When do Freelance Instructors need their own Public Liability Insurance?

We are frequently asked at this time when do freelance instructors need their own personal public liability insurance? 

Activity providers frequently ask ;- "when do freelance instructors need their own personal public liability (PPL) insurance?  Responsibility for risk, control, and liability can shift depending on how the instructor is engaged and who is delivering the activity. In practice, it’s about protecting the organisation, the instructor, and the client if something goes wrong.

The document below iprovides guidance and helps to define the two differences.