Please help answering Scenario Question

Please use chapter 30 unions to answer scenario question must be between 250-400 words.

Scenario 1

You are a supervisor of a nursing unit. You see a “visitor” walking around speaking to your nurses on the floor some seem to speak with him longer than others. You see him seem to get into a passionate debate with one of your nurses. You walk over and hear that they are talking about unionizing.

Questions

What should you do next? Legally what can you do to the visitor?