Giovanni De Angelis

A retrospective cohort mortality study of Italian commercial airline cockpit crew and cabin attendants, 1965-96.

Abstract A retrospective cohort mortality study was conducted among Italian commercial flight personnel for the period 1965-1996. The cohort was composed of 3,022 male cockpit crew members and 3,418 male and 3,428 female cabin attendants. Cause-specific standardized mortality ratios (SMRs) and exact 95% confidence intervals. (CIs) were calculated as estimates of the relative risk. Mortality from all cancers was less than expected forall categories (SMRs of 0.58 for male cockpit crew, 0.67 for male cabin attendants, and 0.90 for female cabin attendants). Among male flight persopnel, the SMR for leukemia was somewhat elevated (SMR 1.73; 95% CI: 0.75–3.41) based on eight deaths, with a positive trend by length of employment (p = 0.046). Additionally, an excess of death by suicide was seen among female cabin attendants (SMR 3.38; 95% CI: 1.24–7.35). Other Italian studies of flight personnel are under way, including a detailed assessment of cosmic radiation exposure and investigations of non-radiation occupational risk factors and prevalence of nonfatal outcomes.

Radiation Shielding Analysis for Deep Space Missions

An environment for radiation shielding analysis for manned deep space mission scenarios has been developed. The analysis is performed by dividing a mission scenario into three possible different phases, namely the interplanetary cruise phase, the final planetary approach and orbit insertion, and the surface phase. In the first phase only Galactic Cosmic Rays and Solar Events particles are used, in the second phase the effects of trapped radiation belts are also taken into account, and in the third phase also the effect of the planetary environment is considered. Planetary surfaces and atmospheres are modeled based on results from the most recent targeted spacecraft. The dose results are coupled with mission design visualization techniques.

Dynamic/Anisotropic Low Earth Orbit Environmental Models

The first level of space infrastructure is represented by the International Space Station (ISS), which is now permanently occupied by space career astronauts. It is imperative that we understand the ISS exposures dynamically for career planning and insure that the regulatory requirement of keeping exposures as low as reasonably achievable (ALARA) is adequately implemented. This is especially true as ISS matures with increasing complexity resulting in a larger drag coefficient requiring operation at higher altitudes with increased exposure rates. In applying ALARA, it is desirable to augment the shielding in areas where the crew spends significant amounts of time. One such area is the crew quarter that has the added problem of being generally located against the pressure vessel wall where shielding is minimal and exposure rates tend to be high. A significant portion of the exposure results from trapped protons and is highly directional. In addition, some directions of approach of galactic cosmic rays are shielded below the Earth’s horizon and greater numbers of low energy particles enter from the west than the east. Clearly, the augmentation requires an understanding of this directionality to block major radiation components. We describe herein a new model of trapped and galactic cosmic radiation as seen in ISS operations in preparation for the design of an augmentation of the ISS crew quarter.