Some things need to happen at a specific time, not just at some point during the shift — a scheduled reminder makes sure they are not forgotten.
Create a reminder with a specific time (or a recurring schedule) and a message describing what needs to happen. Target it at specific departments, so only the people it is actually relevant to see it.
When the scheduled time arrives, the reminder appears as a popup for everyone in the targeted department who is logged in. It stays visible until dismissed, and dismissing it is a deliberate action.