There are a few differences between the two and it will be helpful to go over the basic ones.
Hazard Severity
Occupational safety involves the safety of the workplace, including personnel safety and individual worker safety concerns that may arise from hazards such as slips and falls.
In contrast, process safety is concerned with preventing extreme safety issues that can arise in facilities that deal with dangerous materials, such as chemicals, gases, and oil. While these facilities also have occupational safety issues, process safety deals with those that arise from major hazards, such as gas leaks, explosions, and uncontrolled fires.
Who Is Protected
Since process safety deals with emergency situations, it protects communities—not only the workers in the facility but anyone in neighboring buildings that could be affected by a destructive event.
Occupational safety, on the other hand, is focused solely on protecting the workers themselves from illness or injury. Occupational safety incidents are far more contained
and localized.
Monitoring
As the name implies, process safety involves ensuring the good functioning of the facility's processes. Depending on the workplace, process safety monitoring might involve regular inspection of chemical release, energy, and contaminant levels to ensure that the hazards remain properly controlled.
Occupational safety monitoring is concerned with the features of the work environment that workers interact with directly. It might include making sure that walkways and stairwells are well maintained and inspecting machine guards to ensure that they are properly installed and in good shape.
Costs
Due to their nature, process safety incidents also occur far less frequently than occupational safety issues. And while it's true that the costs associated with process safety are much higher than those that come with ensuring occupational safety, the costs of not being vigilant about process safety can be astronomical.