Recurrent incident reports indicate that ground operators have not always performed the right action or made the right decision following maintenance operations of transport systems. This paper explores first the physical-physiological requirements for a human to perceive right the meaning of symbolic properties technical objects afford when they are being maintained in variable contextualized situations. This paper explores then the impact of these necessary but not sufficient Human Factors requirements on the specification process of a maintenance enabling system by prototyping a door latchlock case-study with a modeling environment based on SysML.