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The purpose of this study was to determine the effect of altered gravity on human jump performance and intermuscular control. A musculoskeletal model was used to determine jump height, muscle power and energy delivered to the skeletal system (jump performance), and changes in muscle neuroexcitation and activation patterns (intermuscular control) for different values of gravity. The different values of gravity ranged from 0.2 to 1.8 times earth gravity. Prior to analyzing the musculoskeletal model solutions, the model solutions were validated by comparing predicted jump heights, time-required-to-jump, ground reaction force, joint kinematics and muscle neuroexcitations to measured experimental data collected in increased gravitational environments. JMD

This report presents an informative, inclusive and concise process which indoor air quality problems can be assessed in the field. It demonstrates the importance of team concepts for investigating problems and performing surveys. A history of indoor air quality is reviewed, including survey results by the indoor air quality survey team from Armstrong Laboratory. Recommendations are made that will improve the quality and efficiency of field investigations., Supercedes rept. no. USAFOEHL-87-037.

Respirators are worn in industry and Armed Forces to reduce the inhalation of contaminants. These contaminants include vapors, gases and aerosols. The best protection, generally, is provided by a full-face piece respirator. Frequently, however a negative pressure half-face respirator of choice for lower costs, less burden on the user and less visual obstruction. This type of respirator covers the face from the bridge of the nose to underneath the chin. When the user inspires, a negative pressure is produced in the respirator cavity pulling air through the filters. Any contamination entering the respirator cavity, resulting in the user's exposure to this contaminant, is due to failure of either the filter or the face seal. In the half-face, negative pressure respirator, with replaceable filters, the incomplete face seal is generally the major cause of leakage. To determine the amount of leakage into the respirator cavity, several test methods have been developed. These methods can be categorized into two types, qualitative and quantitative fit test methods.

The Wilford Hall USAF Medical Center Central Processing Section (WHMC/SGLP) uses ethylene oxide (EtO) as a primary sterilizing agent. Because of their concern about the health effects of EtO), SGLP has searched for a continuous monitoring EtO system. In their search, they found two units (AMSCO's Envirogard III and Baseline Industries, Inc.'s Model 5500 Gas Analyzer). The objective of this evaluation was to conduct a field study to compare the performances of the two direct-reading continuous EtO monitors against the Occupational Safety and Health Administration's (OSHA) acceptable charcoal tube sampling method. In addition, the 3M EtO passive monitor sampling method was compared with the charcoal tube method and direct-reading instrumental method as well. Neither the Baseline Industries, Inc. nor the AMSCO continuous monitors corresponded to OSHA acceptable charcoal tube method of air sampling. Both instruments reported EtO concentrations much higher than those detected by the charcoal tubes. There is no way of knowing which method, the direct-reading continuous monitor or the charcoal tube/passive monitor, is more correct. However, the OSHA standard for EtO is based on measuring EtO by the charcoal tube method. Keywords: Air pollution, Industrial medicine.