NAIT tags that can't be read with an RFID reader 

If an animal is tagged with a NAIT device that cannot be read by an RFID reader, the tag must be read visually and recorded in a ‘kill upload’ file in the NAIT system, with the visual ID tag number. 

Missing tags 

If an animal arrives without a tag and has not been declared as unsafe to tag by the sending PICA, it must be notified to the NAIT organisation as an untagged kill using the ‘kill upload’ function.