Under what condition can fire proof gash bags be used?

The use of fireproof gash bags is specifically mandated for safety reasons when dealing with waste disposal in an aircraft environment. The correct condition for using fireproof gash bags is when both gash carts in the forward and rear galleys are completely full. This is because the fireproof bags are designed to contain any potential fire hazards that may arise from the disposal of hazardous materials or items, such as hot food waste or certain types of packaging, which may pose risks when left in regular waste containers.

When both carts are full, it indicates that there is a significant accumulation of waste which increases the risk of fire. By using the fireproof gash bags at this point, it ensures that if a fire does start from the waste, it can be contained effectively, reducing the risk of it spreading within the aircraft. In contrast, situations like having one gash cart full, both carts empty, or when in-flight service is completed do not present the same immediate need for the enhanced safety measures provided by fireproof gash bags. They do not indicate a heightened risk of fire that would justify the use of these specialized bags.