Which form specifies the criteria for inspecting vehicles used to transport ammunition?

The correct form that specifies the criteria for inspecting vehicles used to transport ammunition is the DD Form 626. This form is particularly important as it is designed for the inspection of vehicles when they are utilized for the transport of hazardous materials, including ammunition. It details the specific requirements and safety standards that must be met to ensure the safe transport of these materials, thereby mitigating risks associated with handling and transportation.

The significance of the DD Form 626 lies in its focus on evaluating various aspects of the vehicle, such as its capability to carry explosives safely, compliance with safety regulations, and operational readiness. By outlining specific criteria, it provides a comprehensive checklist that must be adhered to before transportation occurs, ensuring that all safety and regulatory standards are maintained throughout the process.

Other forms listed serve different purposes. For instance, DA Form 581 is used for requisitioning ammunition, DA Form 3151-R records ammunition transactions, and DA Form 1687 is related to the appointment of custodians of military property. These forms do not address vehicle inspection for the transportation of ammunition, which is why they are not relevant to this question.