Accident data

The frequency analysis step involves estimating the likelihood of occurrence of each of the undesired situations defined in the hazard identification step. Sometimes you can do this through direct comparison with experience or extrapolation from historical accident data. While this method may be of great assistance in determining accident frequencies, most accidents analyzed by QRA are so rare that the frequencies must be synthesized using frequency estimation methods and models. 

ACCIDATA, 1992, Accident Data, PRINCIPIA, Engenharia de Confiabilidade e Informatica Ltda, Brazil. 

Curve Enveloping Accident Data and a Linear Envelope for a Looser Straight-Line... 

The traditional approach, because it sees the major causes of errors and accidents as being attributable to individual factors, does not encourage a consideration of the underlying causes or mechanisms of error. Thus, accident data-collection systems focus on the characteristics of the individual who has the accident rather than other potential contributory system causes such as inadequate procedures, inadequate task design, and communication failures. 

Other important considerations in the design of an IRS are the data storage and analysis requirements. These need to be considered early in the design of the system if it is to be used to research and display trends effectively. For example, in addition to the answers to specific questions, the accident data analyst may wish to make use of free text descriptions of the circumstances of the accident. This implies that a text-based retrieval system will be required. 

The databases that exist in most large companies for the accident data are usually oriented toward coded information. Each of the items on the form is... 

The selection process of retrieving these case histories from the 18,000 is based on the availability of rich accident data located within the chemical process industry. A detailed discussion of the selection process can be found in Chapters 3 and 6. 

As noted in the preceding discussion of Sensitivity Data , TNT is comparatively insensitive and safe to handle. Consideration of the compilation of accident data (Ref 3) in Table 10 leads to the same conclusion. It is also noted that no one area is especially accident prone. The incident involving the expin of 10000 lbs is discussed in the section on Preparation portions of the plant were redesigned as a result. A Safety Data Statement (Ref 2) summarizes factors pertinent to its handling, shipping and use... 

Accident data show a strong influence of time-of-day factors. Thus, hours-of-service regulations cannot be based only on the overall length of the duty period. Instead, they must include a careful consideration of the positioning of the duty period within the 24-hr cycle. In addition, inverted duty-sleep periods need... 

Hence, it is necessary to collect near miss data as well as accident data. The much more numerous unsafe situations (both chronic and sudden) and even more abundant human errors not resulting in serious consequences are assumed to have the same psychological root causes as the tiny subset that actually develops into an accident. The same data-base size may thus be reached much sooner, or a certain observation period may yield a much more reliable insight into the causes of (near-) accidents. 

Hale, A.R., Karczewski, J., Koornneef, F. and Otto, E, (1991). IDA an interactive program for the collection and processing of accident data. In T.W. van der Schaaf, D.A. Lucas and A.R. Hale (eds), Near Miss Reporting as a Safety Tool Butterworth-Heinemann. Oxford. 

It can sometimes be misleading to compare oil spill statistics, however, because different methods are used to collect the data. In general, statistics on oil spills are difficult to obtain and any data set should be viewed with caution. The spill volume or amount is the most difficult to determine or estimate. For example, in the case of a vessel accident, the exact volume in a given compartment may be known before the accident, but the remaining oil may have been transferred to other ships immediately after the accident. Some spill accident data banks do not include the amounts burned, if and when that occurs, whereas others include all the oil lost by whatever means. Sometimes the exact character or physical properties of the oil lost are not known and this leads to different estimations of the amount lost. 

Likelihood Based on historical accident data and understanding of safeguards in place and their reliability Based on threat, capabilities and vulnerability and understanding of safeguards in place and their reliability... 

Comparison of different sources of data (specific accident data for a mode as compared to generic data)... 

The transportation manager will work with carriers and the consultant to collect carrier-specific accident data. 

Generic Data Data that are built using inputs from all operations within a company, from literature sources, from past TRA reports, and from commercial databases such as accident data for all vehicles vs. tracks only vs. certain types of trucks. 

In my view, realistic safety information should form a specific section in a job description. Figure 3.1 is an example of what a safety section in a job description might look like. The acmal information in the safety section of a job description should be derived from a careful analysis of the job, from internal accident data associated with the job, and from global accident trends associated with the job. For the information to help with expectation setting, it needs to be as realistic (accurate) as possible. Furthermore, the organization should not distort or adjust the ratings based on their expectations of how safety management systems are likely to reduce the risks. 

Hanecke, K., Tiedemann, S., Nachreiner, F., Grzech-Sukalo, H. (1998). Accident risk as a function of hour at work and time of day as determined from accident data and exposure models for the German working population. Scandinavian Journal of Work, Environment and Health, 24, 43-4S. 

Chua, D.K.H. and Goh, Y.M. (2004) Utilising the modified loss causation model for the codification and analysis of accident data. In S. Rowlinson (ed.). Construction Safety Management Systems, pp. 443-63. Spon Press, London. 

Figure 1. Construction safety checklist scores and accidents data analysis.

Table 2. The risk, economy and accident data in Chongqing City, China.

These categories of errors are extensively used in accident data collection. However, the fact remains that concepts of unsafe conditions and unsafe acts are usually simplistic and definitions are variable from place to place. 

Accident data for accidents the driver was involved in for the 3 year period preceding the date of the employment application (includes accidents as defined in 390.5 and any other accident information the previous employer... 

Table 5-1. Severe accident data (indicative figures)...

It is possible to make an assumption, also on the basis of accident data, that the coarser part of the powder produced (from 10 pm to 1 mm), with an overall weight approximately equal to the total one (99 per cent), is deposited over a radius of a few kilometres (2 km are assumed) from the release... 

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