Workflow is the basic need of every business so thus it is also applicable to EHS domain.
The EH&S workflow automates the editing of value assignment types. The collective term EH&S workflow groups together a series of tools that offer you support with creating workflow definitions within the SAP Environment, Health and Safety (EH&S) component.
One more permit approval is a business process which will be handled through PM (Plant maintenence ) module using WCM (Work clearance mgmt) concept
There is also Incident Workflows and Tasks.
As far as workflows in EH&S are concerned you can create them whenever you want to generate same sequence of activities for repetitive requests. i.e Whenever new material is created you can create workflow triggered to Product safety person who can create specification