NO9700102 \ FE/IFE/kR/E-96/008 Cosmic radiation and airline pilots. Exposure patterns of Norwegian SAS-pilots 1960 to 1994 February 1997 Institutt for energite|<nikk Institute for Energy Techri&logy IFE/IFE/KR/E-96/008 COSMIC RADIATION AND AIRLINE PILOTS. EXPOSURE PATTERNS OF NORWEGIAN SAS-PILOTS 1960 TO 1994 BY ULFTVETEN February 1997 INSTITUTE FOR ENERGY TECHNOLOGY KJELLER, NORWAY Performing Organisation Document no.: Date Institutt for energiteknikk IFE/KR/E-96/008 February 1997 Kjeller Project/Contract no. and name Client/Sponsor Organisation and reference: E-483 EU-prosjekt Title and subtitle Cosmic radiation and airline pilots. Exposure patterns of Norwegian SAS-pilots 1960 to 1994. Author(s) Approv6d/^^'-^-J UlfTveten Gordon Christensen Gordon Christensen Institute for Energy Technology, Kjeller Abstract The work which is presented in this report is part of a Norwegian epidemiological project, carried out in cooperation between Institute for Energy Technology (1FE), the Norwegian Cancer Registry (NCR) and the Norwegian Radiation Protection Authority (NRPA). The project has been partially financed by the Norwegian Research Council. Originating from the Norwegian project, a number of similar projects have been started or are in the planning stage in a number of European countries. The present report lays the ground for estimation of individual exposure histories to cosmic radiation of pilots employed by the Scandinavian Airline System (SAS). The results presented in this report (radiation doserates for the different types of aircraft in the different years) will, in a later stage of the project, be utilized to estimate the individual radiation exposure histories. The major sources of information used as basis for this work is the collection of old SAS time tables found in the SAS Museum at Fornebu Airport in Oslo, and information provided by members of the Pilots Associations. Key Words Cosmic radiation, Cancer, Aviation ISSN ISBN Numbers of Pages 0333-2039 82-7017-160-3 106 Supplementary Data ACKNOWLEDGEMENTS The author wants to express his gratitude for the valuable help given by the Norwegian Pilots Association, the SAS (Scandinavian Airlines System) Pilots Association, the SAS Museum, and in particular the flight captains Odd Iversen and Olav Eide and copilot Stein Gilhuus. He also wants to thank Wallace Friedberg of the Civil Aviation Institute, Oklahoma City for providing the computer program CARI-3N, which has been used to calculate the radiation doses presented in this report. TABLE OF CONTENTS 1 Introduction 1 2 The epidemiological project 1 3 Alternative approaches to radiation dose estimates 2 4 Information from the SAS time tables 3 5 Aircraft types and pilots per aircraft 5 6 Distribution of pilot-hours on different types of routes 6 7 Flight profiles for different routes 6 8 Heliocentric potential over the time period considered 7 9 Change of airport locations 8 10 Calculation of the radiation dose and doserate along specific flight legs, using the CARI-3N computer program 8 11 Typical radiation doserate on specific aircraft types over the years 1960 to 1994 9 Appendix A Flight-hours per week flown by Norwegian SAS-pilots 10 Appendix B Flight profiles for SAS routes 17 Appendix C Radiation doses and doserates to Norwegian SAS-pilots on specific flights 59 1 Introduction The work which is presented in this report has been performed as part of a Norwegian epidemiological project entitled «Exposure to low level ionizing radiation and incid- ence of cancer in airline pilots and crew», carried out in cooperation between Institute for Energy Technology (IFE), the Norwegian Cancer Registry (NCR) and the Norwe- gian Radiation Protection Authority (NRPA). IFE was initiator of the project, and acts as project leader. The project has been partially financed by the Norwegian Research Council. Originating from the Norwegian project, a number of similar projects have been star- ted or are in the planning stage in a number of European countries. Interest has also been expressed from institutions in the USA and Canada. Attempts to form a European project combining all these efforts failed twice to obtain funding from the European Union. Other means of financing the project work and meetings, in order to obtain a satisfactory level of coordination and cooperation between the national projects are presently being sought. The present report lays the ground for estimation of individual exposure histories to cosmic radiation of pilots employed by the Scandinavian Airline System (SAS). The results presented in this report (radiation doserates for the different types of aircraft in the different years) will, in a later stage of the project, be utilized to estimate the indivi- dual radiation exposure histories. The major sources of information used as basis for this work is the collection of old SAS time tables found in the SAS Museum at Fornebu Airport in Oslo, and informa- tion provided by members of the Pilots Associations. 2 The epidemiological project The present project is based upon a concept conceived in 1981 by the author of the present report in cooperation with Georg Petersen, MD, then at the Oslo Health Coun- cil, presently United Nations Expert stationed in Cambodia. The concept was further developed in 1982, and subsequently submitted as a project proposal to the Norwegian Research Council. Although the proposed project won the approval of the Civil Avia- tion Administration and was granted the necessary permissions from the Cancer Regis- ter and the Data Inspectorate, adequate funding was not obtained, and the project was dormant until 1992, when a renewed and extended project proposal was submitted to the Commission of the European Communities' Radiation Protection Programme (RPP). In addition to the institutions mentioned in Chapter 1, the planned project par- ticipants were the German Cancer Research Center, Heidelberg and the Wageningen University, Department of Epidemiology and Public Health, Netherlands. The project was subsequently approved by the RPP. A feasibility study was funded, which should include airline pilots and, if feasible, cabin crew licensed in Norway, and was carried out by the Norwegian participants in the project proposal. The Norwegian cohort has now been established by NCR, and extensive quality con- trol and evaluation of the completeness of the cohort has been carried out. The cohort consists of all pilots and cabin crew in the registers of the Norwegian Aviation Admini- stration since 1 January 1946 for the pilots and from 1 January 1950 for cabin crew and up till 18 February 1994. There are about 3,800 pilots and 3,000 cabin crew in the cohort. 3 Alternative approaches to radiation dose estimates In the initial stages of the project several alternative approaches were considered. The flight hours of the individual pilots between licence renewals are registered in the Nor- wegian Aviation Administration and have been entered into the cohort data base. This, however, has to be seen in conjunction with information on the type of routes flown. One reason for this is that the reported flight hours include the taxing time (time from departure from the gate until take-off and time from touch-down to arrival at the gate). For short flights the taxing time, when no excess radiation is received, is a much larger proportion of the flight time than for long flights. It was found that in the Norwegian material the aircraft type was available for the majority of the pilots. If this had not been the case, use of a typical career pattern was considered. Typically a commercial pilot starts as co-pilot on short flights, advance to continental routes and finally to intercontinental routes, before advancing to captain on short routes etc. For cabin crew it does not appear that historic data on flight hours are available. The dose history then has to be based on the information available, e.g. duration of employ- ment. Further investigations on availability of data are on-going. In the present project it has been chosen to make detailed estimation of the individual dose exposure histories, based on information on aircraft type, for all pilots within the cohort employed by SAS. A similar effort ought to have been carried out for pilots employed by the other larger Norwegian airlines (Braathens SAFE, Wider0e and per- haps a few others), but this has not been possible on the funds available. At least for the time being the exposure histories of these pilots will be estimated in the same manner as for SAS pilots flying the same type of aircraft. Very early in the project period it was decided to base the dose calculations on the computer program CARI-3N, developed at the US Federal Aviation Administration. See ref. (Friedberg et al) for information about this program. The program is widely used for calculations of this type. The program calculates doses along defined flight routes, but the question remained: how to choose the flight routes for the individual pilots in the cohort. The files of the Aviation Administration contain a large number (several hundred) of types of aircraft flown by pilots within the cohort. All types of aircraft not used by SAS have been assembled in classes according to typical cruise altitude, typical flight profile as well as route (departure and destination airports) have been defined, and calcula- tions of doserates for each "altitude class" has been carried out. This task could not have been carried out without the invaluable assistance of a number of commercial pilots, and coordinated by co-pilot Stein Gilhuus of SAS and co-pilot Peter Bull of Braathens SAFE. The calculations of doses and doserates for aircrafts not used by SAS will be presen- ted in a separate report. 4 Information from the SAS time tables All routes from the SAS time tables were entered in tables in an ACCESS data base.