Reducing Accident Probability

There are two proposed technologies that use accelerators. One is called accelerator-breeding, as it aims at converting fertile material (e.g., Th-232) into fissile fuel to be used elsewhere in a (conventional) reactor (Lecocq and Furukawa, 1994). This does not in itself reduce accident probabilities, and to achieve this, the reactors should be of the above-mentioned inherently safe type. 

The objective of emergency planning is to reduce die probability of serious loss due to a particular liazardous accident. The probability of an occurrence of a hazardous accident is first evaluated. It is tlien it is assumed tliat, if the accident occurs, tlie worst consequences will follow (tlie so-called worst-case scenario). Procedures for liandling a particular accident are tlien dex eloped and practiced, both to minimize tlie exposure of persoiuiel and to prevent escalation of the original incident. 

Inherent safety is an approach to chemical accident prevention that differs fundamentally from secondary accident prevention and accident mitigation [1-9]. Sometimes also referred to as primary prevention [1-3], inherent safety relies on the development and deployment of technologies that prevent the possibility of a chemical accident1. By comparison, secondary prevention reduces the probability of a chemical accident2, and mitigation and emergency responses seek to reduce... 

Secondary prevention and mitigation, by themselves, are unable to eliminate the risk of serious or catastrophic chemical accidents, although improved process safety management can reduce their probability and severity. Most chemical production involves transformation processes, which are inherently complex and tightly coupled. Normal accidents are an unavoidable risk of systems with these characteristics [11]. However, the risk of serious, or catastrophic, consequences need not be. Specific industries use many different processes. In many cases, alternative chemical processes exist which completely or almost completely eliminate the use of highly toxic, volatile, or flammable chemicals [12]. 

Human activities are associated with the use and disposal of a variety of chemicals and chemical products. This is the situation for a householder, a laboratory student, and also the industry worker. Many materials have properties that make them hazardous. They can create physical (fire, explosion) or health hazards (toxicity, chemical bums). However, there are many ways to work with chemicals which can both reduce the probability of an accident and reduce the consequences should an accident occur. Risk minimization depends on safe practices, appropriate engineering controls for chemical containment, the proper use of personnel protective equipment, use of the least amount of material necessary, and substitution of a less-hazardous chemical for a more hazardous one. Before beginning any chemical processing or operation, ask What would happen if. .. The answer to this question requires understanding of the hazards associated with chemicals, the equipment, and the procedure involved. The hazardous properties of the material and its intended use will dictate the precautions to be taken. 

The probabilistic safety assessment (PSA) for the steam reforming process was carried out to investigate the cause of an accident on combustible gas leak and a conceptual design on a countermeasure against explosion was carried out aiming at reducing the probability ofthe combustible gas leak less than 10-6/year. The rupture of combustible gas pipes is considered as the cause of the leakage. 

Present nuclear power plants must be designed and operated to current safety objectives and principles in order to achieve a high level of safety. Nuclear power has a small environmental impact when operating as designed, but faces serious public concerns about the risk of oif-design accidental releases. This has stimulated the current engineering concentration on reducing the probability of such accidents. 

If in the future this factor increases ten times, it will take us to reduce this probability ten times for 1 reactor-year in order to keep today s expected value of frequency of severe accident realization [15]. 

Accidents due solely to the material itself are therefore fairly rare the risk comes from the medium in which the material is found, namely, traffic. Those responsible for transport safety have to deal specifically with traffic accidents and the consequences arising from the presence of dangerous materials, and must attempt to reduce the probability of... 

In order to reduce the probability of a traffic accident, the safety of vehicles is continually being improved, for example, by improving braking or by lowering the center of gravity of tanks. Attempts are also being made to improve driver behavior by awareness and reflex training. 

To reduce the probability of traffic accidents and to prevent contact between unconfined material and a target is more problematic and sometimes contradictory. For example, in the case of land transport, there may be a choice between rail and road. It might seem preferable to choose rail since the overall probability of an accident is very low, but railway lines in general pass through built-up and heavily populated areas, whereas bypasses on trunk roads often avoid these. 

Under the Occupational Safety and Health Administration (OSHA) Act, an employer who does not control noise so as to minimize fatigue and reduce the probability of accidents can be charged with a violation of the standard. Both employers and employees are obligated to observe existing noise standards. An employee who does not comply with previously described procedures for his or her welfare and suffers a loss of hearing can be charged with misconduct. 

The model provides a set of indicators in order to represent dynamically the activities that have the potential to reduce the probability of accident inside the area. It enables competent authorities to optimize inspection scheduling and planning activities in an homogeneous industrial cluster. The heuristic procedure is based on priority index (PI) evaluated for each establishment (or imit), taking into accoimt evaluation of inherent hazards, of safety conditions and previous accidents. 

Investigation into each and any of air events should be started with reconstruction of particular links of the chain of errors , which at the same time is the chain of causes . The chain of errors is a term that describes errors in human-performed actions as effects of a series of coincidences that result in an incident/accident. Since any chain shows no more strength than its weakest link, removal of that weakest link could potentially prevent the accident, or reduce the probability that the accident occurs, or possibly reduce the effects. 

The purpose of these two additional requirements is to demonstrate either an increased capability of a Type A packaging for liquids to withstand impacts and hence to indicate that the fraction of the contents that would be released in an accident would be comparable with that released from a Type A package designed to carry dispersible solids, or to provide a supplementary safety barrier, thereby reducing the probability of the liquid escaping from the package even if it escapes from the primary inner containment components. 

Recommended Controls column Recommendations for eliminating the hazard or controlling it by reducing the probability and/or severity of an accident resulting from the hazard. 

These analytical methodologies where first developed for the petrochemical industry with the intent to reduce the probability and/or consequences of a major incident that would have serious or even devastating impacts on the employees, the public, property (both company-owned as well as offsite), and/or the environment. Extension of these concepts into a more broad application in industry in general could have far-reaching benefits and present certain advantages to an organization s overall accident/incident prevention programs. 

Concept to Action Using High-Reliability Tools to Reduce the Probability of Medical Accidents... 

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