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How do EVA suits manage water excretion?


Does an astronaut sweat in a space suit?Do astronauts lose potassium faster than terrestrial humans?How much protection do space EVA suits offer against radiation for the wearer?Why use fingers in EVA suits?How do astronauts on EVA deal with nose itching?Does an astronaut sweat in a space suit?How do astronauts deal with micrometeorites during EVA?Could astronauts wear EVA suits in the Soyuz?Have astronauts gotten sick on EVA?Can modern EVA spacesuit be put on/taken off by single person, without assistance?Why were EVA suits never silver?How old are the EVA space suits that are currently used on the ISS?






.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty{ margin-bottom:0;
}







7












$begingroup$


This answer immediately sparked the question in my mind of how space suits manage water excretion from the person wearing them. I am aware that the astronauts had to wear diapers since one may need to pee during an hours long EVA. However this only manages the liquids exiting the person.



If during the course of a long and strenuous EVA astronauts lose several pounds of liquid to sweat and breathing, how does the EVA suit manage all this water? They may have a thermal management system to reduce sweating, but that doesn't solve the breathing issue. I can't imaging they let water/water vapor build up inside the suit, it would make the suit environment extremely uncomfortable.










share|improve this question









$endgroup$














  • $begingroup$
    I’m pretty sure they have a dehumidifier as part of the breathing oxygen loop
    $endgroup$
    – CourageousPotato
    8 hours ago






  • 1




    $begingroup$
    The LCVG included ventilation ducts: en.wikipedia.org/wiki/Liquid_cooling_and_ventilation_garment, en.wikipedia.org/wiki/Primary_life_support_system
    $endgroup$
    – Polygnome
    8 hours ago




















7












$begingroup$


This answer immediately sparked the question in my mind of how space suits manage water excretion from the person wearing them. I am aware that the astronauts had to wear diapers since one may need to pee during an hours long EVA. However this only manages the liquids exiting the person.



If during the course of a long and strenuous EVA astronauts lose several pounds of liquid to sweat and breathing, how does the EVA suit manage all this water? They may have a thermal management system to reduce sweating, but that doesn't solve the breathing issue. I can't imaging they let water/water vapor build up inside the suit, it would make the suit environment extremely uncomfortable.










share|improve this question









$endgroup$














  • $begingroup$
    I’m pretty sure they have a dehumidifier as part of the breathing oxygen loop
    $endgroup$
    – CourageousPotato
    8 hours ago






  • 1




    $begingroup$
    The LCVG included ventilation ducts: en.wikipedia.org/wiki/Liquid_cooling_and_ventilation_garment, en.wikipedia.org/wiki/Primary_life_support_system
    $endgroup$
    – Polygnome
    8 hours ago
















7












7








7





$begingroup$


This answer immediately sparked the question in my mind of how space suits manage water excretion from the person wearing them. I am aware that the astronauts had to wear diapers since one may need to pee during an hours long EVA. However this only manages the liquids exiting the person.



If during the course of a long and strenuous EVA astronauts lose several pounds of liquid to sweat and breathing, how does the EVA suit manage all this water? They may have a thermal management system to reduce sweating, but that doesn't solve the breathing issue. I can't imaging they let water/water vapor build up inside the suit, it would make the suit environment extremely uncomfortable.










share|improve this question









$endgroup$




This answer immediately sparked the question in my mind of how space suits manage water excretion from the person wearing them. I am aware that the astronauts had to wear diapers since one may need to pee during an hours long EVA. However this only manages the liquids exiting the person.



If during the course of a long and strenuous EVA astronauts lose several pounds of liquid to sweat and breathing, how does the EVA suit manage all this water? They may have a thermal management system to reduce sweating, but that doesn't solve the breathing issue. I can't imaging they let water/water vapor build up inside the suit, it would make the suit environment extremely uncomfortable.







spacesuits health eva spacewalk






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked 8 hours ago









QuietghostQuietghost

1,1754 silver badges16 bronze badges




1,1754 silver badges16 bronze badges















  • $begingroup$
    I’m pretty sure they have a dehumidifier as part of the breathing oxygen loop
    $endgroup$
    – CourageousPotato
    8 hours ago






  • 1




    $begingroup$
    The LCVG included ventilation ducts: en.wikipedia.org/wiki/Liquid_cooling_and_ventilation_garment, en.wikipedia.org/wiki/Primary_life_support_system
    $endgroup$
    – Polygnome
    8 hours ago




















  • $begingroup$
    I’m pretty sure they have a dehumidifier as part of the breathing oxygen loop
    $endgroup$
    – CourageousPotato
    8 hours ago






  • 1




    $begingroup$
    The LCVG included ventilation ducts: en.wikipedia.org/wiki/Liquid_cooling_and_ventilation_garment, en.wikipedia.org/wiki/Primary_life_support_system
    $endgroup$
    – Polygnome
    8 hours ago


















$begingroup$
I’m pretty sure they have a dehumidifier as part of the breathing oxygen loop
$endgroup$
– CourageousPotato
8 hours ago




$begingroup$
I’m pretty sure they have a dehumidifier as part of the breathing oxygen loop
$endgroup$
– CourageousPotato
8 hours ago




1




1




$begingroup$
The LCVG included ventilation ducts: en.wikipedia.org/wiki/Liquid_cooling_and_ventilation_garment, en.wikipedia.org/wiki/Primary_life_support_system
$endgroup$
– Polygnome
8 hours ago






$begingroup$
The LCVG included ventilation ducts: en.wikipedia.org/wiki/Liquid_cooling_and_ventilation_garment, en.wikipedia.org/wiki/Primary_life_support_system
$endgroup$
– Polygnome
8 hours ago












2 Answers
2






active

oldest

votes


















7














$begingroup$

The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after each EVA (Extravehicular Activity).



Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/390651main_shuttle_crew_operations_manual.pdf page 2.11-7




The water produced by perspiration and breathing is withdrawn from the oxygen supply by being condensed in the sublimator and is carried by the condensate circuit. The water is then sent to the water - storage tanks of the feedwater circuit and
added to their supply for eventual use in the sublimator. In this manner, the PLSS is able to maintain suit
cooling for a longer period than would be possible
with just the tank’s original water supply.




From Suited for Spacewalking https://www.nasa.gov/pdf/143159main_Suited_for_Spacewalking.pdf



PLSS = Portable Life Support System






share|improve this answer











$endgroup$











  • 1




    $begingroup$
    So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
    $endgroup$
    – Antzi
    1 hour ago










  • $begingroup$
    The EMUs are amazing little spacecraft.
    $endgroup$
    – Organic Marble
    1 hour ago



















1














$begingroup$

I'm sure there are different techniques for different space suits, but here's an example of how it is done for the ISS suits:



The key to handling body heat and sweat is the Liquid Ventilation Garment, or LVC. This is essentially what looks like a full body thermal underwear, but it is lined with tubes that pass water through them. If you heat up, cold water is passed through the tubes, cooling you down. The idea is to keep you cool enough that you don't sweat much.



After the water is heated, it passes through a heat exchanger to cool it down again, then it's recirculated. If necessary, the water can be passed into a sublimator, where it passes though small holes into the vacuum of space, where it sublimates away, carrying heat with it.



If a person does still sweat, the LVC has a wicking layer that will absorb the sweat, and through some mechanism the sweat is collected and added back to the cooling water supply. The problem here is that as you work harder, the temperature of the water in the cooling tubes has to be lower to transport enough heat, which can make it feel cold. Add in a damp undergarment, and astronauts can feel very uncomfortable with this system. Also, you are losing a lot of water to space through the sublimator - maybe a kg of water for a four hour EVA. That's not only expensive, but it limits EVA time.



There is a new LVC being developed for the next gen of suits which will have porous micro-tubules stitched into it that can actually absorb the sweat, the transport it back to the cooling system for recycling. That will allow astronauts to use sweating as their natural heat control.



In the future, mechanical counterpressure suits that don't need to be pressurized will have semi-permeable materials that allow sweat to pass through and sublimate away all across the surface of the suit, which would allow for more passive cooling and a more natural feeling environment.



Link to a paper on the new generation of LVC garments being considered:



Multi-Functional Cooling Garment for Spacesuit Environmental Control



And a paper from 1969 describing the old system for cooling:



Regulation of Thermal Sweating in EVA Space Suits






share|improve this answer










New contributor



Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





$endgroup$











  • 1




    $begingroup$
    The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
    $endgroup$
    – Uwe
    5 hours ago






  • 1




    $begingroup$
    I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
    $endgroup$
    – Dan Hanson
    4 hours ago














Your Answer








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2 Answers
2






active

oldest

votes








2 Answers
2






active

oldest

votes









active

oldest

votes






active

oldest

votes









7














$begingroup$

The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after each EVA (Extravehicular Activity).



Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/390651main_shuttle_crew_operations_manual.pdf page 2.11-7




The water produced by perspiration and breathing is withdrawn from the oxygen supply by being condensed in the sublimator and is carried by the condensate circuit. The water is then sent to the water - storage tanks of the feedwater circuit and
added to their supply for eventual use in the sublimator. In this manner, the PLSS is able to maintain suit
cooling for a longer period than would be possible
with just the tank’s original water supply.




From Suited for Spacewalking https://www.nasa.gov/pdf/143159main_Suited_for_Spacewalking.pdf



PLSS = Portable Life Support System






share|improve this answer











$endgroup$











  • 1




    $begingroup$
    So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
    $endgroup$
    – Antzi
    1 hour ago










  • $begingroup$
    The EMUs are amazing little spacecraft.
    $endgroup$
    – Organic Marble
    1 hour ago
















7














$begingroup$

The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after each EVA (Extravehicular Activity).



Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/390651main_shuttle_crew_operations_manual.pdf page 2.11-7




The water produced by perspiration and breathing is withdrawn from the oxygen supply by being condensed in the sublimator and is carried by the condensate circuit. The water is then sent to the water - storage tanks of the feedwater circuit and
added to their supply for eventual use in the sublimator. In this manner, the PLSS is able to maintain suit
cooling for a longer period than would be possible
with just the tank’s original water supply.




From Suited for Spacewalking https://www.nasa.gov/pdf/143159main_Suited_for_Spacewalking.pdf



PLSS = Portable Life Support System






share|improve this answer











$endgroup$











  • 1




    $begingroup$
    So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
    $endgroup$
    – Antzi
    1 hour ago










  • $begingroup$
    The EMUs are amazing little spacecraft.
    $endgroup$
    – Organic Marble
    1 hour ago














7














7










7







$begingroup$

The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after each EVA (Extravehicular Activity).



Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/390651main_shuttle_crew_operations_manual.pdf page 2.11-7




The water produced by perspiration and breathing is withdrawn from the oxygen supply by being condensed in the sublimator and is carried by the condensate circuit. The water is then sent to the water - storage tanks of the feedwater circuit and
added to their supply for eventual use in the sublimator. In this manner, the PLSS is able to maintain suit
cooling for a longer period than would be possible
with just the tank’s original water supply.




From Suited for Spacewalking https://www.nasa.gov/pdf/143159main_Suited_for_Spacewalking.pdf



PLSS = Portable Life Support System






share|improve this answer











$endgroup$



The shuttle (and ISS) EMU (Extravehicular Mobility Unit) has a condensing heat exchanger as part of its ventilation loop. The condensate is stored, used for cooling, and the excess is drained after each EVA (Extravehicular Activity).



Reference: Shuttle Crew Operations Manual: https://www.nasa.gov/centers/johnson/pdf/390651main_shuttle_crew_operations_manual.pdf page 2.11-7




The water produced by perspiration and breathing is withdrawn from the oxygen supply by being condensed in the sublimator and is carried by the condensate circuit. The water is then sent to the water - storage tanks of the feedwater circuit and
added to their supply for eventual use in the sublimator. In this manner, the PLSS is able to maintain suit
cooling for a longer period than would be possible
with just the tank’s original water supply.




From Suited for Spacewalking https://www.nasa.gov/pdf/143159main_Suited_for_Spacewalking.pdf



PLSS = Portable Life Support System







share|improve this answer














share|improve this answer



share|improve this answer








edited 8 hours ago

























answered 8 hours ago









Organic MarbleOrganic Marble

78k4 gold badges232 silver badges335 bronze badges




78k4 gold badges232 silver badges335 bronze badges











  • 1




    $begingroup$
    So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
    $endgroup$
    – Antzi
    1 hour ago










  • $begingroup$
    The EMUs are amazing little spacecraft.
    $endgroup$
    – Organic Marble
    1 hour ago














  • 1




    $begingroup$
    So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
    $endgroup$
    – Antzi
    1 hour ago










  • $begingroup$
    The EMUs are amazing little spacecraft.
    $endgroup$
    – Organic Marble
    1 hour ago








1




1




$begingroup$
So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
$endgroup$
– Antzi
1 hour ago




$begingroup$
So sweat will cool you off by evaporating in your suit, AND by sublimating out of it... This is beautiful
$endgroup$
– Antzi
1 hour ago












$begingroup$
The EMUs are amazing little spacecraft.
$endgroup$
– Organic Marble
1 hour ago




$begingroup$
The EMUs are amazing little spacecraft.
$endgroup$
– Organic Marble
1 hour ago













1














$begingroup$

I'm sure there are different techniques for different space suits, but here's an example of how it is done for the ISS suits:



The key to handling body heat and sweat is the Liquid Ventilation Garment, or LVC. This is essentially what looks like a full body thermal underwear, but it is lined with tubes that pass water through them. If you heat up, cold water is passed through the tubes, cooling you down. The idea is to keep you cool enough that you don't sweat much.



After the water is heated, it passes through a heat exchanger to cool it down again, then it's recirculated. If necessary, the water can be passed into a sublimator, where it passes though small holes into the vacuum of space, where it sublimates away, carrying heat with it.



If a person does still sweat, the LVC has a wicking layer that will absorb the sweat, and through some mechanism the sweat is collected and added back to the cooling water supply. The problem here is that as you work harder, the temperature of the water in the cooling tubes has to be lower to transport enough heat, which can make it feel cold. Add in a damp undergarment, and astronauts can feel very uncomfortable with this system. Also, you are losing a lot of water to space through the sublimator - maybe a kg of water for a four hour EVA. That's not only expensive, but it limits EVA time.



There is a new LVC being developed for the next gen of suits which will have porous micro-tubules stitched into it that can actually absorb the sweat, the transport it back to the cooling system for recycling. That will allow astronauts to use sweating as their natural heat control.



In the future, mechanical counterpressure suits that don't need to be pressurized will have semi-permeable materials that allow sweat to pass through and sublimate away all across the surface of the suit, which would allow for more passive cooling and a more natural feeling environment.



Link to a paper on the new generation of LVC garments being considered:



Multi-Functional Cooling Garment for Spacesuit Environmental Control



And a paper from 1969 describing the old system for cooling:



Regulation of Thermal Sweating in EVA Space Suits






share|improve this answer










New contributor



Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





$endgroup$











  • 1




    $begingroup$
    The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
    $endgroup$
    – Uwe
    5 hours ago






  • 1




    $begingroup$
    I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
    $endgroup$
    – Dan Hanson
    4 hours ago
















1














$begingroup$

I'm sure there are different techniques for different space suits, but here's an example of how it is done for the ISS suits:



The key to handling body heat and sweat is the Liquid Ventilation Garment, or LVC. This is essentially what looks like a full body thermal underwear, but it is lined with tubes that pass water through them. If you heat up, cold water is passed through the tubes, cooling you down. The idea is to keep you cool enough that you don't sweat much.



After the water is heated, it passes through a heat exchanger to cool it down again, then it's recirculated. If necessary, the water can be passed into a sublimator, where it passes though small holes into the vacuum of space, where it sublimates away, carrying heat with it.



If a person does still sweat, the LVC has a wicking layer that will absorb the sweat, and through some mechanism the sweat is collected and added back to the cooling water supply. The problem here is that as you work harder, the temperature of the water in the cooling tubes has to be lower to transport enough heat, which can make it feel cold. Add in a damp undergarment, and astronauts can feel very uncomfortable with this system. Also, you are losing a lot of water to space through the sublimator - maybe a kg of water for a four hour EVA. That's not only expensive, but it limits EVA time.



There is a new LVC being developed for the next gen of suits which will have porous micro-tubules stitched into it that can actually absorb the sweat, the transport it back to the cooling system for recycling. That will allow astronauts to use sweating as their natural heat control.



In the future, mechanical counterpressure suits that don't need to be pressurized will have semi-permeable materials that allow sweat to pass through and sublimate away all across the surface of the suit, which would allow for more passive cooling and a more natural feeling environment.



Link to a paper on the new generation of LVC garments being considered:



Multi-Functional Cooling Garment for Spacesuit Environmental Control



And a paper from 1969 describing the old system for cooling:



Regulation of Thermal Sweating in EVA Space Suits






share|improve this answer










New contributor



Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





$endgroup$











  • 1




    $begingroup$
    The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
    $endgroup$
    – Uwe
    5 hours ago






  • 1




    $begingroup$
    I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
    $endgroup$
    – Dan Hanson
    4 hours ago














1














1










1







$begingroup$

I'm sure there are different techniques for different space suits, but here's an example of how it is done for the ISS suits:



The key to handling body heat and sweat is the Liquid Ventilation Garment, or LVC. This is essentially what looks like a full body thermal underwear, but it is lined with tubes that pass water through them. If you heat up, cold water is passed through the tubes, cooling you down. The idea is to keep you cool enough that you don't sweat much.



After the water is heated, it passes through a heat exchanger to cool it down again, then it's recirculated. If necessary, the water can be passed into a sublimator, where it passes though small holes into the vacuum of space, where it sublimates away, carrying heat with it.



If a person does still sweat, the LVC has a wicking layer that will absorb the sweat, and through some mechanism the sweat is collected and added back to the cooling water supply. The problem here is that as you work harder, the temperature of the water in the cooling tubes has to be lower to transport enough heat, which can make it feel cold. Add in a damp undergarment, and astronauts can feel very uncomfortable with this system. Also, you are losing a lot of water to space through the sublimator - maybe a kg of water for a four hour EVA. That's not only expensive, but it limits EVA time.



There is a new LVC being developed for the next gen of suits which will have porous micro-tubules stitched into it that can actually absorb the sweat, the transport it back to the cooling system for recycling. That will allow astronauts to use sweating as their natural heat control.



In the future, mechanical counterpressure suits that don't need to be pressurized will have semi-permeable materials that allow sweat to pass through and sublimate away all across the surface of the suit, which would allow for more passive cooling and a more natural feeling environment.



Link to a paper on the new generation of LVC garments being considered:



Multi-Functional Cooling Garment for Spacesuit Environmental Control



And a paper from 1969 describing the old system for cooling:



Regulation of Thermal Sweating in EVA Space Suits






share|improve this answer










New contributor



Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.





$endgroup$



I'm sure there are different techniques for different space suits, but here's an example of how it is done for the ISS suits:



The key to handling body heat and sweat is the Liquid Ventilation Garment, or LVC. This is essentially what looks like a full body thermal underwear, but it is lined with tubes that pass water through them. If you heat up, cold water is passed through the tubes, cooling you down. The idea is to keep you cool enough that you don't sweat much.



After the water is heated, it passes through a heat exchanger to cool it down again, then it's recirculated. If necessary, the water can be passed into a sublimator, where it passes though small holes into the vacuum of space, where it sublimates away, carrying heat with it.



If a person does still sweat, the LVC has a wicking layer that will absorb the sweat, and through some mechanism the sweat is collected and added back to the cooling water supply. The problem here is that as you work harder, the temperature of the water in the cooling tubes has to be lower to transport enough heat, which can make it feel cold. Add in a damp undergarment, and astronauts can feel very uncomfortable with this system. Also, you are losing a lot of water to space through the sublimator - maybe a kg of water for a four hour EVA. That's not only expensive, but it limits EVA time.



There is a new LVC being developed for the next gen of suits which will have porous micro-tubules stitched into it that can actually absorb the sweat, the transport it back to the cooling system for recycling. That will allow astronauts to use sweating as their natural heat control.



In the future, mechanical counterpressure suits that don't need to be pressurized will have semi-permeable materials that allow sweat to pass through and sublimate away all across the surface of the suit, which would allow for more passive cooling and a more natural feeling environment.



Link to a paper on the new generation of LVC garments being considered:



Multi-Functional Cooling Garment for Spacesuit Environmental Control



And a paper from 1969 describing the old system for cooling:



Regulation of Thermal Sweating in EVA Space Suits







share|improve this answer










New contributor



Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.








share|improve this answer



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edited 4 hours ago





















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answered 7 hours ago









Dan HansonDan Hanson

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New contributor



Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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Dan Hanson is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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  • 1




    $begingroup$
    The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
    $endgroup$
    – Uwe
    5 hours ago






  • 1




    $begingroup$
    I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
    $endgroup$
    – Dan Hanson
    4 hours ago














  • 1




    $begingroup$
    The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
    $endgroup$
    – Uwe
    5 hours ago






  • 1




    $begingroup$
    I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
    $endgroup$
    – Dan Hanson
    4 hours ago








1




1




$begingroup$
The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
$endgroup$
– Uwe
5 hours ago




$begingroup$
The sweat with its solved salts is collected and added back to the cooling water supply? But what about the salt in the sublimator and its small holes? These holes should not be blocked by salt crystals.
$endgroup$
– Uwe
5 hours ago




1




1




$begingroup$
I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
$endgroup$
– Dan Hanson
4 hours ago




$begingroup$
I have added a link to the document describing the concept for a new LVC. Note that the sweat is collected as water vapor, so I am assuming that the salts and other impurities would remain on the skin, in the clothing, the liner of the LVC, etc.
$endgroup$
– Dan Hanson
4 hours ago



















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