment of aircraft crew in The Netherlands. , 2003, Radiation protection dosimetry.

[12]  G Reitz,et al.  Calibration results obtained with Liulin-4 type dosimeters. , 2002, Advances in space research : the official journal of the Committee on Space Research.

[13]  A. R. Green,et al.  Assessment of aircrew radiation exposure by further measurements and model development. , 2004, Radiation Protection Dosimetry.

[14]  J. Barth,et al.  Space, atmospheric, and terrestrial radiation environments , 2003 .

[15]  Icrp.  1990 Recommendations of the International Commission on Radiological Protection , 1991 .

[16]  T. Dachev,et al.  Long-term monitoring of the onboard aircraft exposure level with a Si-diode based spectrometer. , 2003, Advances in space research : the official journal of the Committee on Space Research.