Accession Number:

ADA151218

Title:

A Theoretical Method for Selecting Spacecraft and Spacesuit Atmospheres,

Descriptive Note:

Corporate Author:

DUKE UNIV MEDICAL CENTER DURHAM NC

Personal Author(s):

• Vann, R. D.
• Torre-Bueno, J. R.

Report Date:

1984-12-01

Pagination or Media Count:

6.0

Abstract:

A theoretical method for selecting space craft and space suit atmospheres assumes that gas bubbles cause decompression sickness and that risk increases when a critical bubble volume is exceeded. The method is consistent with empirical bubble volume is exceeded. This method is consistent with empirical decompression exposures for humans under conditions of nitrogen equilibrium between the lungs and tissues. Space station atmospheres are selected so that flight crews may decompress immediately from sea level to station pressure without preoxygenation. Bubbles form as a result of this decompression but are less than the critical volume. The bubbles are absorbed during equilibration period after which immediate transition to suit pressure is possible. Exercise after decompression and incomplete nitrogen equilibrium are shown to increase bubble size, and limit the usefulness of one previously tested stage decompression procedure for the shuttle. The method might be helpful for evaluating decompression procedures before testing.

Descriptors:

• *BREATHING GASES
• *CONTROLLED ATMOSPHERES
• *DECOMPRESSION
• BIOLOGICAL ABSORPTION
• BUBBLES
• DECOMPRESSION SICKNESS
• EQUILIBRIUM(GENERAL)
• EXERCISE(PHYSIOLOGY)
• FLIGHT CREWS
• GASES
• HUMANS
• LUNG
• NITROGEN
• PRESSURE SUITS
• REPRINTS
• RISK
• SIZES(DIMENSIONS)
• SPACE CREWS
• SPACE FLIGHT
• SPACE STATIONS
• SPACECRAFT
• THEORY
• TRANSITIONS
• VOLUME

Subject Categories:

• Life Support Systems

Distribution Statement:

APPROVED FOR PUBLIC RELEASE