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This study is part of an on-going series of studies that relate to Alpine or Downhill Ski Boot Design. In current Alpine skiing, the ski boot is an integral part of the ski boot-binding system. One of the roles of the ski boot is to protect the ankle from excessive dorsiflexion during forward falls, as the ski boot is levered out of the heel binding. A boot designer needs to know what the ranges of dorsiflexion are for human ankles so that the allowable forward flex built into the ski boot will not exceed some specified level. That specified level should be such that a large part of the population will not exceed a safe level of dorsiflexion. The stiffening of the ankle by voluntary contraction of the muscles that control the ankle joint cannot be relied upon since the reaction time to contract the muscles will be greater than the time available to the skier under many circumstances. This study looks at the maximum voluntary dorsiflexion of a group of people (n=64) similar to a skiing population. The anatomical and biomechanical posture of the subjects was intended to represent typical skiing situations, therefore the subjects were measured in a weight bearing, flexed knee, upright posture. The age, gender, height, weight and skiing experience of the subjects was recorded as independent variables. The maximum voluntary dorsiflexion of the ankle was the dependent variable. 10 subjects were measured while the knee was kept in a straight or extended posture. The analysis indicates that there is no statistically significant relationship between dorsiflexion and any of the independent variables. The mean dorsiflexion was 42.7 degrees, the 5th% value was 28.5 and the 95th% was 56.7 degrees. The straight knee posture reduces the effective dorsiflexion by 8.5 degrees. Current standards permit as much as 40 to 45 degrees dorsiflexion. The implications are that current standards are excessive, a reasonable limit would be something under 30 degrees. Such a limit, or less, is consistent with the maximum dorsiflexion found in most current ski boots.

The author spent two months as a Faculty member participating in a faculty exchange program in the People's Republic of China. While there, he taught an undergraduate course in Human Factors Engineering in Machine and Workplace design. He also conducted a week long seminar for factory engineering personnel and engineering faculty on the same topics. He consulted with industry and traveled extensively in China during this time. This paper is based on his experiences and observations. Specific topics are: 1) quality and nature of students in the PRC vs. the US, Japan and Europe; 2) Programs in Human Factors in the PRC; 3) Academic Engineering Laboratories in the PRC and 4) Safety Engineering in the PRC.

This paper is an overview of a series of laboratory procedures and exercises used to demonstrate basic human factors principles to the undergraduate student. The basic topics covered are presented along with a description of a few of the laboratory exercises available. For each exercise, a brief description of the objective, methodology and data analysis is included with a discussion of any special hardware or software requirements. Additional laboratory aids discussed include hardware, software and teaching aids.

This research involves the generation of standards for release bindings used in downhill or “Alpine” skiing. The American Society for Testing and Materials (ASTM) is currently working on voluntary consensus standards for the manufacture of skiing equipment. One aspect under investigation is the effect of specific environments (vibration, contamination and corrosion) on the stability of the functional release characteristics of bindings.The results of the current research indicate that vibration tests affect bindings that have threaded fasteners without any locking provision. The dust and dirt tests affect bindings that rely on a moving boot-binding interface more than those that don't. The salt-fog exposure affected all metallic surfaces. Cast aluminum surfaces were more affected than forged, rolled or drawn surfaces. Stainless steel was relatively unaffected. Bearing surface deterioration was the major factor. Some interaction with boot-binding interfaces did occur. Limits are suggested that differentiate between high and low quality bindings.

The objective of the study was to predict relative accident rates as a function of a two-factor risk-taking model (need for achievement and locus of control). At the same time, the effect of situation-specificity was tested. The subjects were performing the skilled task of Alpine (down-hill) skiing. There were 67 control and 50 injury subjects in all. The 67 controls took a series of three tests (Atkinson's need for Achievement (n Ach), Rotter's Locus of Control (LC) and an experimental instrument called the Situation-Specific Test (SST). The median score on each test was used as the cutting score. Those scoring above the median were scored high, those below were scored as low. Based on the underlying theory it was predicted that the accident/injury group would score high on the LC and SST and would have extreme scores (very high or very low) on n Ach. An interaction between n Ach and LC or SST was predicted. The results indicated that for real-world situations, situation-specific tests are more discriminating than are standardized, non-specific tests. No statistically significant effect for either standard test or the interaction was found. A statistically significant effect was found for SST. The results suggest methodological approaches that may shed light on risk-taking assessment with accident prediction potential in other areas. A successful instrument for discriminating potential accident victims from the population at large was demonstrated. The opportunities for application in other areas of skilled task performance such as industrial jobs and automobile driving are currently being investigated.

This is a clinical analysis of XC and DH injuries reported thru the CPSC NEISS data files. It suggests that there are significant differences between the two sports and that there are occasionally significant interactions with gender as well. There are some implications with regard to injury mechanisms as well as hardware factors. In order to more fully understand and interpret these findings, it will be necessary to couple these findings with an examination of the populations at risk in a quasi-epidemiological methodology.

Paper shows how the belief that one has about how accidents happen (Theory of Accident Causation) affects the design of the Accident Report Form, the type of information gathered, the nature of your accident data base, the analysis of the data and, finally, the way in which you intervene in the situation. Two different approaches are examined, one which is typical of most existing systems, the other represents a much improved system that points the way to more effective intervention strategies.