Safety systems implement process

Many companies also create verification tracking logs. The verification tracking log is a computerized system that tracks each safety control implementation process and verifies that the control is in place. Typical hazard control verifications are inspection, design review, engineering analyses and calculations, and system testing. See Chapter 5 for more details on hazard tracking. 

The purpose of the logic within the safety interlock system is veiy different from the logic within the process controls. Fortunately, the logic within the safety interlock system is normally much simpler than the logic within the process controls. This simplicity means that a hardwired implementation of the safety interlock system is usually an option. Should a programmable implementation be chosen, this simplicity means that latent defects in the software are less likely to be present. Most safety systems only have to do simple things, but they must do them very, very well. 

CCPS G-25. Guidelines for Implementing Process Safety Management Systems. American Institute of Chemical Engineers, Center for Chemical Process Safety, New York. 

The individuals and firm most familiar with the technology should review the intermediate and final procedures to assure both safety and commercial interests are satisfied. In many batch operations the procedure(s) can be a substantial portion of the process technology package. The procedures represent both a major safety system as well as a propriety technology. The pre-startup review should assure both PHA related and other changes proposed to the procedures have been approved and implemented. 

Implementing an inherent safety review process is one mechanism companies can use to institutionalize inherent safety. The review process should integrate well with company systems for process safety management, new product development, and project execution. Safety, health, and environmental considerations in the new product or process development effort can be strengthened via the introduction of the inherent safety review. Companies may also build inherently safer design concepts into their existing process safety management system and process hazard reviews. 

Guidelines for Implementing Process Safety Management Systems, 1993. 

This chapter addresses all these issues. As with several of the earlier chapters, the overall approach to developing a plan should be modeled on that described in Chapter 5 of the CCPS publication Guidelines for Implementing Process Safety Management Systems. The approach recommended there is summarized in the following paragraphs. 

The growing nse of more complex PAT (versus the historically used simple univariate sensors such as pressure, temperature, pH, etc.) within manufacturing industries is driven by the increased capabilities of these systems to provide scientihc and engineering controls. Increasingly complex chemical and physical analyses can be performed in, on, or immediately at, the process stream. Drivers to implement process analytics include the opportunity for live feedback and process control, cycle time reduction, laboratory test replacement as well as safety mitigation. All of these drivers can potentially have a very inunediate impact on the economic bottom line, since product quality and yield may be increased and labor cost reduced. 

Recommendations should be written clearly and should be practical to implement. Recommendations that target improvements to the inherent safety of the process design are preferred to those that merely add extra protection features. All recommendations will potentially change management systems therefore, it is necessary for the team to consider the imphcations of those changes when developing recommendations. 

The management of process safety is many-faceted. The mitigation systems discussed in this book are only part of a total solution. Structured evaluation of chemical process safety is a process of continuous improvement that includes problem identification, development of proposed solutions, evaluation of solutions against established criteria, and, if appropriate, implementation of solutions. This approach is shown in Figure 1.1. 

Operating Procedures. Employers must develop and implement written operating instructions for safely conducting activities involved in each covered process consistent with the process safety information. The written procedures must address steps for each operating phase, operating limits, safety and health considerations, and safety systems and their functions. Included must be normal... 

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