Characterization of the Radiation Shielding Properties of US andRussian EVA Suits

Technical Report · Fri Oct 26 04:00:00 EDT 2001

DOI:https://doi.org/10.2172/901218· OSTI ID:901218

Benton, E R; Benton, E V; Frank, A L

Reported herein are results from the Eril Research, Inc.(ERI) participationin the NASA Johnson Space Center sponsored studycharacterizing the radiation shielding properties of the two types ofspace suit that astronauts are wearing during the EVA on-orbit assemblyof the International Space Station (ISS). Measurements using passivedetectors were carried out to assess the shielding properties of the USEMU Suit and the Russian Orlan-M suit during irradiations of the suitsand a tissue equivalent phantom to monoenergetic proton and electronbeams at the Loma Linda University Medical Center (LLUMC). Duringirradiations of 6 MeV electrons and 60 MeV protons, absorbed dose as afunction of depth was measured using TLDs exposed behind swatches of thetwo suit materials and inside the two EVA helmets. Considerable reductionin electron dosewas measured behind all suit materials in exposures to 6MeV electrons. Slowing of the proton beam in the suit materials led to anincrease in dose measured in exposures to 60 MeV protons. During 232 MeVproton irradiations, measurements were made with TLDs and CR-39 PNTDs atfive organ locations inside a tissue equivalent phantom, exposed bothwith and without the two EVA suits. The EVA helmets produce a 13 to 27percent reduction in total dose and a 0 to 25 percent reduction in doseequivalent when compared to measurements made in the phantom head alone.Differences in dose and dose equivalent between the suit and non-suitirradiations forthe lower portions of the two EVA suits tended to besmaller. Proton-induced target fragmentation was found to be asignificant source of increased dose equivalent, especially within thetwo EVA helmets, and average quality factor inside the EMU and Orlan-Mhelmets was 2 to 14 percent greater than that measured in the barephantom head.

• Research Organization: Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
• Sponsoring Organization: USDOE Director, Office of Science; National Aeronautics andSpace Administration
• DOE Contract Number: AC02-05CH11231
• OSTI ID: 901218
• Report Number(s): LBNL--48977
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
ASTRONAUTS
DOSE EQUIVALENTS
ELECTRON BEAMS
ELECTRONS
FRAGMENTATION
INTERNATIONAL SPACE STATION
MEDICAL ESTABLISHMENTS
NASA
ORGANS
PHANTOMS
PROTON BEAMS
PROTONS
QUALITY FACTOR
RADIATION DOSES
RADIATIONS
SHIELDING
Space suits EVA
TARGETS