Inter-Module Ventilation Changes to the International Space Station Vehicle to support separated USOS and RSOS atmospheres in support of troubleshooting CO2 removal hardware



Journal Title

Journal ISSN

Volume Title


47th International Conference on Environmental Systems


The International Space Station (ISS) Environmental Control and Life Support System (ECLSS) maintains two integrated, but separately capable Operational Segments, the Russian On-Orbit Segment (RSOS) and the US On-Orbit Segment (USOS). In the summer of 2016 the atmospheres of the two segments were effectively separated without blocking the emergency egress path or disrupting nominal crew operations between the US and Russian sides of the ISS. The goal was to provide a troubleshooting tool, allowing insight on performance of the currently operating Carbon Dioxide Removal Assembly (CDRA) and the Russian Vozdukh without having to shut down either unit. This paper will examine the available options discussed, step through the hardware and operational changes made to the ventilation system, and review the results. This paper will then debrief the usefulness of this approach for the CO2 troubleshooting activity, and investigate its future use.


Steven Balistreri, The Boeing Company, USA
Kevin Braman, The Boeing Company, USA
ICES404: International Space Station ECLS: Systems
The 47th International Conference on Environmental Systems was held in South Carolina, USA on 16 July 2017 through 20 July 2017.


ECLS, Carbon Dioxide, CDRA, Ventilation, International Space Station, Life Support