...doors will be designed to resist intrusion by a person who attempts to enter using physical force. This includes the door, its means of attachment to the surrounding structure, and the attachment structure on the bulkhead itself. The FAA rule uses an impact standard that is 50 percent higher than the standard developed by the National Institute of Law Enforcement and Criminal Justice. In addition to intrusion protection, the FAA is using a standard sufficient to minimize penetration of shrapnel from small arms fire or a fragmentation device.