Complex industrial systems are increasingly software driven, rapidly evolving into autonomous, self-adaptive processing at industrial field. Artificial intelligence technologies are spreading fast at industrial Edge, improving the industrial operations efficiency. However Edge computing systems involving artificial intelligence must also continuously ensure the safe operations. This paper assesses the state of the art of cognitive technologies with their relevance for artificial intelligence implementation at industrial safety critical systems. It introduces then a state of the art for artificial intelligence safety assurance practices. Implementation at the industrial application stack is illustrated with the edge virtual operating system that operates the industrial fog. Edge operating system is evolving fast as kind of an AI intensive software. Industrial developments are illustrated with Slap OS, real case examples of swarm computing and advanced robotic.