Carbon Dioxide Scrubbers
[This is an article in progress, and is currently being written]
A steady supply of oxygen alone is insufficient to keep astronauts breathing. While the intake of oxygen is essential for respiration, the by-product of this respiration is the exhalation of approximately one kilogram of carbon-dioxide per day.[1] The concentration of this gas in Earth's atmosphere is roughly 0.04%, but in the close confines endured by astronauts, accumulations of CO2 can quickly reach toxic levels.[2]
CO2 Concentration | Symptoms |
---|---|
1% | Drowsiness |
3% | Impaired hearing, increased heart rate and blood pressure, stupor |
5% | Shortness of breath, headache, dizziness, confusion |
8% | Unconsciousness, muscle tremors, sweating |
>8% | Death |
NASA has set strict limits of acceptable CO2 concentration on spacecraft. The longer the duration of the flight, the lower the permissible maximum: for example, while permitting a maximum of 2% for a one-hour period, NASA recommends that the concentration not exceed 0.5% over a 1000-day stay[1] (an as-yet hypothetical duration, as the record for longest consecutive stay in space at the time of writing is held by Russian cosmonaut Valery Polyakov at 438 days[3]).
- ↑ 1.0 1.1 James, J. T., & Macatangay, A. (2009). Carbon Dioxide – Our Common “Enemy.” 8.
- ↑ 2.0 2.1 Freudenrich, C. (2011). How is carbon dioxide eliminated aboard a spacecraft? | HowStuffWorks. Retrieved August 15, 2019, from HowStuffWorks website: https://science.howstuffworks.com/carbon-dioxide-eliminated-aboard-spacecraft.htm
- ↑ Wall, M. (2019). Most Extreme Human Spaceflight Records of All Time | Space. Retrieved August 15, 2019, from Soace.com website: https://www.space.com/11337-human-spaceflight-records-50th-anniversary.html