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Spacecraft modules that are last purged with clean air several months before they are entered by humans on orbit require careful management. The crew must not be exposed to harmful concentrations of air pollutants when they first enter. The magnitude of the pollution the crew will encounter depends on the volume of the module, the length of time since the last clean-air purge or scrub, the inherent offgassing rate of the materials in the module, the interior temperature of the module while offgassing occurs, and the system leak rate. The time of the last module purge or scrub can be several months before crew entry, so it is essential that the offgassing rate within the module be measured over a suitable interval of time to estimate pollution levels with confidence. Air samples were taken from the STS-74 Russian Docking Module, the STS-79 Spacehab, and the ISS Node 1 prior to launch to predict pollution levels at crew first entry.

The projected radiation levels within the International Space Station (ISS) have been criticized by the Aerospace Safety Advisory Panel in their report to the NASA Administrator. Methods for optimal reconfiguration and augmentation of the ISS shielding are now being developed. The initial steps are to develop reconfigurable and realistic radiation shield models of the ISS modules, develop computational procedures for the highly anisotropic radiation environment, and implement parametric and organizational optimization procedures. The targets of the redesign process are the crew quarters where the astronauts sleep and determining the effects of ISS shadow shielding of an astronaut in a spacesuit. The ISS model as developed will be reconfigurable to follow the ISS. Swapping internal equipment rack assemblies via location mapping tables will be one option for shield optimization.

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.

A description of the largest Acoustic and Vibration Test Facilities in existence for the simulation of major launch vehicle dynamic environment is given and the operational characteristics of both are discussed. Sinusoidal and random excitation techniques are described and unique vibration control methods presented. A comparison of the effects of vibration and acoustic excitation on major space vehicle structures is made.