L’ergonomie et la réglementation de la prévention des lésions professionnelles en Amérique du Nord

Cet article examine la réglementation adoptée par cinq administrations publiques en Amérique du Nord qui ont choisi de faire appel à la science de l’ergonomie comme outil réglementaire de prévention des troubles musculo-squelettiques (TMS). Aux États-Unis, seul le règlement de la Californie, d’une portée fort limitée, a pu survivre aux pressions politiques qui ont mené à l’abrogation des règlements de l’État fédéral américain (OSHA) et de l’État de Washington. Au Canada, la Colombie-Britannique et la Saskatchewan appliquent de tels règlements, mais contrairement aux instruments américains abrogés, ceux du Canada misent plutôt sur le processus de prise en charge que sur des normes spécifiques qui quantifient les gestes à risque et déterminent de façon stricte les actions attendues de l’employeur. La description du contexte d’adoption et du contenu des règlements est ensuite suivie d’une comparaison sommaire de cette réglementation avec le droit québécois régissant la prévention des TMS.This article examines five ergonomic standards adopted by regulatory agencies in North America for the purpose of preventing musculo-skeletal disorders (MSDs), one of the most costly categories of injury throughout North America. Since 1988, three regulatory agencies in the United States and two in Canada have chosen to implement “ergonomic standards”, relying on knowledge produced by the science of ergonomy to prevent injury associated with various risk factors known to contribute to MSDs. Saskatchewan was the first to regulate the prevention of MSDs in 1988, followed by California (1997), British Columbia (1998), Washington State (2000) and OSHA (2001). While the first three regulations are still in force, political pressure by business lobbies led to the repeal of both the OSHA regulation, repealed shortly after the Bush cabinet came to power, only weeks after its adoption, and the Washington State regulation, repealed as a result of a referendum in late 2003.The article first situates ergonomic standards in the historical context of occupational health and safety regulation. Gunningham and Johnstone (Regulating Workplace Safety: Systems and Sanctions, Oxford University Press, 1999), in a historical overview of regulatory strategies in occupational health and safety, show that, in many Anglo-Saxon jurisdictions, the traditional approach of command and control regulation, based on a multitude of technical specifications, has evolved into a performance based approach, relying on general duty clauses and codes of practice while placing less reliance on technical specifications. The third and most recent regulatory approach, relying on process regulation and occupational health and safety management systems, has developed considerably in Europe but has not yet taken hold in most North American jurisdictions.The historical overview allows us to consider why the various ergonomic standards studied have led to so much controversy, particularly in the United States, as tensions arose as those who preferred stringent regulation of ergonomic hazards met with very strong resistance from business interests, many of whom were determined to prevent any form of regulation relying on ergonomy. The nature and outcomes of the political confrontation in the different jurisdictions are then examined.The article then describes the regulatory framework of each of the five standards studied. The most timid is that of California, targeting only the prevention of “repetitive motion injuries”, constraining the employer only after at least two workers are injured in the same job, and presuming employer response to be adequate. All the other regulations are broader in scope, aiming to prevent all forms of musculo-skeletal disorders, ensuring that all employers undertake some form of risk assessment and providing, in different ways, specific tools to facilitate detection of hazardous working conditions. OSHA and Washington State regulations rely on a quantitative approach, specifying in detail different forms of ergonomic risks. The Canadian regulations are more process based, ensuring that employers do a risk assessment and relying on training and the provision of information to workers and unions without prescribing a quantified standard, but only the procedures to be followed. Tables show the different steps to be followed under each regulation (Table 1) and the different risk factors to be examined (Table 2).An examination of the role reserved for different actors in the prevention process (Table 3) shows that ergonomists themselves are not specifically named in any of the regulations. The designation of these standards as “ergonomic” is based on their reliance on knowledge gleaned from the study of ergonomy, yet the fact that these North American regulations only look to prevent MSDs shows that many other teachings of ergonomy are completely overlooked.After describing the five regulatory instruments that rely explicitly on ergonomy, the article examines the situation in Quebec. The Occupational health and safety regulation contains a few specific obligations that have existed for years, including the obligation to provide chairs, when feasible, and a few conditions applicable to manual handling and the placement of tools. The Quebec inspectorate of the Commission de la santé et de la sécurité du travail (CSST) also relies on the general duty clause to implement change in the workplace with regards to ergonomy. It is unclear whether this approach has met with success, and a few administrative tribunal judgments lead us to believe that an ergonomic standard would ensure a more flexible approach that would encourage employers, unions and workers to act promptly to implement strategies designed to prevent MSDs. An ergonomic standard would also facilitate the work of inspectors while allowing them to encourage the employer to undertake risk assessments and prevention programmes.In conclusion, a number of issues are raised concerning the appropriate regulatory approach that will ensure the prevention of MSDs and also introduce an ergonomic approach to occupational health and safety prevention strategies. Critics suggest that an approach based only on specifications will never adequately prevent MSDs, as the variability of individual morphology escapes quantification. Others suggest that without specifications, enforcement becomes impracticable. The American experience, as compared to the Canadian, leads us to conclude that a more harmonious regulatory process is necessary to guarantee the efficacy, and the survival of ergonomic standards.Este artículo examina la reglamentación adoptada por cinco administraciones públicas en América del Norte que han escogido de se servir de la ciencia de la ergonomía como instrumento reglamentario de prevención de los disturbios músculo-esqueléticos (DME). En los Estados-Unidos, solo el reglamento de California, de ámbito muy limitado, ha podido sobrevivir a las presiones políticas que han llevado a la abrogación de los reglamentos del Estado federal americano (OSHA) y del Estado de Washington. En Canadá, la Colombia Británica y la Saskatchewan aplican tales reglamentos, pero contrariamente a los instrumentos americanos abrogados, los de Canadá reposan mas bien en el proceso de responsabilización que en las normas especificas que cuantifican los gestos a riesgo y determinan de manera estricta las acciones previstas por el empleador. La descripción del contexto de adopción y del contenido de los reglamentos es seguida de una comparación somera de dicha reglamentación con el derecho quebequense que rige la prevención de DME