The Results of 5 Sessions of Experimental Study of Local Water Shielding Efficiency to Space Radiation with the Protective Curtain in ISS Crew Cabin

Crew cabins in the ISS Service Module are known to be less shielded from space radiation comparing with the neighboring compartments. To increase the crew cabin shielding a special protective curtain was designed and then delivered to ISS in 2010. The hygienic wipes and towels containing water are stored inside protective curtain in 4 layers thus creating an additional shielding thickness. The protective curtain was installed along the outer wall of the starboard crew cabin. The thickness of outer wall is estimated as 1.5g/cm2(H2O), and the thickness of protective curtain is ~6g/cm2(H2O) thus protective curtain considered to have tangible effect against radiation. To study the radiation shielding effect 12 passive detector packages with thermoluminescent detectors (TLDs) and plastic nuclear track detectors(PNTDs) are used. 6 packages are installed on the protective curtain surface and the other 6 packages are installed directly on the crew cabin wall behind or aside the curtain. The passive detector packages ware exposed in the Service Module starboard crew cabin during 5 sessions in period of 2010-2014 years. Results of both TLD and SSTD are presented. The radiation shielding effect varies from 11% to 48% for absorbed dose and from 5% to 47% for equivalent dose. The results are in good agreement with performed calculations. It is shown that properly mounted local shielding can effectively mitigate the radiation dose in space station compartments.The 20th Workshop on Radiation Monitoring for the International Space Statio