Final answer:
According to USP 797, the first personal protective equipment to be applied during aseptic technique is the gown, followed by gloves.
Step-by-step explanation:
According to USP 797 guidelines for aseptic technique, the personal protective equipment (PPE) that should be applied first is the gown. The purpose of the gown is to protect the healthcare worker's clothing and skin from contamination. After putting on the gown, the healthcare worker should proceed to put on gloves, which provide a barrier between the hands and any potentially infectious materials.