What were the precautions taken for Derek's safety in the hill scene?

2017-12-14 10:31:19

In Peter Jackson's 1987 film, Bad Taste, one of the main characters, Derek, is fighting with aliens on the side of a rather steep hill. I have to wonder what kind of safety precautions the actors took when filming this scene so as to not trip and fall to their death. I can't imagine it was anything all that special knowing most of the props and such were made by Jackson himself and that the movie was very low budget.

I was not able to find anything online talking about how this scene was filmed.