Fatal Accident Frequency Rate

One approach is to compare the risks, calculated from a hazard analysis, with risks that are generally considered acceptable such as, the average risks in the particular industry, and the kind of risks that people accept voluntarily. One measure of the risk to life is the Fatal Accident Frequency Rate (FAFR), defined as the number of deaths per 108 working hours. This is equivalent to the number of deaths in a group of 1000 men over their working lives. The FAFR can be calculated from statistical data for various industries and activities some of the published values are shown in Tables 9.8 and 9.9. Table 9.8 shows the relative position of the chemical industry compared with other industries Table 9.9 gives values for some of the risks that people accept voluntarily. 

Table 1-8 Risk of Death from Various Activities in the United Kingdom, Showing Fatal Accident Frequency Rates ...

Societal risks are usually given as fatal accident frequency rates (FAFRs). The fatal accident frequency rate is defined as the number of fatal injury accidents in a group of 1000 in a working lifetime (10 hours). 

The output from Stage (c) may be expressed in the form of individual risk or of societal risk. Individual risk is tiie probability of death to an individual within a year (e.g. 1 in 10 per year). Societal risk is the probability of death to a group of people - either employees or members of the general public - within a year (e.g. a risk of 500 or more deaths of 10 per year). Societal risks are usually given as fatal accident frequency rates (FAFRs). The fatal accident frequency rate is defined as the number of fatal injury accidents in a group of 1000 in a working lifetime (10 hours). 

Fatal accident frequency rate Film forming fluoroprotein foam Flameproof... 

Fatal Accident Frequency Rates" (FAFR) for different jobs and activities in Great Britain (after Gibson 1976)... 

The Fatal Accident Frequency Rate (FAFR) expresses the number of fatalities occurring per 1 million work hours ... 

The magnitude of the risk to people is normally taken as the Fatal Accident Rate (FAR). This is calculated by multiplying the size of the hazard (measured in fatalities per hazardous event) by the frequency of the hazardous event (measured in events per year). The FAR has units of fatalities per year. 

The hazard analysis of any industrial process impacts on risk assessment. Risk assessment involves the estimation of the frequency and consequences of a range of hazard scenarios and of individual and societal risk. The risk assessment process is shown in Figure 3.1. The risk criterion used in hazard analysis is the fatal accident rate (FAR). The FAR is defined as the number of fatalities per 108h exposure. The actual FAR in the U.K. was 3.5 in the chemical industry in 1975. No doubt the ideal FAR value should be zero, which is difficult to achieve in practice. 

The standard way of reporting the results from QRAs/PRAs is to present calculated frequencies (expected values) and probabilities, for example expressed by PEL (Potential Loss of Life) values, FAR (Fatal Accident Rates) values, IR (Individual Risk) values and F-N-curves (Frequency-Nmnber of fatalities). These risk indices form a risk picture, which constitutes the basis for the risk evaluation, to determine the... 

The second view is macroscopic. In case more than one event is evaluated, an aggregation of the single events is possible in order to assess the overall effects. If the sample under investigation happens to contain accident and non-accident events, an accident rate or prevention rate can be calculated as ratio of frequency of accidents (or one minus accidents) with a measure by frequency of accidents without the measure. Summary statistics can also be computed in non-accident events by statistically evaluating the indicators defined on the physical level. In comparison to a baseline without measure the change due to a specific safety measure can be evaluated at the desired level of detail. Within the accident group, rates for specific injury severities as well as a fatality rate can be estimated. 

A further study analysed both fatality and disabling injury rates across all mines in the period 1973-75 and found that when other relevant factors were controlled both of these indicators were inversely related to the frequency of inspection. The study s author concluded that increasing inspections by 25 per cent would have produced a 13 per cent decline in fatal accidents and an 18 per cent decline in disabling accidents (Boden 1985, p. 497). 

The S-rate (severity rate) is less sensitive to reporting inaccuracies than the LTI-rate. One single accident resulting in a long period of sick leave may, however, dominate the statistics. It follows that the S-rate may vary considerable from period to period, especially in small companies. Another problem with the S-rate has to do with the fact that the sick leave for an injury may extend into the following periods. The true S-rate is thus not available until all injuries from a period have been closed. Due to the low frequency of fatalities, FAR (fatal accident rate) is rarely useful as a SHE performance indicator other than for very large companies in hazardous branches of industry. 

QRA is a process of investigating potential accidents and expressing the results in terms of measures that reflect both the frequency and the potential loss severity of each type of accident that can occur (Henley and Kumamoto (1992)). The measures in most common use are Fatal Accident Rate (FAR), Individual Risk Per Annum (IRPA) and the FN curve. 

Quantitative risk assessment (QRA) The systematic development of numerical estimates of the expected frequency and consequence of potential accidents associated with a facility or an operation. Using consequence and probability analyses and other factors such as population density and expected weather conditions, QRA estimates the fatality rate for a given set of events. 

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