Safety requirements modeling based on RUCM

Safety requirements have commanded increasing attention as software is playing a more and more important role in today´s safety critical systems. As many experts, scholars have found that the main reason for safety critical systems´ accident is bad requirements which means inaccurate, incomplete or inconsistent requirements may lead to misunderstanding of the system and may cause a fault in software design and realization, and brought disaster to people or environment. The main reason of bad requirements is poor communication between safety engineers and requirements analysis engineers. Safety requirements essentially are requirements to protect the software system go into a danger state which will cause lost of life or asset or environment damage. Safety requirements deal with errors, faults that the system may come across. So In this paper, we combine fault protection concepts with safety requirements, and propose a model-based safety requirements modeling approach named Safety RUCM to describe safety requirements in order to reduce inaccurate, incomplete or inconsistent safety requirements and at the same time to enhance mutual understanding on safety requirements between safety.