As a Business Operations Manager how would you go about training you staff who understands minimal English with regards to Food Safety and OHS?

You can use non-verbal communication.

This is good query, we have similar situation while conducting awareness session at our plant floor. The labor couldn't understand the English well and we translate the maximum of material in regional or local language. We pay special attention and add graphics, image and used vocal tones to emphasize our message. I believe language is not a big issue we could train the team and bring them up to certain level if we customize our material. Rest, best of luck!

I would be addressing this situation by customizing the training materials in to a medium with the focus on their easier understanding and recognition. Instead of taking them for a vocal briefing in training rooms, I would prefer to take them to practical labs where in I can train them with live demonstrations and create the  best situations to explain the do's and don'ts.

There are many trainers or training centers that can train your staff , its a matter of outsourcing a trainer. 

Request to training organizer to hire trainer who knows local language of your staff.

of course YES, this is the best solution , other wise you have to translate & translate & translate a lot of things, and the translation processes  NEVER  will not be stopped 

This is important aspect in a company where multilingual staff is working. For me I will go for visual aids to make them better understand.