Final answer:
The question is about protecting non-metallic pipe and tubing in fire sprinkler systems with a material of a minimum fire rating. The specific number of minutes would depend on building codes and regulations.
Step-by-step explanation:
The question is pertaining to the protection measures required for non-metallic pipe and tubing in fire sprinkler systems.
The requirement is for these pipes and tubing to be protected from exposure to the occupied space by a material with a minimum fire rating of a certain number of minutes. In other words, the material used to protect the pipes and tubing should be able to withstand fire for a specified period of time.
The specific number of minutes is not mentioned in the question and would depend on the applicable building codes and regulations of a particular jurisdiction.