Palle Haastrup

Severity of accidents with hazardous materials: A comparison between transportation and fixed installations

Abstract A review of accident case histories relevant to hazardous materials has been performed. From the literature, 1793 accident case histories involving hazardous materials were identified, most of them from the period 1960–1988. Of these 1793 accidents, 39% happened during transportation. In 682 accidents the consequences included fatalities, and of these 27% involved the transportation of hazardous materials. The accumulated frequency-fatality curves (so-called fN curves) have been constructed and are close to straight lines with a slope of –1, indicating that the probability of having an accident with, for instance, more than one hundred fatalities is approximately ten times lower than the probability of having an accident with more than ten fatalities. The accidents were grouped according to transportation type, and the difference between the various groups was tested using a standard χ 2 approach. No significant difference between fixed installations and transportation was found for accidents having consequences above three fatalities. Differences were found between Western Europe and North America and the rest of the world. Once an accident has happened, it seems to have more severe effects outside Western Europe and North America, both for transportation accidents and fixed installations. Comparison of fN curves for Western Europe and North America from different time periods did not show significant differences, indicating that once an accident has happened, it has the same probability of escalating now, as it had 20 years ago.

An analysis of the database coverage of industrial accidents involving hazardous materials in Europe

Abstract The purpose of the present analysis is to explore systematic ways to address the problem of how many accidents involving hazardous materials actually occur in Europe, and to make a realistic estimate. A framework for predicting the total number of accidents was therefore developed and applied. The analysis is based on 535 unique accident descriptions (of which 107 were fatal accidents) from seven accident databases covering the nine-year period from 1984 to 1992. The majority (70%) of the accident descriptions identified were found in one source only. This indicates that, at best, about 30% of all accidents described may be found in a single database. Two models were developed: the first model was based on ideas similar to ‘chemical reaction kinetics’; the second was more related to ‘estimations of an animal population’. The models predict an average of 87 accidents per year in contrast to the observed average of 59 accidents per year. For fatal accidents, the models predict an average of 14 accidents per year, and the observed average is 12.

Marine Transport of Dangerous Goods. Risk Assessment Based on Historical Accident Data

In this paper marine transport of dangerous goods is surveyed on the basis of 151 accident case histories. Accident frequencies have been estimated for the different accident types (collisions, groundings, fire/explosions and structural damage) and are in the range of 1 × 10−3 to 2 × 10−2 per ship per year. Further estimates of the probabilities of spillage of at least 100 tons of cargo and/or fatalities in connection with the accidents have been made. The consequences measured in number of fatalities were compared for each cargo type (oils and chemicals) and it was shown that accidents involving oils were twice as frequent as accidents involving chemicals. However, the distribution of number of fatalities seems to be similar for the two types of goods. Concerning the local surroundings (port, coastal waters and open sea) it was shown that most accidents, both with small and large consequences, happen in coastal waters. The sizes of the spills have been modelled by linear regression based on accident type and the size of the ship. Fairly good correlation between the spill size and the size of the tanker was shown for groundings, structural damage and fire or explosions.

Reliability of accident case histories concerning hazardous chemicals: An analysis of uncertainty and quality aspects

Abstract A recent analysis of accident case histories achieved from readily available accident lists, has exposed the fact that an accident may be described more than once in the literature. Important discrepancies were found between the various main (accepted) sources in the field of risk analysis and loss prevention. An analysis of the differences found, and an assessment of the quality of accident case histories is attempted. Initially the analysis is limited to the number of fatalities, because this information is easy to measure, often available and lends itself to easy statistical treatment. The number of fatalities can thus be used as an indicator for the variability of the information found in accident case history reporting. The analysis is based on 595 transportation accidents involving hazardous chemicals from road, rail and pipeline transportation modes. Thirty-nine of these accidents were found to have three characteristics in common: (1) they happened before 1980, (2) they resulted in fatalities, and (3) they were described by more than one source. These 39 accidents are used in the analysis of the reliability of the number of fatalities reported in case histories. Sixteen accidents (or 41%) show discrepancies (in terms of fatalities) between the sources. Extrapolating the results of the “fatality” analysis to the other parameters, and supported by an analysis of selected cases, the general quality of information from accident case histories is evaluated. The result is a useful tool for assessing the quality of the various types of information. Using the terms “low”, “medium” and “high” to describe the quality, a table can be compiled. This tool shows that the information on date and place of the accident is of high quality, the event description and the number of casualties are of medium quality, and the information about chemical name and amount is of low quality.

Regulatory requirements for biocides on the market in the European Union according to Directive 98/8/EC.

In early 1998, the European Commission and Parliament adopted a new Directive concerning the placing on the market of biocidal products. The Directive is to be implemented in the member states by May 2000. The member states are currently concerned with the national implementation into legislation whereas the Commission is setting up the proposal for a review programme for the existing active substances and the products in which they are used. This paper describes the effort currently undertaken (up to the end of December 1998) to define the procedures to be used and characterise the substances covered.

Accidents during marine transport of dangerous goods. Distribution of fatalities

Abstract On the basis of 2781 accident case histories, the consequences measured by the number of fatalities from marine accidents (n = 1780) during transport of dangerous goods have been investigated and compared with those from other transport modes (n = 1001). Accidents from marine transport of dangerous goods have been found to have a larger proportion of accidents with fatalities in the range of 10–50 than other transport modes. Therefore, f N curves for marine accidents are not similar to straight lines as usually seen but have a hump. This is probably due to the size of the potentially affected population, which is often in the range of 10–50 during marine transport, reflecting the number of crew members on one or two vessels; further, the population potentially affected is placed in a limited area. Almost all accidents with more than 40 fatalities were collisions, and accidents with more than 100 fatalities were due to collisions between tankers and ferries, which significantly increases the population at risk. In these accidents, the dangerous goods were oil. The high number of fatalities is not surprising, as oil at sea has the potential for surrounding a vessel and catching fire. Differences have been found for the distribution of fatalities between different local surroundings and transport phases. Similarity has been found for the distribution of fatalities for type of cargo, tank type, geographical location and year of accident.

Marine Accident Frequencies – Review and Recent Empirical Results

Marine accident frequencies reported in 20 different sources have been studied and compared. Further than this, comparisons were made with an analysis done by the present authors. There seems to be consistency within the sources in the use of the terms total loss, casualty and accident/incident. The rates were observed to decrease by an order of magnitude going from accident/incident to casualty and likewise from casualty to total loss. The overall frequencies were found to be in the range of 0·0009 to 0·07 total losses per 10 6 ship miles, 0·03 to 1 casualties per 10 6 ship miles, and 0·5 to 13 accidents/incidents per 10 6 ship miles. It was found that the frequency depends on visibility, brightness, geographical environment, age of vessel and size of vessel. Collision and grounding frequencies were found to increase with decreasing visibility, brightness and more restricted waters. Collision frequencies were found to increase with increasing size of vessel. Fire/explosion and structural damage frequencies were found to increase with increasing age, and collisions to decrease with increasing age. No firm trend was found from the effect of flag state or type of vessel.

A Consequence Model for Chlorine and Ammonia Based on a Fatality Index Approach

Abstract In this paper, a simple and transparent consequence model for chlorine and ammonia is proposed based on a fatality index. The parameters for the model can be estimated from historical accident data and avoid the large number of assumptions necessary in traditional models. This approach was attempted for two values of the exponent of the mass (0.75 and 1.0), from which a simple linear model (with exponent 1.0) is proposed. This estimates consequences for three different population density classes: rural, semi-urban (or industrial) and urban. The distribution of the number of fatalities relative to the estimated average number of fatalities was found to approach an S-shaped distribution function. A simple distribution function gives, however, results comparable to the more complex form. For the particular case of assessing the risk of transportation of chlorine by rail in U.S.A. the fatality index model seems to be less conservative, and closer to empirical observations than the traditional models.

EXPLORING ENVIRONMENTAL EFFECTS OF ACCIDENTS DURING MARINE TRANSPORT OF DANGEROUS GOODS BY USE OF ACCIDENT DESCRIPTIONS

On the basis of 1776 descriptions of water transport accidents involving dangerous goods, environmental problems in connection with releases of this kind are described and discussed. It was found that most detailed descriptions of environmental consequences concerned oil accidents, although most of the consequences were described as reversible changes. It was shown that crude oil releases, on average, are approximately five times larger than releases of oil products and that oil product releases are approximately five times larger than other chemicals. Only 2% of the 1776 accidents described contained information on consequences to living organisms, and only 10% contained any information on consequences to ecosystems. A relationship was found between the minimum kilometers of shore polluted and the tonnes released in the case of shore pollution from oil accidents. Oil slicks were shown to be five times longer than broad. Gravity scales used to describe and evaluate environmental consequences were discussed.

Indoor fatal effects of outdoor toxic gas clouds

Abstract Haastrup, P., 1984. Indoor fatal effects of outdoor toxic gas clouds. Journal of Occupational Accidents , 5: 279–290. This paper investigates the indoor effects of an outdoor gas cloud. This is done by using a simple model for transport of toxic gas from outdoor to indoor. The results indicate that while the outdoor effect depends on the product of the cloud passage time and the concentration to some power (e.g. 2.75) the indoor effect of the same cloud depends only on the product of cloud passage time and the concentration. This makes the indoor effect calculation by using models much less sensitive to the outdoor concentration and the power used. The law applies under a wide range of practical conditions.