ISO 9001:2015 is not about standardization of office documents. It is about the standardization of all documents relevant to the quality management system. It is not mandatory to apply the same standardization to occupational safety. However, I advise doing that. Later, if the organization wants to integrate together quality and occupational safety in the same management system, there is a common set of rules for document standardization.
You can find more information about document control below: