Developing a Low Budget System to Mix, Store, and Deliver Enhanced Respiratory Gases for Human Research in Liberal Arts College Setting

Paul Frank Martino





Carbon dioxide (CO2) levels are elevated on the International Space Station, and preliminary reports associate this increased CO2 with headaches, changes in vision, and enhanced emotional experiences, including anxiety. As the duration of space travel extends, improved understanding of the physiologic effects of elevated CO2 exposure is necessary to ensure the capabilities and safety of astronauts. However, studying human breathing has proven difficult at small liberal arts college due to cost and laboratory space constraints. Therefore, the goal of this project is to develop and validate a low budget system that can accurately and dependably mix, store, and deliver enhanced respiratory gases for human research in a liberal arts college setting. Our results provide user-friendly guidelines for building, validating, and maintaining such a system, and broad implementation of this system may increase the quantity and diversity of respiratory research relevant for space travel.


CO2; Gas mixing and delivery; Extended Space Travel

Full Text:



Bailey, J. E., Argyropoulos, S. V., Kendrick, A. H., & Nutt, D. J. (2005). Behavioral and cardiovascular effects of 7.5% CO2 in human volunteers. Depression and Anxiety, 21, 18-25.

Forster H.V., Murphy C.L., Brice A.G., Pan L.G., Lowry T.F. (1990). In vivo regulation of plasma [H+] in ponies during acute changes in PCO2. J Appl Physiol, 68(1): 316-21.

Gladstone, G., & Parker, G. (2005) Measuring a behaviorally inhibited temperament style: Development and initial validation of new self-report measures. Psychiatry Research, 135, 133-143.

Gorman, J. M., Kent, J., Martinez, J., Browne, S., Coplan, J., & Papp, L. A. (2001). Physiological changes during carbon dioxide inhalation in patients with panic disorder, major depression, and premenstrual dysphoric disorder. Archives of General Psychiatry, 58, 125-131.

Gutting S.M., Forster H.V., Lowry T.F., Brice A.G., Pan L.G. (1990) Respiratory muscle recruitment in awake ponies during exercise and CO2 inhalation. Respir Physiol, 86(3): 315-21.

Law J, Van Baalen M, Foy M, Mason SS, Mendez C, Wear ML, Meyers VE, Alexander D. (2014). Relationship between carbon dioxide levels and reported headaches on the international space station. J Occup Environ Med.;56(5):477-83.

Stankovic, A., Alexander, D., Oman, C.M., Schneiderman, J. (2016). A Review of Cognitive and Behavioral Effects of Increased Carbon Dioxide Exposure in Humans. Technical memorandum, NASA Center for AeroSpace Information (CASI).

Watkins W., Hargens A.R., Seidl S., Clary E.M., Macias B.R. (2017). Lower-body negative pressure decreases noninvasively measured intracranial pressure and internal jugular vein cross-sectional area during head-down tilt. J Appl Physiol. 123(1): 260-266.

Widmaier E.P., Raff H., Strang, K.T. (2008) Vander’s Human Physiology, New York, NY: McGraw-Hill



  • There are currently no refbacks.

Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.