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This report presents the results of the driver's field of view and the performance of six crossview and two sideview mirror systems on a conventional long-nosed school bus. It also contains an evaluation of the image quality of the crossview mirrors in terms of the angular length and width of their reflected images. The measurements of the field of view and the evaluation of image quality were done at two driver eye locations, one representative of the cyclopian view of a 95th percentile adult male and the other one representative of the cyclopian view of a 5th percentile adult female. Measurements were taken considering that there were no head movements. For the purposes of the study, the term “blind spot” was defined as meaning any area that could not be seen directly by the driver. The performance of the mirrors was judged in terms of their capacity to provide a complete and clear view of the blind spots.

This paper reports the results of a study to determine the effects of a top tether strap on the performance of child restraint systems (CRS). Four commercially available CRSs and the CanFIX were tested. All restraints tested had a similar design T-shield type harness system to minimize harness variability. As part of the test matrix, tether webbing, tether height and tether slack were varied. The dummies used for testing were the 12-and 18-month CRABI. Head and chest acceleration, head excursion, upper and lower neck loads and resultant moments were recorded. Although the presence of slack in the tether strap degrades the performance of the CRS, a tether strap with slack present improved the response of a dummy restrained in a CRS when compared to an identical tetherless restraint. With maximum slack, the results for the restraint condition approached results from a tetherless condition while still demonstrating a slight benefit.

This report presents results from a performance evaluation study on the adequacy of the image size, within school bus cross view mirrors, mandated by FMVSS 111 The mandated image size is 9X3 minutes of arc (ie, 9′X3′) Six observers discriminated the orientation offset of three different image sizes (ie, 45′X15′, 9′X3′, 13.5′X45′) presented onto a banana type cross view mirror. The images were presented to observers under three luminance contrast levels 15%, 20%, and 25%. Results indicated that poor performance was associated with the 45′X15′ image size at all contrast levels and the 9′X3′ image size at a luminance contrast of 15%. The 135′X45′ image size was associated with good performance. In conclusion, measures of performance failed to demonstrate an unequivocal deficiency of the 9′X3′ image size.