Of all personal protective equipment available for the health and safety of workers, respiratory protection may be the most commonly used. It is also one of the most difficult to administer properly. Improper wearing of respirators can have serious consequences. Of 482,000 reported occupational illnesses in 1996, nearly 22,000 of these were attributed to respiratory conditions as a result of inhalation of toxic agents. Providing effective respiratory safety training has generally proven to be challenging, since the protection a respirator provides is dependent on how well the respirator fits the worker's face. Improper donning can lead to serious health consequences and may even be fatal. Training methods are effective if they facilitate workers' progress towards health promoting goals. In this case, proper respirator donning ability is the final exam in determining training method effectiveness. The potential benefit of improving worker health and a review of the OSHA respiratory protection regulations revealed a need for additional investigation about effective respiratory safety training techniques. This study was conducted to investigate the effectiveness of three different training methods (commercial videotape, manufacturer package instructions and a systematic interactive multimedia method). The experiment was divided into two parts. In part one, each training method was examined for its' ability to enable subjects to provide safety information and to identify risks associated with respiratory hazards. Each training technique was also evaluated as function of subject education level, age and gender differences. In terms of safety knowledge and risk perception, results indicated that the systematic interactive multimedia technique was the most effective at training OSHA recommended respiratory safety knowledge, and causing a significant difference between risk perception ratings of worksite conditions determined from a pre- and post- training questionnaire. The systematic interactive multimedia technique incorporated a systematically designed multimedia program with a one-on-one modeled respirator donning technique. Neither manufacturer provided package instructions nor the commercial videotape was significant for safety knowledge or risk perception. Part two of the experiment was the final exam in terms of training effectiveness, where subject ability to achieve passing Quantitative Fit Testing (QFT) after donning half- and full- facepiece negative pressure respirators was evaluated. Training methods were assessed in terms of donning instructions. Additional effects evaluated were respirator presentation order, age, education level and gender differences. Evaluation studies inherently have limitations that affect the interpretation of effects. Quantitative fit testing of respirator masks used in this study could only be conducted on 52 of 72 study participants. Eleven females and nine males were eliminated and were scored as missing values in QFT data analysis due to the constraint imposed by the fact that no available half-facepiece or full-facepiece masks could fit/seal their face shapes. Non-parametric testing indicated the commercial videotape and manufacturers' package instructions were more effective at training subjects to pass half-face respirator quantitative fit testing than full-face respirators. No significant presentation order, age, education level or gender effects were shown. Subjects who could not be tested were petite females and obese males. This finding suggests that a need for additional mask sizes (e.g. extra-small, extra-large) by manufacturers was indicated to reduce the need for custom made to fit masks. In addition, manufacturer's of negative pressure respirators need to be aware of the large number of QFT failures encountered in this study, as well as their causes to improve design. Additional information was obtained in the course of analyzing QFT data. First, a large number of subjects failed quantitative fit testing due to their inability to properly tighten headstraps. All training methods were evaluated for effectiveness in ability to properly convey headstrap tightening. Based on QFT pass/fail results, the systematic interactive multimedia training was shown to be more effective at training headstrap tightening for full-facepiece than half-facepiece respirators, as it resulted in the least number of QFT failures due to improper headstrap tightening. No method was superior to the others at training half-facepiece mask headstrap tightening. / Master of Science

The Aouda.X Space suit simulator, developed by The Austrian Space Forum( OeWF) currently consists of a system that weighs 48 kg of which nearly 57% is comprised of the Suit's HUT (Hard Upper Torso), PLSS (Portable Life Support System) and OBDH (On- board data handling). In addition to this, the current conguration requires 3 hours of assisted donning/doffing. To improve the ergonomics of the design, a relatively lighter HUT/PLSS design prototype with efficient donning capabilities, preferably self -donning, must be developed. This issue can be addressed by proposing a Rear - Entry Design that when implemented on the Aouda.X, can potentially ease these impediments.This study aims at identifying a suitable Rear entry closure design for the current conguration of Aouda.X based on planetary suit performance indicators and operational requirements. The Aouda.X rear entry design is also targeted to be compatible with the NDX -Suitport developed by the University of North Dakota's Human Space Flight Laboratory. The thesis work comprises of the development of a suitable methodology to distinguish a rear entry design for the HUT and PLSS of the spacesuit simulator with the identication of a self-sealing/locking mechanism based on these requirements. A full scale CAD model of the HUT and PLSS with optimal dimensions of compatibility for the Spacesuit with the suitport is designed as a result of this study. Static load bearing analysis is performed to validate the feasibility of the structure and make suitabe recommendations for choice of materials. Methods for further improvement for rear entry suit development are outlined.