How Safe is Our Nurse Call System?

System Theoretic Process Analysis(STPA) is a hazard or risk analysis method based on systems thinking, with a top down approach. It focuses the attention on problems that may end up as accidents. We used STPA to assess the hazards of our nurse call system. The analysis resulted in 37 unique safety constraints. For safety to emerge, each of the 37 safety constraints should be enforced. To our judgment eight (22%) of these are consistently applied. The other 29 (78%) are not, or in some cases cannot be enforced.