Which index designation would require a minimum of 1,500 gallons of water for foam production?

The index designation that necessitates a minimum of 1,500 gallons of water for foam production is associated with more significant fire risks and larger aircraft. This classification takes into account the potential hazard posed by the aircraft type and the complexity of handling fires that may arise from different fuel types.

Index B specifically addresses the requirements for foam application and recognizes that a substantial volume of water is essential to create an effective foam blanket necessary for extinguishing larger fires, particularly those that could be fueled by aviation fuels.

In contrast, other index designations, such as A, C, and D, would call for lesser amounts of water, reflecting the nature of the hazards related to those classifications. This systematic approach to designating water requirements for foam production enables airport fire departments to allocate resources more efficiently and ensure a rapid response to varied fire scenarios associated with different aircraft sizes and fuel types.