Customer-facing roles
Dealing with members of the public creates a certain level of risk because of the unpredictability of people. The majority of the time, these people are complete strangers and you have no background history on their personality or state of mind.
The hospitality and retail sectors are prime examples where workers face increased risk, particularly if they are serving members of the public under the influence of alcohol or selling age-restricted items.
The level of risk should be elevated again if at any point staff are lone working, for example behind a bar on a quiet night or in a local convenience store.