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To focus on safety requires a comprehensive understanding of the manufacturing process. It is necessary to understand the process in terms of process parameters and process elements, which include the necessary hardware and software that materialize the process. These process parameters and elements need to be understood in terms of their relationships and possible interaction, and how deviations from the normal quantities, settings, or behavior can effect the safe operation of the process. To achieve a safe operating plant, it is necessary to design a process where possible deviations from normal conditions can be kept within specific limits that are dedicated by what is perceived as acceptable risk.

Figure - Safety Management Work Cycle

Next the following topics are addressed:
- Design for Safety
- Safety Analysis
- Safety Management

Design for Safety
The “design for safety” concept can be addressed in two ways. On one hand there is the use of standards, codes and guidelines and on the other hand there are detailed safety analyses. Standards, codes and guidelines mainly exist because of lessons learned from the past, usually as a result from accidents. Standards and codes deal with implementing requirements for a general process or specific applications based on existing knowledge, for example, codes and regulations for pressure vessels [2] or burner management control systems [3]. An advantage of the use of codes and standards is the limited amount of effort to achieve acceptable safety targets. The trade off of this approach is that only the minimum safety requirements are addressed which do not necessarily cover the acceptable risk of the specific process.

Safety analyses go beyond standards and codes. In other words, analysis is useful when there is a need or desire to explicitly evaluate the risk associated with the process, even after compliance with existing standards and codes.

It is acknowledged that implementation of standards and safety analysis are two approaches that complement each other and that actually both should be used [4]. Compliance with the standards and codes achieves a level of required safety, while analyses brings safety within the limits of acceptable risk.

Safety Analysis
Safety analysis starts usually with a hazard and risk analysis. The objective of a hazard and risk analysis is to identify all hazards and their associated risk. It identifies what can go wrong and how it can be prevented or controlled. As result of this analysis it is possible to reduce the associated risk to an acceptable level by either changing the design or adding safety measures to the design. A hazard and risk analysis can show that specific hazards are, or are not, present after code requirements have been compiled with, that further safety measures are, or are not, needed, and what the possible consequence can be if the hazard causes an accident. The outcome from the hazard and risk analysis are recommendations to improve the plant design, incorporate additional safety measures, or define operation and maintenance procedures that minimize or control potential hazards. In other words, the objective of the safety analysis is to manage process parameters or elements in terms of their deviations. The next section will explain how safety is currently managed in the manufacturing industry.

Safety Management
An industrial system can only be safe if all the individual elements of the system are safe and interact with each other in a safe manner. Safety, like quality or profitability, is a basic property of a system and needs to be addressed in a way that considers the individual elements, and their interaction, within the context of the system. The methods, techniques, and resource allocation must be coordinated, well planned, properly justified, and able to address the entire lifecycle of the system; in synergistic and not antagonistic manner with the other basic properties of the system; in other words safety has to be carefully managed.

The Department Of Energy in the US has defined five core functions for safety management that comprise the underlying process for any work activity that could potentially affect the public, the workers, and the environment. These five core functions are (see also Figure):

1. Define the scope of work – Missions are translated into work, expectations are set, tasks are defined and prioritized, and resources are allocated.

2. Analyze the hazards – Hazards associated with the work are identified, analyzed and categorized.

3. Develop and implement hazard controls – Applicable standards and requirements are identified and agreed-upon, controls to prevent/mitigate hazards are identified, the safety envelope is established, and controls are implemented.

4. Perform work within controls – Readiness is confirmed and work is performed safely.

5. Provide feedback and continuous improvement – Feedback information on the adequacy of controls is gathered, opportunities for improving the definition and planning of work are identified and implemented, line and independent oversight is conducted, and if necessary, regulatory enforcement actions occur.

Conclusions
The underlying attribute of the safety management functions is the thorough and an integrated understanding of the process. In practice the challenge for sound safety management will therefore deal with having the right people, with the right knowledge using the right tools for the company’s situation in place. If a company is successful in this endeavor it will be able to make risk-informed business decisions that enable it to manage safety in an for the company economically responsible manner.