Irraggiamento delle persone nei voli commerciali Australia-USA (20 ottobre)

Nota: in questo studio non si fa cenno dei modelli di aerei utilizzati (se o meno con uranio impoverito) né delle radiazioni subite al check-in dell'aeroporto per il controllo antiterrorismo.


Radiation Measurements 32 (2000) 43-48
Analysis of neutron and gamma ray doses accumulated during commercial Trans-Pacifc flights between Australia and USA
B. Mukherjee (a), P. Cross (b)

(a) Safety Division, ANSTO, PMB 1, Menai, NSW 2234, Australia
(b) Radiation Oncology Department, St Vincent's Hospital, Darlingshurst, NSW 2021, Australia

* Corresponding author: E-mail address: mukherjee@ieee.org (B. Mukherjee).

Received 5 February 1999; received in revised form 19 July 1999
articolo-completo-in-formato.PDF

Abstract

During recent commercial Trans-Pacifc passenger flights between Sydney and several major cities in the USA, the neutron and gamma dose equivalents in the aircraft cabin were evaluated with superheated Bubble dosimeters, thermoluminescence dosimeter chips (TLD-600 and TLD-700) and a miniature electronic dosimeter. After a total 73-hour flight time the accumulated neutron and gamma dose equivalents were evaluated to be 39.7 µSv and 74.0 µSv respectively. The thermoluminescence (TL) glow curves of the dosimeter chips were assayed at a ramp heating rate of 10°C s-1 up to 400°C. By using the Bubble and electronic dosimeter data it was possible to isolate explicitly the neutron and gamma dose components from the deconvoluted TL-glow curve of the TLD-600 chips. The application of Bubble dosimeter and TLD for an accurate estimation of the radiation exposure to air crews and frequent flying passengers is suggested.

(c) 2000 Elsevier Science Ltd. All rights reserved.
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1. Introduction

At high cruising altitudes the cabin crews, pilots and passengers in commercial jetliners are exposed to radiation fields above the natural background level (O'Brien et al., 1992). These radiations are primarily fast neutrons, muons and bremsstrahlung photons produced by the galactic cosmic ray induced reactions in the upper atmosphere and to a lesser extent in the structure of the aircraft itself (Reitz, 1993). The levels of the radiation exposure in the high altitude aircraft are directly related to flight duration, altitude, geographical latitudes traversed by the flight path, time of the year and the intensity of the solar activity (Reitz, 1993).

The radiation doses in commercial passenger jet airliners during the flights in numerous Northern Hemisphere destinations in Europe (Reitz, 1993; Regulla and David, 1993; Bartlett, 1993) and in America (Lewis et al., 1994) have been evaluated using various types of active and passive dosimeters and reported elsewhere. Also, the in-flight radiation dose data in Frankfurt-Singapore-Sydney-Melbourne (Regulla and David, 1993) and in major Australian domestic routes (Wilson et al., 1994) have been investigated. On the other hand, no relevant data for the commercial lights between south-pacifc region to North America has yet been published. In this paper the results of an in-flight neutron and gamma dose analysis experiment between Sydney and some major US cities are presented...

(...)


3. Results and discussion

(...) Although these results generally confrm the radiation dose to aircrew and to passengers does have a substantial neutron component, as expected, the results also indicate that for flights within the commercial height range, aircrew, and frequent flying passengers, may well be subject to radiation dose levels significantly above that permitted for members of the `public' under statutory recommendations (ICRP-60, 1990). It is therefore recommended that a more thorough investigation be carried out, particularly on the Pacifc region long-haul routes.

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