[Lipothymia].

The neutron dose equivalent in aircraft is measured using commercial bubble detectors, but at high altitudes there are not only neutrons but also protons. Bubble detectors have been used because they are considered not to be sensitive to protons, but this has been the subject of only a few studies. In this study, by irradiating bubble detectors with energetic protons, the detectors' responses to protons were observed. Bubbles were clearly formed by protons, but the proton sensitivities were one order of magnitude smaller than the neutron sensitivities. Thus, counts of protons can be ignored in neutron measurements in aircraft.

Aerospace Medicine↗

PubMed2004

Assessment of aircrew radiation exposure by further measurements and model development.

A methodology is presented for collecting and analysing exposure measurements from galactic cosmic radiation using a portable equipment suite and encapsulating these data into a semi-empirical model/Predictive Code for Aircrew Radiation Exposure (PCAIRE) for the assessment of aircrew radiation exposure on any flight over the solar cycle. The PCAIRE code has been validated against integral route dose measurements at commercial aircraft altitudes during experimental flights made by various research groups over the past 5 y with code predictions typically within +/-20% of the measured data. An empirical correlation, based on ground-level neutron monitoring data, is detailed further for estimation of aircrew exposure from solar particle events. The semi-empirical models have been applied to predict the annual and career exposure of a flight crew member using actual flight roster data, accounting for contributions from galactic radiation and several solar energetic-particle events over the period 1973-2002.

Aerospace Medicine↗