Inherent Safety Reviews

Inherent Safety Review Methods and Avaitahte Training 

In a review of inherent safety awareness and practices in the United Kingdom, Mansfield (1994) reported a general lack of awareness 

A number of companies have recently described their inherent safety review practices  

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Exxon Chemical (French et al., 1996 Wixom, 1995) has developed an inherent safety review process, and its application at various points in the process life cycle. 

Union Carbide (Lutz, 1995a,b) published a checklist used in their inherent safety reviews. 

The objectives for an inherent safety review are to employ a synergistic team to ... 

The first major objective for the inherent safety review is the development of a good understanding of the hazards involved in the process. Early understanding of these hazards provides time for the development team to implement recommendations of the inherent safety effort. Hazards associated with flammability, pressure, and temperature are relatively easy to identify. Reactive chemistry hazards are not. They are frequently difficult to identify and understand in the lab and pilot plant. Special calorimetry equipment and expertise are often necessary to fully characterize the hazards of runaway reactions and decompositions. Similarly, industrial hygiene and toxicology expertise is desirable to help define and understand health hazards associated with the chemicals employed. 

Reducing and eliminating hazards and their associated risks is the second major objective. Applying inherent safety principles early in the product/process development effort provides the greatest opportunity to achieve the objectives of the inherent safety review process for the project at hand. If these principles are applied late in the effort the results may have to be applied to the project after next as the schedule may not permit implementation of the results. 

Experience with inherent safety reviews indicates that project investment costs are frequently reduced as a result of this exercise. Eliminating equipment and reducing the need for safety critical instrumentation are typically the main contributors to investment reduction. Capturing these potential savings depends greatly on the timing of the reviews. 

Inherent safety reviews should be considered during appropriate stages of a typical project s life cycle. Suggested timing includes ... 

Good preparation is very important for an effective inherent safety review. Preparation for the review is summarized in Figure 7.1 and includes the following items ... 

After the background information is developed, the inherent safety review can be arranged. The review steps are summarized in Figure 7.2. Steps proposed for the review are as follows ... 

During the inherent safety review, at the design development stage, identify potential human factors/ergonomics issues that should be addressed by the design team. 

It is not unusual to have several inherent safety reviews during the product/process development effort. Early reviews will often not have all of the information required for Steps 1 to 9. The follow-up items will describe what is necessary to obtain the missing information such as toxicity data on new intermediates or products of undesired reactions. 

In the chemistry forming inherent safety review, the team will cover such things as ... 

Inherent Safety Review Initiates Project Human Factors/Ergonomics Effort... 

As noted in Step 13 of the inherent safety review at the design development stage, the team reviews the process to develop a list of potential ergonomics/human factors issues. This list provides input to the design team so that these issues can be addressed as the design progresses. 

Good Preparation Required for Effective Inherent Safety Reviews... 

The completeness of the information described in Steps 1 to 9 prior to the review will determine the quality of the inherent safety review. The chemist needs to define the desired reactions, and to develop an understanding of potential side reactions. Effects on reaction chemistry need to be developed for mischarges or process deviations. These information requirements on process chemistry are discussed in Section 4.2. 

Experience has shown that reactive chemistry hazards are sometimes undetected during bench scale and pilot plant development of new products and processes. Reactive chemistry hazards must be identified so they can be addressed in the inherent safety review process. Chemists should be encouraged and trained to explore reactive chemistry of "off-normal operations. Simple reactive chemicals screening tools, such as the interactions matrix described in Section 4.2, can be used by R D chemists. 

If an organization chooses to include inherent safety reviews in its implementation approach, training should be included on how to conduct an inherent safety review. 

Companies may wish to develop workshops to train potential team members in the inherent safety review process. The workshop can provide background information on inherent safety concepts, the extensive systems required to manage hazardous materials, and information on the inherent safety review process. Videos, problems, examples, and team exercises can be included to enliven the education process. 

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. 

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