Come up with around 8-12 questions for each are: Confined Space, Fall Protection, Safety Signs & Tags, and Hand Tools. You also have to come up with around the same amount of questions for your non-reg topics: Drug Testing and Incident investigation.
You need to make these 8-12 questions for All topics in these areas of the audit: Facility inspection, documentation review and Employee interview questions (3 are mandatory for this category). And this is 8-12 combined, NOT 8-12 for each category of the audit.
The best advice for the regulated topics you have been assigned is to look at OSHAs general industry regulations and use them as a guide to make those questions. For the non-reg topics, use google to help you find possible audit questions.
Important note: Each question has to have a review answer means each one tell you how to get high score and the grade from 1 to 10 how to get 10/10 (review criteria to be used by the HR).