In every industry, people or employees are exposed to different kinds of hazards. These harm their body, health, the surroundings, etc. Hierarchy of hazard control is a system that would allow industry to minimize or not eliminate these hazards.
In the hierarchy, what comes before the PPE are the Engineering Controls, which ensures that the design is suited for the purpose, and, Administrative Controls, in which people should be taught on how work should be done and the underlying safety principles.