ARAMIS project: a comprehensive methodology for the identification of reference accident scenarios in process industries

In the frame of the Accidental Risk Assessment Methodology for Industries (ARAMIS) project, this paper aims at presenting the work carried out in the part of the project devoted to the definition of accident scenarios. This topic is a key-point in risk assessment and serves as basis for the whole risk quantification.

The first result of the work is the building of a methodology for the identification of major accident hazards (MIMAH), which is carried out with the development of generic fault and event trees based on a typology of equipment and substances. The term “major accidents” must be understood as the worst accidents likely to occur on the equipment, assuming that no safety systems are installed.

A second methodology, called methodology for the identification of reference accident scenarios (MIRAS) takes into account the influence of safety systems on both the frequencies and possible consequences of accidents. This methodology leads to identify more realistic accident scenarios. The reference accident scenarios are chosen with the help of a tool called “risk matrix”, crossing the frequency and the consequences of accidents.

This paper presents both methodologies and an application on an ethylene oxide storage.     

Effect of consecutive driving on accident risk: A comparison between passenger and freight train driving

This study combined driver-responsible accidents with on-board driving hours to examine the effect of consecutive driving on the accident risk of train operations. The data collected from the Taiwan Railway Administration for the period 1996–2006 was used to compute accident rates for varied accumulated driving hours for passenger and freight trains. The results showed that accident risk grew with increased consecutive driving hours for both passenger and freight trains, and doubled that of the first hour after four consecutive hours of driving. Additional accident risk was found for freight trains during the first hour due to required shunting in the marshalling yards where there are complex track layouts and semi-automatic traffic controls. Also, accident risk for train driving increased more quickly over consecutive driving hours than for automobile driving, and accumulated fatigue caused by high working pressure and monotony of the working environment are considered to be the part of the reason. To prevent human errors accidents, enhancing safety equipment, driver training programs, and establishing a sound auditing system are suggested and discussed.     

Rearward-facing child seats--the safest car restraint for children?

During recent years the use of child restraints in cars in Sweden has rapidly increased. The fact that the different restraint systems prevent injuries has been substantiated, as is shown in this paper. The major emphasis is put on the benefits of using rearward-facing child seats for children 0 to 4 years of age. Attitudes concerning child safety in cars and the misuse problem are also discussed. Based on Volvo's accident material it is shown that the injury-reducing effect of the rearward-facing child seat is superior to all present types of child restraints in cars. This paper is mainly based upon Volvo's own traffic accident material. This paper is based upon accidents that occurred between the years 1976 and 1988 and comprises some 13,000 accidents involving approximately 22,000 people. In 1,500 of these accidents at least one child (0 to 14 years) was present in the vehicle. In addition to the collection of accident data, separate attitude studies have been carried out, concerning child safety in cars.     

Disaggregate analysis of road accident severities

A comprehensive understanding of the relationship between road accident occurrence and severity of consequences permits the formulation of safety measures that are most cost-effective. A disaggregate model of road accident severity based on sequential logit models is presented. The sequential binary approach is able to account for the dependency between different levels of severity. Factors that affect the level of damage experienced by individuals involved in road accidents include: accident dynamics, seating position, vehicle condition, vehicle size, driver condition and driver action. Separate models are calibrated for three accident situations: single-vehicle accidents, two-vehicle accidents and multi-vehicle accidents. Ontario road accident police reports are used to calibrate and validate the models. The results of a simple application of the models to a safety protocol involving the effectiveness of passenger restraint devices is presented.     

Risk factors affecting the severity of single vehicle traffic accidents in Hong Kong

A population-based case-control study was conducted to examine factors affecting the severity of single vehicle traffic accidents in Hong Kong. In particular, single vehicle accident data of three major vehicle types, namely private vehicles, goods vehicles and motorcycles, which contributed to over 80% of all single vehicle accidents during the 2-year-period 1999-2000, were considered. Data were obtained from the newly implemented traffic accident data system (TRADS), which was developed jointly by the Transport Department, Police Force and Information Technology Services Department, Hong Kong. The effect of district, human, vehicle, safety, environmental and site factors on injury severity of an accident was examined. Unique risk factors associated with each of the vehicle types were identified by means of stepwise logistic regression models. For private vehicles, district board, gender of driver, age of vehicle, time of the accident and street light conditions are significant factors determining injury severity. For goods vehicles, seat-belt usage and weekday occurrence are the only two significant factors associated with injury severity. For motorcycles, age of vehicle, weekday and time of the accident were determined to be important factors affecting the injury severity. Identification of potential risk factors pertinent to the particular vehicle type has important implications to relevant official organisations in modifying safety measures in order to reduce the occurrence of severe traffic accidents, which would help to promote a safe road environment.     

Risk factors associated with traffic violations and accident severity in China

With the recent economic boom in China, vehicle volume and the number of traffic accident fatalities have become the highest in the world. Meanwhile, traffic accidents have become the leading cause of death in China. Systematically analyzing road safety data from different perspectives and applying empirical methods/implementing proper measures to reduce the fatality rate will be an urgent and challenging task for China in the coming years. In this study, we analyze the traffic accident data for the period 2006–2010 in Guangdong Province, China. These data, extracted from the Traffic Management Sector-Specific Incident Case Data Report, are the only officially available and reliable source of traffic accident data (with a sample size >7000 per year). In particular, we focus on two outcome measures: traffic violations and accident severity. Human, vehicle, road and environmental risk factors are considered. First, the results establish the role of traffic violations as one of the major risks threatening road safety. An immediate implication is: if the traffic violation rate could be reduced or controlled successfully, then the rate of serious injuries and fatalities would be reduced accordingly. Second, specific risk factors associated with traffic violations and accident severity are determined. Accordingly, to reduce traffic accident incidence and fatality rates, measures such as traffic regulations and legislation—targeting different vehicle types/driver groups with respect to the various human, vehicle and environment risk factors—are needed. Such measures could include road safety programs for targeted driver groups, focused enforcement of traffic regulations and road/transport facility improvements. Data analysis results arising from this study will shed lights on the development of similar (adjusted) measures to reduce traffic violations and/or accident fatalities and injuries, and to promote road safety in other regions.     

Bus accident analysis of routes with/without bus priority

This paper summarises findings on road safety performance and bus-involved accidents in Melbourne along roads where bus priority measures had been applied. Results from an empirical analysis of the accident types revealed significant reduction in the proportion of accidents involving buses hitting stationary objects and vehicles, which suggests the effect of bus priority in addressing manoeuvrability issues for buses. A mixed-effects negative binomial (MENB) regression and back-propagation neural network (BPNN) modelling of bus accidents considering wider influences on accident rates at a route section level also revealed significant safety benefits when bus priority is provided. Sensitivity analyses done on the BPNN model showed general agreement in the predicted accident frequency between both models. The slightly better performance recorded by the MENB model results suggests merits in adopting a mixed effects modelling approach for accident count prediction in practice given its capability to account for unobserved location and time-specific factors. A major implication of this research is that bus priority in Melbourne's context acts to improve road safety and should be a major consideration for road management agencies when implementing bus priority and road schemes.     

Hazard-Based Design of the Bow-Tie Method to Prevent and Mitigate Mine Accidents

The mining trade involves many complicated and interrelated variables—its complex environment, abundant machinery and a plethora of other contributors to accidents. In both developed and developing countries, mining accidents have caused many casualties. However, a universal risk assessment method for mining accidents is has not yet been implemented. Among risk assessment methods, the bow-tie has been used in different industry processes and systems and has proven effective. In this paper, the bow-tie model is utilized to investigate the relationship among mining accident risks, safety measures and possible consequences. The paper illustrates the hazards of mining accidents using US mine accident data. It also shows how the consequences of mine accidents are summarized by laws and regulations of different countries. This paper also introduces a series safety measures from Chinese safety standards and how the safety measures prevent and mitigate risks. At the end of the paper, a case of mine water inrush is applied using the bow-tie approach. The results show that the method is effective for analyzing mine safety.     

Multiple-vehicle traffic accidents in Hong Kong

‘Multiple-vehicle traffic accident’ refers to a crash between two or more moving objects. Unlike single-vehicle accidents, not all drivers involving in a multiple-vehicle accident are responsible for the occurrence of the event. Accordingly, variables such as road type, speed limit and number of vehicles involved in the accident are expected to play a much more important role in association with injury severity in multiple-vehicle accidents. To study the factors influencing injury severity of multiple-vehicle traffic accidents, a population-based study was conducted. The traffic accident data was obtained from the Traffic Accident Data System (TRADS), which was developed by the Transport Department, Police Force and Information Technology Services Department, Hong Kong. Multiple-vehicle traffic accidents (N = 10,630) occurring during the 2-year period 1999/2000 were considered. Potential risk factors such as district, human, vehicle, safety, environmental and site factors were examined. Categorizing injury severity into “fatal/serious” and “slight”, a stepwise logistic regression model was applied to the population data set. The district board, time of the accident, driver's gender, vehicle type, road type, speed limit and the number of vehicles involved are significant factors influencing the injury severity. Identification of risk factors for severe traffic accidents provides valuable information to help with new and improved road safety control measures.     

Vertebral fractures in motor vehicle accidents–a medical and technical analysis of 33,015 injured front-seat occupants

Spinal injuries pose a considerable risk to life and quality of life. In spite of improvements in active and passive safety of motor vehicles, car accidents are regarded as a major cause for vertebral fractures. The purpose of this study was to evaluate the current incidence of vertebral fractures among front-seat occupants in motor vehicle accidents, and to identify specific risk factors for sustaining vertebral fractures in motor vehicle accidents. Data from an accident research unit were accessed to collect collision details, preclinical data, and clinical data. We included all data on front-seat occupants. Hospital records were retrieved, and radiological images were evaluated.     

ARAMIS project: a more explicit demonstration of risk control through the use of bow-tie diagrams and the evaluation of safety barrier performance

Over the last two decades a growing interest for risk analysis has been noted in the industries. The ARAMIS project has defined a methodology for risk assessment. This methodology has been built to help the industrialist to demonstrate that they have a sufficient risk control on their site.

Risk analysis consists first in the identification of all the major accidents, assuming that safety functions in place are inefficient. This step of identification of the major accidents uses bow–tie diagrams. Secondly, the safety barriers really implemented on the site are taken into account. The barriers are identified on the bow–ties. An evaluation of their performance (response time, efficiency, and level of confidence) is performed to validate that they are relevant for the expected safety function. At last, the evaluation of their probability of failure enables to assess the frequency of occurrence of the accident. The demonstration of the risk control based on a couple gravity/frequency of occurrence is also possible for all the accident scenarios.

During the risk analysis, a practical tool called risk graph is used to assess if the number and the reliability of the safety functions for a given cause are sufficient to reach a good risk control.     

Vehicle deformation patterns in New Zealand road accidents

This paper presents partial results of a study undertaken by the University of Auckland in cooperation with the Ministry of Transport in New Zealand, into vehicle damage characteristics in typical road accidents. The overall objective of the study was to evaluate the likely effect of vehicle damage on child restraint systems installed in vehicles in common use on New Zealand roads. The results presented here, relate specifically to vehicle deformation and encroachment as recorded at the accident scenes by traffic officers over a 3 month period. It would appear from the results of the study involving 406 vehicles, that the likelihood of encroachment into the passenger compartment as a result of an accident, is considerably less for the centre back seat position. This confirms the widely accepted view that it represents the most desirable location for a child safety restraint system with regard to possible injury caused by vehicle deformation.     

Association between major injuries and seat locations in a motorcoach rollover accident

Motorcoaches and buses have the highest accident rate among different kinds of vehicles in Taiwan. It is, therefore, important to modify motorcoach designs so that they increase passenger safety. We collected patient data from a motorcoach rollover accident to assess the major injuries of the passengers and the associated risk factors for each type of injury. The accident occurred on a summer day in 2003 in central eastern Taiwan. A double-decker motorcoach carrying 46 passengers and a driver rolled over onto its left side on a downhill path because the coach's brakes failed. On the upper deck, the coach had four columns of seats, two on either side of a center aisle: 12 pairs on the left side, and 10 pairs on the right. Of the 41 seated people on the upper deck, the passengers in the down side (left seats) of each pair of seats had higher Injury Severity Scores than those in the up side (right seats), and passengers >or=65 years old had relatively higher rates of hemothorax and head injuries with subarachnoid hemorrhage or intracranial hemorrhage than those <65. Multivariate analysis showed that age >or=65 years and sitting on the down side at the time of rollover were independent risk factors for major injuries. Our analysis of the data from this motorcoach rollover accident showed that most major injuries occurred as passengers in the up side seats were thrown from their seats and compressed the neighboring passengers in the down side. We hypothesize that occupant restraint devices, such as seat belts, might prevent or reduce some injuries in motorcoach rollover accidents.     

An ordinal multivariate analysis of accident counts as functions of traffic approach volumes at intersections

This research is concerned with the statistical analysis of accident counts at nonsignalized intersections. The objective is to develop a method for determining general (nonlinear) relationships between approach volumes and accident counts. The method must accommodate the testing of whether intersections of differing physical designs have higher or lower rates of accidents than predicted by traffic levels. It is assumed that only aggregate data are available: (1) counts of total accidents by type (e.g., injury versus property damage) without details concerning the locational position(s) of the vehicle(s) involved; and (2) aggregate traffic intensity on each intersection entry without details concerning turning volumes. The method involves the application of nonlinear multivariate methods to variables treated as ordinal scales. A case study application involving four-leg and three-leg ("T") nonsignalized major arterial intersections in the Netherlands is described. The effect of bicycle traffic on accident rates is included in the case study analysis. The results indicate that there are three groups of each of the two types of intersections based on traffic flow patterns. For each group, a different functional form was found to relate accident rates and specific variables measuring traffic volumes. There were no significant differences among the physical design categories of the intersections in each group that were not accounted for by differences in traffic intensities.     

Accident under-reporting among employees: Testing the moderating influence of psychological safety climate and supervisor enforcement of safety practices

We examined accident under-reporting with data from 425 employees employed in 5 industries with above average risk for employee injuries. We expected that rates for unreported accidents would be higher than rates for reported accidents; and that organizational safety climate and perceptions of supervisor enforcement of safety policies would moderate the relationship between unreported accidents and reported accidents. Results showed that the number of unreported accidents was significantly higher than the number of reported accidents. There was an average of 2.48 unreported accidents for every accident reported to the organization. Further, under-reporting was higher in working environments with poorer organizational safety climate or where supervisor safety enforcement was inconsistent. We discuss the implications of these findings for improving accident under-reporting and occupational safety in the workplace.     

Road traffic accidents in rich developing countries: The case of Libya

Libya is a rich developing country which suffers the consequences of explosions in both human and vehicle population. This has been accompanied by a heavy toll of deaths, In 1977, road accidents were the cause of 10% of all deaths and 62% of male deaths in the age group 15–25. The rates-per hundred million veh km-of fatalities, injuries and accidents (1980) were 35.202 and 416 respectively. The pedestrian fatality and casualty rates (1977) were high (20,134/100,000 population) especially among the old males over 64 (89,384/100,000 population). In the age group 20–24, casualty rate of drivers was 1256/100,000 driver (1977). Accidents were severe as well. Between 1970–1980 accident severity index was increasing with time and almost doubled by the end of the period reaching 13. Road accidents in Libya do not only represent an important social problem but also an economic one. In 1978, accidents cost the country about $160 million. The factors which affect accident rates and severity are divided into behavioural and structural ones and investigated. There is room for improving traffic safety in Libya. A comprehensive traffic safety program is urgently needed.     

Age-related safety in professional heavy vehicle drivers: A literature review

With Australia facing a looming shortage of heavy vehicle drivers the question is raised as to whether it is desirable or prudent to encourage older professional heavy vehicle drivers to remain in the transport sector for longer, particularly those of heavy vehicles or recruit drivers of a younger age.

Aim

To review age-related safety and identify other factors that contribute to accidents experienced by heavy vehicle drivers.

Methods

A search was conducted of national and international peer-reviewed literature in the following databases: MedLine, Embase, Cinahl, PsychInfo and the Canadian Centre for Occupational Health & Safety. A manual search was performed to obtain relevant articles within selected journals.

Results

A limited number of studies reported age-specific accident rates for heavy vehicles for the spectrum of driver age that included drivers younger than 27 years and those over 60 years of age. Heavy vehicle drivers younger than 27 years of age demonstrated higher rates of accident/fatality involvement which decline and plateau until the age of 63 years where increased rates were again observed. Other contributing factors to heavy vehicle accidents include: long hours and subsequent sleepiness and fatigue, employer safety culture, vehicle configuration particularly multiple trailers, urbanisation and road classification.

Conclusions

Drivers of heavy vehicles are over-involved until age 27 years however a characteristic ‘U’ shaped curve indicates a higher risk of accident involvement for both younger and older drivers. More detailed analyses of “at-fault” involvement and inability to avert an accident and other factors that contribute to accidents across the ages of heavy vehicle drivers may give further clarification to the degree of safety of both younger and older commercial heavy vehicle drivers.     

Characteristics of rear-end accidents at signalized intersections using multiple logistic regression model

Multi-vehicle rear-end accidents constitute a substantial portion of the accidents occurring at signalized intersections. To examine the accident characteristics, this study utilized the 2001 Florida traffic accident data to investigate the accident propensity for different vehicle roles (striking or struck) that are involved in the accidents and identify the significant risk factors related to the traffic environment, the driver characteristics, and the vehicle types. The Quasi-induced exposure concept and the multiple logistic regression technique are used to perform this analysis. The results showed that seven road environment factors (number of lanes, divided/undivided highway, accident time, road surface condition, highway character, urban/rural, and speed limit), five factors related to striking role (vehicle type, driver age, alcohol/drug use, driver residence, and gender), and four factors related to struck role (vehicle type, driver age, driver residence, and gender) are significantly associated with the risk of rear-end accidents. Furthermore, the logistic regression technique confirmed several significant interaction effects between those risk factors.     

Chemical Accident Simulation Tool (CAST): A System for Assessing Consequences of Accidents in Chemical Process Industry

The development and validation of a new software named chemical accident simulation tool (CAST) is presented. CAST enables development of scenarios of different types of accidental fires and explosions that can occur in chemical process industry (CPI). CAST is also capable of assessing the likely consequences of such accidents in terms of the area impacted and the types of impacts. The distinguishing features of CAST are (a) it incorporates a larger set of established models than handled by existing packages to simulate a wider variety of accidents in CPI; (b) it is developed with an integrated mapping tool to display damage zones around accident center; this makes the application useful in decision making; and (c) it calculates the results in a fast and reliable manner. Due to these attributes, CAST has increased efficiency, better understanding of the accident scenarios, and better communication of results. Validation of the software has been done with published results which shows that the codes for calculating the impacts from accidents are correct.     

Evaluation and optimization of chromium removal from tannery effluent by microemulsion in the Morris extractor

A multidisciplinary Road Accident Analysis Group with the objective of conducting in-depth investigations of specific types of accidents has existed in Denmark for some years. The group has analysed head-on collisions, left-turn accidents, truck accidents and single vehicle accidents. The data collection included police reports, the group's investigation of accident sites and vehicles involved, and interviews with the involved road users and witnesses. The main accident factors in the head-on collisions and in the single vehicle accidents were excessive speed, drunk driving and driving under the influence of illegal drugs. The primary accident factors in left-turn accidents were attention errors or misjudging the amount of time available to complete the left turn. In the truck accidents insufficient searching for visual information as well as speeding were major factors. For all the accident themes the primary injury factor was failure to wear seat- belts. The multidisciplinary approach has provided a rather precise knowledge of the contributing factors leading up to the accident. The method requires a lot of resources, which is a limiting factor for the number of accidents to be analysed in this way. However, the method is suitable for analysis of common occurring or very serious types of accidents.