Risk assessment factors

Table 2. Weight coefficient of single debris flow risk assessment factors.

If a risk/cost formula is applied, it would determine that the risk assessment factor is not very high, principally because the lift is only performed twice a week and not regularly. Also, using a jnstification factor, it shonld definitely be fixed or removed. The analysis sends a mixed message to management. So the case to have the problem fixed may not be very strong in this sitnation. A cost avoidance approach may be a better avenue. First, let us assume that a worker gets injured. What are the costs incurred ... 

Risk assessment factor = Consequence x exposure x probability... 

Multiply the values that you have selected for consequence, exposure, and probability together to determine this risk assessment factor and find the value on the following scale. 

The use of flame retardants came about because of concern over the flammabiUty of synthetic polymers (plastics). A simple method of assessing the potential contribution of polymers to a fire is to examine the heats of combustion, which for common polymers vary by only about a factor of two (1). Heats of combustion correlate with the chemical nature of a polymer whether the polymer is synthetic or natural. Concern over flammabiUty should arise via a proper risk assessment which takes into account not only the flammabiUty of the material, but also the environment in which it is used. 

There are a large number of standard methods suitable for each stage in the hazard analysis and risk assessment procedure. The selection of the proper method depends on several factors. Some of these are the type of process, the stage in the lifetime of the process, the experience and capabiUties of the participants, and the step in the procedure that is being examined. Information regarding the selection of the proper procedure is available in an excellent and comprehensive reference (1). 

A company produced bromine in Arkansas and brominated compounds in New Jersey. A risk assessment resulted in a recommendation to consider the transfer of the bromination processes to the bromine production site in Arkansas. Economics and the decrease in risk justified such a transfer and it was done. Although safety was not the only consideration, it was an important factor in this decision. 

Lisl of any weighting factors modifying the HEPs used in the risk assessment. 

THERP (NUREG/CR-1278), is used to estimate HEPs for a risk assessment. It provides error probabilities for generic tasks and describes the process used to modify these rates depending on the specific performance shaping factors (PSFs) involved in the task... 

Performance-influencing factors analysis is an important part of the human reliability aspects of risk assessment. It can be applied in two areas. The first of these is the qualitative prediction of possible errors that could have a major impact on plant or personnel safety. The second is the evaluation of the operational conditions under which tasks are performed. These conditions will have a major impact in determining the probability that a particular error will be committed, and hence need to be systematically assessed as part of the quantification process. This application of PIFs will be described in Chapters 4 and 5. 

Banks, W., Wells, J. E. (1992). A Probabilistic Risk Assessment Using Human Reliability Analysis Methods. In Proceedings of the International Conference on Hazard Identification and Risk Analysis, Human Factors, and Human Reliability in Process Safety. New York American Institute of Chemical Engineers, CCPS. 

The risk inventory or risk evaluation is die ne. t part of die hazard survey. It is not practical to expect the plan to cover every potential accident. When die hazards liave been evaluated, die plan should be focused on die most significant ones. This risk assessment stage requires die technical expertise of many people to compare die pieces of data and detennine die relevance of each. Among die important factors to be considered in performing die risk evaluation are die following ... 

The following factors should be reviewed in the liazard identification step of a risk assessment effort ... 

Generally, the slope factor is a plausible upper bound estimate of the probability of a response per unit intake of a ehemieal over a lifetime. The slope factor is used in risk assessments to estimate an upper-bound lifetime probability of an individual developing cancer as a result of e.xposure to a particular level of a potential carcinogen. Slope factors should always be accompanied by the weight-of-evidence classification to indicate the strength of the evidence that the agent is a human carcinogen. Calculational details are presented below. 

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