Measurements accident frequency rates

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. 

Control measures in use 4. Periodic monitoring 4. Accident frequency rate. 

Measurements of results (injuries/illnesses/and other types of accidents frequency rates)... 

First and foremost, management must clearly understand and appreciate what accident frequency rates are and how they should be used. This is done only by educating members of management on safety measurement techniques so they can understand the strengths and weaknesses of results, measurements, causes, and effects. Once they understand the potential and how to interpret and use aU three types of measurements, they wiU be more likely to employ a balanced and professional approach to using accident statistics. 

Unfortunately the measure of safety performance has traditionally been accomplished only by means of accident rates, such as Injury Frequency Rate (IFR) or Severity Rate (SR), that are typically categorized only... 

Measurable — Your safety goals must have a way to show progress. Fortunately, this usually isn t a problem in a typical motor carrier environment where most activities are quantifiable (e.g. vehicle accident frequency, driver turnover rate, record of duty status violation rate, etc.). Being measurable means your goals should have ... 

One or more indices describing incident performance according to various units of measurement (e.g., disabling injury frequency rate, number of lost-time accidents, disabling injury severity rate, number of first-aid cases, or dollar loss). It may also refer to a summary statement describing incident performance. 

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. 

Any simple measurement of performance in terms of accident (injury) frequency rates or accident/incident rate is not seen as a reliable guide to the safety performance of an undertaking. The report finds there is no clear correlation between such measurements and the work conditions, in injury potential, or the severity of injuries that have occurred. A need exists for more accurate measurements so that a better assessment can be made of efforts to control foreseeable losses. 

There are various ways to measure the resuits of work being done to prevent accidents. The effects of having an accident include, for example, injuries, iiinesses, anguish suffering, financial losses, increased insurance costs, poor productivity, absenteeism, production deiays, high labor costs, machinery downtime, and poor community image. Two types of measurements of results are commonly used. The first, and by far the most common, tracks accident frequency and severity rates. The... 

There are many good reasons for using accident frequency and severity rates. As mentioned earher, these measurements of results are part of any effective safety management program. When accident frequency and severity rates are properly used, they can lead to an increased commitment to preventing accidents. Several of the most obvious benefits of frequency and severity rates are ... 

Once a system of measurement has been established, it is much easier to communicate the effectiveness of a program to employees and, just as important, to upper management. Providing meaningful data on injury rates, accident frequencies, and property damage is critical when funding decisions must be made. 

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 first step in designing a road safety development index (RSDI) is to come up with a comprehensive set of indicators, which includes as far as possible aU the main parameters in road safely of human-vehicle-road-enviromnent-regulation, instead of considering a few factors such as accident rates per population or per kilometoe driven. In addition, this index should be as relevant as possible for different countries, especially in developing countries. The choice of accident risk and exposure variables is necessary to what is available in international data and what is considered necessary for meaningfiil comparisons. Commonly, frequencies of aimual numbers of vehicles, accidents, injured and killed people are some kind quantification and relatively easy to define and to measure in different countries. But differences in definitions, noncollection of data, non-rehabUity of data and under-reporting are problems for effective measurements of road safety. 

Nearly all attempts to examine human factors found larger behaviour influences. Most of the accidents resulted from the violation of traffic laws. In one study carried out in Indiana State in USA presented in (Oppe, 1993), the frequencies of cause factors were calculated. The results have shown that in 70.7% of accidents the causes were human, 12,4% environmental and 4.5% vehicles. Furthermore, the measure of Traffic Risk is widely accepted in international comparisons and it deals with the fatalities rates per vehicles, per vehicles-km or per person-km. 

With an annual budget of about 300 million, OSHA is about five percent the size of the Enviroiunental Protection Agency (Salwen 1993). The federal government has six times more fish and game inspectors than health and safety inspectors (Ball 1992). As demonstrated in the Inq)erial Food Product s fire, OSHA frequently steps in only after a disaster. One might believe the limited federal commitment to worker health and safety would lead to a vast and expanding frequency of workplace accidents and diseases. As shown in Figure 1.1 the frequency of workplace deaths as measured by National Safety Council statistics has declined dramatically over the last 64 years. In 1928, for every 1(X),(XX) workers there were 15.8 workplace fatalities. By 1992 the rate of fatalities had fallen by about 80 percent to 3.3 per... 

In contrast, a well-controlled field trial, in which the expected cost of being at fault in an accident was increased, was indeed published. The intervention resulted in a marked reduction in the accident rate of the military driver population involved (Barmack and Payne, 1961), as it did in the general driver population in Japan (see Chapter 5). Military personnel at a U.S. air force base in Texas were informed that their ranks were in jeopardy, and that they even ran the risk of dishonourable discharge from the service, if they were found to be at fault in a road accident. Referral to a psychiatrist was another unpleasant possible consequence. These measures were put into effect for 1 year and the results were compared with the accident rate before the measures were instituted, as well as with the accident rates of military personnel at other bases without the programme and with general trends. The authors concluded that the number of accidents of personnel at the experimental base diminished by 50%, the total frequency of personal injuries by 54%, and of personal injury to the driver by 60%. 

Various forms of accident data are collected by organisations and a number of standards indices are used, e.g. rates of accident incidence, frequency, severity and duration. Accident data are based on information compiled from accident reports. As such, they are a reactive form of safety monitoring and should not, of course, be used as the sole means of measuring safety performance. However, they do indicate trends in accident experience and provide feedback which can be incorporated in future accident prevention strategies. The following rates are used ... 

A measure of the frequency or probability of accidents in the activity per unit of exposure. Example, continued In the LTI-rate, the number of accidents per million work-hours in the activity in question determines the frequency. 

It is the responsibility of Norskoil s SHE manager to follow up on the accident statistics from the yards. He monitors the SHE performance in this way and compares the results with the project s goals. NORSOK S-CR-002 defines the requirements as to reporting of accident statistics from the EPC contractor to Norskoil. Based on this information, Norskoil follows up on the following SHE performance measures LTI-rate, LTI -rate (i.e. the frequency of lost-time injuries with potential for severe harm, see Table 17.2) and the TRI-rate. 

Fig. 5. Death rates in construction for USA, UK and Ontario deaths per hundred thousand workers. In relating the Ontario death rate to the UK death rate it has been noted that in Ontario a non-construction worker death resulting from a construction site accident is included, whereas in the UK it is excluded from the count. Only when frequencies can be compared is there real measurement value...

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. 

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