INDEX Accidents

Risk indices are usually single-number estimates, which may be used to compare one risk with another or used in an absolute sense compared to a specific target. For risks to employees the fatal accident rate (FAR) is a commonly apphed measure. The FAR is a singlenumber index, which is the expected number of fatalities from a specific event based on 10 exposure hours. For workers in a chemical plant, the FAR could be calculated as follows ... 

Equivalent Social Cost index Fatal accident rate (discussed in Section 18.5) ... 

All surveyors need a database of technical information, which should include reports of accidents or of defects that could lead to accidents derived from other sources. He also needs a regular supply of technical documentation from his head office that keeps him abreast of technical developments. If his company operates an effective quality assurance system, they will periodically check that he is keeping these data properly and they may control the indexing of them. 

Dow-Chemical Exposure Index (CEI)3, which are two popular forms of hazards survey. These are formal systematized approaches using a rating form, similar to an income tax form. The final rating number provides a relative ranking of the hazard. The F EI also contains a mechanism for estimating the dollar loss in the event of an accident. 

The comparison of the safety of equipment is not straightforward. It depends on several features of both process and equipment themselves. It can be evaluated from quantitative accident and failure data and from engineering practice and recommendations. Experience has been used for layout recommendations and for the development of safety analysis methods such as the Dow E F Index (Dow, 1987). Statistics contain details, causes and rates of failures of equipment and data on equipment involved in large losses. 

It was noticed that the scale of penalties is much narrower than the scale of recommended layout spacings or the cost of large losses. This is because the Dow F E Index takes into account only large rotating equipment, which is known more likely to contribute to accidents than smaller equipment. Thus the smaller equipment is safer and it is not given penalties. 

The chemical and most process factors affecting the index are quite straightforward to estimate. More problematic are the equipment safety and the safety of process structure. The equipment safety subindex was developed based on evaluation of accident statistics and layout information. The evaluation of the safe process structure subindex is based on case-based reasoning, which requires experience based information on accident cases and on the operation characteristics of different process configurations. 

Chung, P. W. H. Jefferson, M. 1997. Accident Databases - Indexing and Retrieval. EC/EPSC seminar on "Lessons Leamt from Accidents", Linz, 16-17 October. 

OSHA IMIS Records of workplace inspections, including those prompted by accidents where a worker is injured 1984-Present Information from OSHA field inspections, a third party More accurate description of impacts on employees and contractors Keyword indexing allows for easy search and retrieval Not comprehensive, limited to incidents selected by OSHA Inspections without abstracts cannot be keyword searched causal information unavailable Designed to assist compliance enforcement, not to report on incident causes Limited information from State-Plan states Not designed to be a lessons-leamed database... 

This handbook, too, may contain errors while certainly holding reports, accident explanations and claims of hazard which the editor does not believe (usually indicated in phraseology or cross-reference). Nor is it automatically to be assumed that all listed and cross-indexed components of complex mixtures contributed to the accidents reported. Accept nothing uncritically ... 

The datasheets which now accompany pure or bulk chemicals, even from laboarory supply houses, are becoming rapidly more credible, thus trustworthy [1]. However two surveys of Material Safety Datasheets (MSDSs), apparently largely for compounded formulations, showed that only a tenth were judged both adequate and correct, while two thirds were both inadequate and in error [2]. Errare est humanum - this handbook, too, may contain errors while certainly holding reports, accident explanations and claims of hazard which the editor does not believe (usually indicated in phraseology or cross-reference). Nor is it automatically to be assumed that all listed and cross-indexed components of complex mixtures contributed to the accidents reported. Accept nothing uncritically ... 

Another instructive comparison can be made by comparing fatalities in different activities. Here we use the Fatal Accident Rate index (FAR) that gives the number of fatalities for 108 hours of exposure to the hazard [3, 4]. Some activities are compared in Table 1.2. This shows that even with better statistics in terms of fatali-... 

Hepatic Effects. Exposure to 2,3,7,8-TCDD induces liver microsomal enzymes in both humans and animals, regardless of the route or duration of exposure. Increased urinary -glucaric acid (UGA) excretion, an indirect index of enzyme induction, was found in children with chloracne living in the Seveso area following the 1976 industrial accident (Ideo et al. 1982). Biochemical changes (increased... 

Table 1-5 1995 Relative Risks of Fatal Accidents in the Workplace Using Mr. Toscano s Relative Risk Index...

Until now research efforts in safety management have been focussing primarily on the number of accidents (system failures leading to personal injuries andlor material damages) as the prime index for system safety. There are three main reasons for redirecting our attention in this respect ... 

Dow Fire and Explosion Index. The Dow Fire and Explosion Index (F EI), developed by The Dow Chemical Company, is an objective evaluation of the potential of a facility for a fire, an explosion, or a reactive chemical accident. Its purpose is to quantify damage from incidents, identify equipment that could contribute to an incident, and suggest ways to... 

In a Canadian study of 200 000 automobile drivers, aged 67-84, who were followed from 1990 until they reached age 85, or until they emigrated from Quebec, or until 31 May 1993, those who had been involved in an automobile accident in which one person sustained a physical injury were assessed the controls were a 6% random sample of the others (172). Of 5579 patients 20 had been taking lithium within the year before the index date, 19 of whom had been taking it within 16 days before the accident. This compared with 27 of 13 300 patients in the control group (OR = 1.8) for current lithium use, the odds ratio was 2.08. The data on carbamazepine did not show a raised odds ratio. The authors concluded that elderly patients taking lithium have a two-fold increase... 

Chemical Process Safety Report—News and Analysis on Regulation of Chemical Process Safety and Accident Prevention, Thompson Publishing, Washington D.G., (202) 872-4000 or (800) 677-3789. The Chemical Process Safety Report is a comprehensive compliance manual covering OSHA s PSM standard. The publisher updates this howto manual on a monthly basis. The annual subscription includes a valuable indexed ref-... 

Radiation Emergency Assistance Center/Training Site (REAC/TS), includes class schedule for Medical Care and Planning in Radiation Accidents. Web site at http //orise.orau.gov/reacts/index.htm... 

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