I have no specific examples from the chlor alkali chemical industry.
When I work with an organization that wants to implement the risk-based approach I consider three sources to determine risks:
In chemical and process industries I start with something familiar to most of their people, drawing a process flowchart and asking what are the expect results or undesirable consequences of operating each process. Then I ask what can go wrong and go against getting the expected results or promoting the undesirable consequences. I do not focus only on the work-in-process but also on equipment and instrumentation functioning and warehousing conditions. Then I work in determining risks around products and services. What can go wrong with the product or service or its use by the customer or other interested party. Finally, through the use of a PESTLE analysis we determine internal and external issues and determine possible risks. This kind of risks most of the time are from a more abstract or strategic level.
The following material will provide you more information about the risk based approach: