Hazard Evaluation Methodology for Computer-Controlled Mine Monitoring/Control Systems

A summary of results of the development of a methodology for identifying safety hazards inherent in underground monitoring and control equipment will be given. Under a US Bureau of Mines contract, a methodology has been developed for determining the inherent design items that affect safety hazards. Though serious consideration has already been given to the normal intrinsic safety and explosion-proof characteristics of a system, the problem may be the system itself rather than the more immediately noticeable system components. In monitoring or controlling items located in underground coal mines, the hardware reliability of a system is seldom recognized as a potential safety hazard. The software or program operating such a system is never considered as a potential safety hazard because it is, in many cases, located outside the hazardous area. In reality, electronic technology is outstripping the industry´s normal view of safety and is quickly growing unseen potential safety problems. These unseen problems are a combination of hardware and computer software that must be identiried and analyzed. The methodology developed for analyzing electronic and computer-based hardware/software systems and the results of analyses completed by the West Virginia University (WVU) research team are presented. A WVU-designed distributed microprocessor-based mine environmental monitoring/control system and two other commercially available systems have undergone detailed analyses. As a result of the developing methodology, a set of design guidelines has been developed to ensure that known system design difficulties can be identified from the outset for designers of new mine monitoring/control systems.