To find the durability requirements for polycarbonate visors on flight helmets, which resource is necessary?

The durability requirements for polycarbonate visors on flight helmets are governed by military specifications. A military specification details the essential technical requirements for products, which includes performance and durability criteria. It ensures that the materials used, such as polycarbonate, meet the necessary standards for safety and effectiveness in military operations.

In contrast, military standards typically focus more on measuring and establishing practices and processes rather than specific product specifications. Administrative instructions generally deal with procedural guidance rather than material specifications. Technical manuals, while they may provide operational guidance and maintenance instructions for equipment, do not usually contain the detailed specifications needed for material properties and performance standards. Therefore, to determine the precise durability requirements for flight helmet visors made from polycarbonate, a military specification is the most pertinent resource.