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A work envelope has been defined for weightless Extravehicular Activity (EVA) based on the Space Shuttle Extravehicular Mobility Unit (EMU), but there is no equivalent for planetary operations. The weightless work envelope is essential for planning all EVA tasks because it determines the location of removable parts, making sure they are within reach and visibility of the suited crew member. In addition, using the envelope positions the structural hard points for foot restraints that allow placing both hands on the job and provides a load path for reacting forces. EVA operations are always constrained by time. Tasks are carefully planned to ensure the crew has enough breathing oxygen, cooling water, and battery power. Planning first involves computers using a virtual work envelope to model tasks, next suited crew members in a simulated environment refine the tasks.

In order to estimate the exposure to a crew in space, there are three essential steps to be performed: first, the ambient radiation environment at the vehicle must be characterized; second, the mass distribution properties of the vehicle, including the crewmembers themselves must be developed, and third a model of the interactions of space radiations with matter must be employed in order to characterize the radiation field at the dose point of interest. The Space Radiation Analysis Group (SRAG) at the NASA, Johnson Space Center carries the primary responsibility for the operational radiation protection support function associated with manned space flight. In order to provide support during the various planning, execution, and analysis/recording phase activities associated with a given mission, tools have been developed to allow rapid, repeatable calculations of exposure on orbit.

Comments of the Space Shuttle crew indicate that the Launch Entry Suit (LES) may provide inadequate cooling before launch and after reentry. During these periods some crewmembers experienced thermal discomfort induced by localized cabin heating, middeck experiments, and crewmembers' body heat and humidity. The NASA Johnson Space Center(JSC) Crew and Thermal System Division (CTSD) executed a two phase study, analysis and testing, to investigate this problem. The analysis phase used a computer model of the LES to study the transient heat dissipation and temperature response under the various Space Shuttle flight cabin environments. After the completion of the analysis, the testing phase was conducted to collect the engineering data in order to validate the analysis results. Due to the constraint of the test facility, the test was conducted on the air cooled techniques only. This paper presents the analytical model, its solution and an evaluation and summary of the test results.

The Crew and Thermal Systems Division (CTSD) at NASA's Johnson Space Center under the support of the Office of Life and Microgravity Sciences and Applications is conducting the Early Human Testing Initiave (EHTI) project with the goal of validating regenerative life support technologies through a series of integrated tests with human subjects. The EHTI project is organized into three distinct phases, each with progressively more complex integration of biological and physicochemical (P/C) life support technologies. The goal of Phase I is to conduct a 15-day one-person test to verify the performance of an air revitalization system based on higher plants with physicochemical systems as complements and backups. The test will be performed in CTSD's Variable Pressure Growth Chamber (VPGC), a tightly closed controlled-environment test chamber configured with approximately 11 m2 of area for plant growth.

An advanced development helmet mounted display (HMD) was designed and fabricated under NASA-Johnson Space Center (NASA/JSC) contract, NAS 9-17543, by Hamilton Standard Division of United Technologies, Windsor Locks, CT. The work was initiated in December 1985 and culminated in June 1988 with the delivery of an extravehicular mobility unit (EMU) HMD demonstration unit as an alternative to the current low-resolution, chest-mounted display and cuff-mounted checklists. Important design goals achieved with this HMD include the use of transmissive liquid crystal display (LCD) image sources with fairly high resolution (i.e., text, graphics, and video compatible), binocular viewing with total image overlap, virtual image projection, low profile packaging, low power design, and demonstration of voice control of the HMD data.

Typical calculations of radiation exposures in space approximate the composition of the human body by a single material, typically Aluminum or water. A further approximation is made with regard to body size by using a single anatomical model to represent people of all sizes. A comparison of calculations of organ dose and dose-equivalent is presented. Calculations are first performed approximating body materials by water equivalent thickness', and then using a more accurate representation of materials present in the body. In each case of material representation, a further comparison is presented of calculations performed modeling people of different sizes.