It is accepted that material handling is an activity presenting a high risk for injury, particularly to the back. In this study, an observation strategy has been developed and validated in order to evaluate the presence of these risky conditions while performing a handling task. Moreover, certain future utilisation conditions were specified. / Fifty-one observation variables were identified and an observation structure was elaborated from three data sources. These sources were: a literature review on observation grids, interviews with expert handlers and video sequences of a laboratory manual handling study where 10 inexperience subjects performed a total of 1500 container transfers. Observational data entry was recorded from a sample of these 174 sequences for which biomechanic measures were also done. / The results show that observations can be reliable and valid and that the diversity of observation objects can be important and extend beyond postural variables. The observations performed on an uninterrupted video sequence are the ones that present the most difficulties. The observers' experience does not seem to be an important factor in obtaining reliable results. On the other hand, the observation criteria, the training and the breakdown of variable classes are factors susceptible to influence reliability. / Many observation variables for balance had a significative impact on the biomechanical measure of balance, particularly when the object is taken and put down. This is the case with the number of foot supports, the weight distribution at the base of support and the position of the object, especially it's lateral deportation with respect to the body. The backward movement of the pelvis, which enables to compensate for the added external weight to the body, was significantly associated to balance. In general grouped variables, have more impact on the measure of balance than variables taken individually. Grouped variables are also less prone to variations when handling contexts are changed. For asymmetry, shoulder orientation with respect to the pelvis, back flexion, parallelism of the shoulders to the ground, and the position of the hands on the object handled all had a significative impact on the effort asymmetries when the object was taken from the plate-form. For the control and fluidity, a difficulty in finding a corresponding biomechanical measure or reliability problems did not enable us to verify whether our observations could have permitted to evaluate the risky conditions. (Abstract shortened by UMI.)
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.36908 |
| Date | January 2001 |
| Creators | Denis, Denys. |
| Contributors | Lortie, Monique (advisor), Rossignol, Michel (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | French |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Occupational Health.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001804001, proquestno: NQ70001, Theses scanned by UMI/ProQuest. |
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