This paper analyzes the emergence of the Occupational Safety and Health Act of 1970 and finds previous explanations of its origin inadequate. I trace the roots of this law to the protests of rank-and-file workers across the United States at a time when the support of these workers was particularly important to the two main political parties. The protest was directed not only at those employers who operated unsafe and unhealthy workplaces, but also at union officials who paid little or no attention to safety and health issues in negotiating new contracts
