Final answer:
In case of a large refrigerant leak without access to a self-contained breathing apparatus, vacating and ventilating the area is the recommended action for safety.
Step-by-step explanation:
If a large leak of refrigerant occurs and no self-contained breathing apparatus is available, the best course of action to take is c) Vacate and naturally ventilate the spill area. It's crucial to ensure personal safety first and foremost. Once the area is secure and ventilated, it's safer for trained personnel to use the appropriate protective gear and equipment to locate and stop the leak.
Detailed procedures like using butyl line gloves, leak detectors, or de-energizing the unit and closing service valves should only be conducted by appropriately trained individuals with the required safety equipment. Remember to always follow the manufacturers' instructions when dealing with appliances that release pollutants into the air and ensure a well-ventilated space when dealing with potentially hazardous materials.