been recorded on over 700 ¯ights, including over 150 ¯ights with Air New Zealand (ANZ). This substantial set of data from the southern hemisphere is an ideal ...
Radiation Protection Dosimetry (2004), Vol. 110, Nos 1-4, pp. 381±386 doi:10.1093/rpd/nch229
TEPC MEASUREMENTS IN COMMERCIAL AIRCRAFT
G. C. Taylor1,, R. D. Bentley2, N. A. Horwood1, R. Hunter3, R. H. Iles2, J. B. L. Jones4, D. Powell5 and D. J. Thomas1 1 National Physical Laboratory, Queens Road, Teddington, Middlesex, TW11 0LW, UK 2 Mullard Space Science Laboratory, Holmbury St Mary, Dorking, Surrey, RH5 6NT, UK 3 Civil Aviation Authority, Aviation House, Gatwick Airport South, Gatwick, West Sussex, RH6 0YR, UK 4 Virgin Atlantic Airways Ltd, Manor Royal, Crawley, West Sussex, RH10 2NU, UK 5 Air New Zealand Ltd, Private Bag 92007, Auckland 1010, New Zealand The collaborative project involving the Mullard Space Science Laboratory (MSSL), Virgin Atlantic Airways (VAA), the UK Civil Aviation Authority (CAA) and the UK National Physical Laboratory (NPL) has been performing tissue-equivalent proportional counter measurements of cosmic ray doses in commercial aircraft since January 2000. In that time data have been recorded on over 700 ¯ights, including over 150 ¯ights with Air New Zealand (ANZ). This substantial set of data from the southern hemisphere is an ideal complement to the London-based measurements performed primarily on VAA ¯ights. Although some ANZ data remains to be analysed, dose information from 111 ¯ights has been compared with the CARI and EPCARD computer codes. Overall, the agreement between the measurements and EPCARD was excellent (within 1% for the total ambient dose equivalent), and the difference in the total effective doses predicted by EPCARD and CARI was 150 keV mmÿ1, which is due to alpha particles and heavy recoils. The `alpha edge', indicative of the maximum energy that an alpha particle can deposit in 2 mm of tissue, can be seen at roughly 400 keV mmÿ1. The peak observable just
