Purpose of this RFI: The objective of the pilot chamber testing is to validate chamber facility and test team capabilities to support NASA decompression sickness (DCS) studies supporting NASA's development of the Aerospace Estimation Tool for Hypobaric Exposure Risk (AETHER). Facilities are requested to perform 3 test days, collecting and recording data each day as they would for a research protocol. The first day of testing may be considered practice session with the recognition that some facilities and/or hardware integration issues may arise. The second day of testing should be scheduled after issues from the previous run have been resolved, and testing should be completed without interruption, unless otherwise indicated. The third day of testing should occur in the same work week as the second test day to demonstrate the facility's capability to perform multiple runs in short order. This last capability is important because NASA's main objectives in engaging other facilities include an increased tempo of data collection to develop a comprehensive model of DCS risk during spaceflight across a range of conditions that will inform requirements for future vehicles, habitats, suits, and mission planning. At the discretion of NASA, a fourth test day may be required if unresolved deficiencies in performance persist after the third test day. NASA's own facilities will support this work in part but are shared with other operationally relevant tasks/programs, limiting NASA facilities' overall availability and impacting scheduling and completion of critical work. Identification and validation of non-NASA resources to support these DCS research objectives are important steps to facilitating safe and successful prebreathe procedures and extravehicular activity (EVA) in weightlessness and during exploration missions. Budget for this work is firm fixed price. Budget quotes can include payments for interim milestone completion. Dates for each interim milestone should be set by the supplier. Subjects Facilities will recruit and screen applicants to provide at least 3 subjects and up to one test operator (tinder/ultrasound technician) per day to participate in at least 3 test days to fulfill the requirements described above. Each test day is anticipated to last approximately 12 hours. Each of the three single day runs will have unique subjects. Screening back-up subjects in case of subject availability issues, withdrawal, or disqualification is highly recommended. Facilities should screen subjects per their standard protocols, and the subject pool should include females to demonstrate their capabilities to recruit and test this important population. NASA will provide inclusion and exclusion criteria for a population demographic similar to the astronaut corps. As part of the screening process, subjects must pass a medical exam similar to a private-pilot flight physical and complete a peak (maximal) oxygen consumption (VO2pk) test using a cycle …