Risk score formula

After running many plausibility and efficacy tests, the following risk scoring formula was developed ... 

The values derived are placed in the Risk Score Formula. Then yon would calculate a risk score. 

Risk Score Formula = Consequences x Exposure x Probabihty... 

A risk score will not necessarily gamer snpport for the removal or reduction of a potential hazard. The questions asked are, How mnch will it cost and How much hazard reduction will be derived from fixing the dangerous situation Fine (1973) went beyond the risk score and developed a Jnstification Formula. The formula includes factors for cost and the degree of correction. The resulting rating values for the cost and degree of correction factor can be extracted from Table 1.1. The Justification Formula is as follows ... 

A formula has been devised which weighs the controlling factors and calculates the risk of a hazardous situation, giving a numerical evaluation to the urgency for remedial attention to the hazard. Calculated Risk Scores are then used to establish priorities for corrective action. 

An additional formula weighs the estimated cost and effectiveness of any contemplated corrective action against the Risk Score and gives a determination as to whether the cost is justified. 

Fine s paper is thought-provoking, a valuable resource, and somewhat hard to find. For those who would like to explore a three-dimensional risk-scoring system to which an additional formula is applied to determine whether the risk reduction cost can be justified, an abbreviated version of Fine s paper may be found in the Addendum at the end of this chapter. The substance of the paper remains intact. 

Having decided to include frequency of exposure as a separate element to be scored, the question became how to assure that scoring computations, particularly for severity, are not adversely skewed. Thus, for this Risk Score Formula, the rating for frequency of exposure is not an equal multiplier. Rather, it is added to the rating for occurrence probability to produce a mid-level score that is then multiplied by the severity rating ... 

Substitute into formula and determine the Risk Score ... 

Using the Risk Score Formula. (Note In this case there are two hazards, so the evaluation is done in two parts, one for each of the hazards, and the total scores... 

It should be noted that the elements of the numerator of this formula are the same as the Risk Score formula described in Chapter 2. We have simply added a denominator made up of two additional elements which are as follows ... 

Fine s first component is a risk score, which compiles numerical values related to consequences, exposure, and probabilities. To calcirlate a risk score, extract the rating values from the Justification Formula Rating Summary Sheet found in Figure 1-4. The valires derived are placed in the Risk Score Formirla. Then you would calculate a risk score. 

An REI value for each impact should be determined and multiplied by the IP value for that impact. The product of each of the four is added together to determine IMPACT (IMP). The IMP is then added to the product of P and OS. Thus, the Risk Assessment Value (RAV) allows for ranking the hazard. The higher the score, the higher the risk. The highest risk assessment value would be 70 (Highest Risk) to a low of 11 (No Risk). Ranking risk is not an exact science but it is an approximation of the potential risk. A summary formula for the RAV is... 

Once the risk rating is established in relation to a particular task or activity, the risk rating can be compared with the scale to see whether a method statement should be called for. Of course, an organisation may wish to set a higher standard than this by revising the formula, or the scale itself. Several companies have decided that they will always ask for a method statement from every contractor this system is designed simply to offer a decision method which may prove of interest to the reader. Intermediate values can be used — the scoring is not restricted to the numbers shown. 

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