Risk assessment safety cases

Keywords Formal safety assessment, marine safety, offshore safety, risk assessment, safety case. 

Merz, H. A., "Methods of Quantitative Risk Assessment The Case of the Propellant Supply System," Minutes of the Twenty-First Explosives Safety Seminar, Houston, TX, Aug. 1984, pp. 1485-1506. 

However, the assessment of the results of the changes over the past ten years also has many positive aspects Companies have become more risk aware, safety cases and safety management systems are positive developments and there is more understanding of how and why risk control and management measures work. 

The same approach to the development of a risk assessment based Case for Safety was subseqnently applied to a number of other circumstances in which new equipment, systems or operations were envisaged. These included, for example ... 

Problems affecting safety must be identified at the earliest possible stage to allow progression of the most cost-effective and efficient solution. Failure to consider and anticipate possible problems at an early stage can be an expensive omission. These risks can be as much of a hazard to the programme as other teclmical and commercial risks. It is not the identified hazard that is the problena. If a hazard has been identified it can be measured it can be fixed and controlled. It is the imidentified hazard that is the problem. A hazard not identified is a hazard not managed. If it cannot be identified, it cannot be measured. If it caimot be measured it caimot be controlled. A safety assessment/safety case is therefore not just what has been done - it is also about how it has been done, and why no more is needed to be done. 

The safety targets and risk levels need to be clearly defined. Murphy (1991) also correctly emphasises that this is a very important (and arguably most neglected) topic as it is the safety acceptance criteria the system is expected to achieve, and hence the standard the safety assessment/safety case will be evaluated against. To successfully conduct the assessment the output should be measurable and achievable in the light of any other contractual constraints. 

The aim of this Appendix is to summarise some of the commonly used safety criteria that may be useful in evaluating the safety of a system. This chapter must be read with an understanding of the contents of Chapters 4 and 5. It is for the safety assessor (with regulatory authority concurrence) to select the optimum criteria (or combination of criteria) from applicable regulations to apply to the specific system level (see Fig. 8.1) under consideration. Most importantly, the chosen criteria must be applied consistently throughtout the complete system safety assessment/safety case. If this is not done then efficient risk comparison will be compromised, and the integration of lower-level safety assessments is boimd to be exceedingly complicated. 

The physical condition and characteristics of the material shipped should be considered in transportation risk assessments on a case-by-case basis. There may be options available to reduce transportation risk by reducing the potential for releases or the severity of the effects of releases. A few possible ways of improving safety by modifying conditions are ... 

Controlling health risks from rosin (colophony) based solder fluxes How HSE assesses offshore safety cases WASP - Quality assmance for chemical analysis... 

The comprehensive and detailed assessment of the risks required for a safety-case can only be satisfactorily carried out for major installations with the aid of computer software. Suites of programmes for quantitative risk analysis have been developed over the past decade by consulting firms specializing in safety and environmental protection. Typical of the software available is the SAFETI (Suite for Assessment of Flammability Explosion and Toxic Impact) suite of programs developed by DNV Technica Ltd. These programs were initially developed for the authorities in the Netherlands, as a response to the Seveso Directives of the EU (which requires the development of safety cases and hazard reviews). The programs have subsequently been developed further and extended, and are widely used in the preparation of safety cases see Pitblado el al. (1990). 

In addition to an overview of government regulations, the book introduces the resources of the AICHE Center for Chemical Process Safety library. Guidelines are offered for hazard identification and risk assessment. The book concludes with case histories drawn directly from the authors experience in the field. 

Pitblado, R. M., S. J. Shaw, and G. Stevens, "The SAFETY Risk Assessment Package and Case Study Applications," in Proceedings of the Safety and Loss Prevention, Chemical and Oil Industries, A4, Singapore (1989). 

All Monsanto PMN s submitted to date have voluntarily included information beyond that mandated by the act. This has, in some cases, included Material Safety Data Sheets, Label information, details regarding the industrial hygiene programs in the proposed manufacturing site(s), risk assessment information and other related information. While this information is not mandated, we believe in most situations it is to our benefit to assist the agency in this way. 

The systematic evaluation of substance properties and predictable or actual exposure patterns over the entire life-time of a substance within the scope of risk assessment is as yet a relatively recent instrument, for which harmonised scientific rales were created in the EU for the first time in 1997 in the form of the Technical Guidance Documents (TGD). An essential element in this range of instruments is how to deal with shortcomings in knowledge. Wherever information is missing, standardised worst-case scenarios are conceived taking into account appropriate safety factors . If under these worst-case assumptions a rele-... 

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