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91.
Posted speed limit and police-reported injury codes are commonly used by researchers to approximate vehicle impact and occupant injury severity. In-depth crash investigations, however, produce more precise measures of crash and injury severity: change in velocity (delta-V) for crash severity and Abbreviated Injury Scale (AIS) scores for injury severity. A comparison of data from police crash reports with that gathered by National Automotive Sampling System (NASS) investigators highlighted the inadequacy of speed limit and police injury codes as proxies for delta-V and AIS injury severity. In general, delta-V increased with speed limit and higher values of AIS were associated with higher police-coded injury severity, but there were a number of anomalies. In particular, 49% of the drivers coded by police as having incapacitating injuries actually had sustained no more than minor injuries. This overstatement of injury severity was less frequent among male (44%) and elderly (37%) drivers than among female (53%) and nonelderly (50%) drivers. Also, 79% of the investigated vehicles that crashed on roads posted at 60 mph (96 km/h) or higher experienced a delta-V less than 25 mph (40 km/h). Safety studies depending on data from only police reports to establish injury or crash severity therefore could produce erroneous results.  相似文献   
92.
93.
The paper describes a programme to develop the profile of major accident risk across a large multi national oil company. It describes the concepts, tools and processes for constructing the risk profile and some of the key learnings from the exercise.  相似文献   
94.
The present study developed a nomological network that theoretically linked time urgency to related variables. To test the proposed relationships, time urgency, achievement strivings (AS), and impatience/irritability (II) were utilized as predictors of health and performance 18 months later. Multivariate canonical correlation analyses provided support for a complex nomological network among the predictors and the outcome measures. Redundancy coefficients and a rotated structure matrix were employed to identify two significant dimensions, labeled crammers and organizers, that linked the predictors with the outcome measures. The results also indicated that the time urgency subcomponents were differentially related to several health outcomes. These findings provide further validity evidence for the time urgency construct, and they suggest that time urgency variables should be considered as important predictors of both health and performance outcomes. Directions for future research on time urgency are discussed. © 1998 John Wiley & Sons, Ltd.  相似文献   
95.
The purpose of this review was to summarize the literature on occupational, acute, traumatic hand injury and suggest directions for future research. In 1996, the leading occupational injury treated in United States' hospital emergency departments was an acute hand injury (e.g. laceration, crush or fracture). These injuries affected 30% of an estimated 3.3 million injured workers (990,000). Cuts and lacerations of the fingers ranked third after back and leg strains in the number of lost workday cases in the USA in 1994. The incidence rate of hand injuries studied in seven manufacturing environments around the world ranged from 4 to 11 per 100 workers per year. Workers aged 24 years or less had the highest risk of hand injury. Men had higher rates of severe hand injury than women.Despite the high frequency and significant amount of lost work time associated with these injuries, they are poorly understood from an etiological perspective. There is only one case-control study of occupational hand injury in the literature. That study suggested an important role for both fixed (age) and transient risk factors (doing an unusual task) at the time of the injury. More analytic epidemiological research is needed to identify potentially modifiable risk or protective factors (e.g. glove use) for acute hand injuries. In this regard, the case-crossover design, a relatively new epidemiological approach using cases as their own controls, could prove an efficient method for determining transient, modifiable risk factors for acute, occupational hand injury.  相似文献   
96.
In order to evaluate the leading and lagging effects of process safety climate on incidents, we correlated safety climate survey data with organizational safety records from before and after the survey time period. We obtained data from a large, multinational organization with manufacturing operations involving a number of complex processes, chemicals, and hazardous substances. A total of 7728 employees from 62 sites responded to a safety climate survey in 2007. Individual responses were aggregated to the site-level and matched to site-level organizational records of process safety incidents 1 year before and 1 year after survey administration. Employees’ perceptions of good routine housekeeping were significantly related to environmental impact incidents as both a leading and a lagging indicator, as well as fires/explosions and property damage outcomes. Employees’ perceptions of systems to prevent backlogs and the extent to which health and safety problems are promptly corrected were also related to environmental releases and fires/explosions. Implications for process safety climate research, organizational survey strategies, and organizational climate change are discussed.  相似文献   
97.
Twenty-five years of HAZOPs   总被引:7,自引:0,他引:7  
The HAZOP or hazard and operability study was developed by ICI over 25 years ago and is in wide use today throughout the world. The technique is intended to review, in a formalized manner, the design of a system such as a chemical process production plant to detect potential problems in the operation of the system. The system has been extended for use on all types of production, storage and distribution units. Experience in the use of hazard studies has lead to the development of a phased approach with three distinct design phases.  相似文献   
98.
Motorcycles are overrepresented in fatal motor vehicle accidents: The death rate for motorcycle riders of about 35 per 100,000,000 miles of travel compares with an overall vehicle death rate of 2.57 per 100,000,000 miles. In the attempt to reduce the frequency of automobile-motorcycle collisions, numerous studies have manipulated motorcycle and motorcyclist characteristics to enhance conspicuity. In this paper, we give a review of studies that examined the effectiveness of these measures. Subsequently, we take a critical look at the methods used in these studies to evaluate the effectiveness of conspicuity treatments. Furthermore, we identify factors yet to be considered in the empirical research in this area that may contribute to collisions with motorcycles. These include information-processing failures at the identification and decision stage, as well as more or less permanent factors potentially responsible for different information-processing failures. Transient factors related to the failure to detect motorcycles might include alcohol, fatigue/lack of sleep, inattention, and information overload, whereas more permanent factors might include “cognitive” conspicuity and fi eld dependence.  相似文献   
99.
OBJECTIVE: The primary objective of the study was to determine if drinking patterns on the days immediately prior to an alcohol-related motor vehicle crash (ARMVC) were significantly different than drinking patterns in the weeks prior to the crash. METHODS: Following ARMVC, 187 hospitalized non-alcohol dependent young-adults (43 females, 144 males) were enrolled. Mean age was 29.03 years, mean blood alcohol level was 165.18 mg/dL, and mean injury severity score was 10.50. When alcohol-free, subjects were interviewed by nurse clinicians to determine the quantity/frequency of alcohol consumption during the 28 days prior to the crash. Subjects reported the number of standard drinks using the Timeline Followback procedure. Total drinks/day were determined, with day 1 considered 4 weeks prior to the crash and day 28 the day of the crash. A random-intercepts general linear mixed model (GLMM) was used to test the effect of several covariates (segment 1 [days 1-26], segment 2 [days 27-28], age, sex, race, holiday/non-holiday period, driver/passenger status, and weekend/weekday crash) on the amount of standard drinks/day. RESULTS: There was no significant interaction among the covariates. The only significant predictors of drinks/day were segment 2 (b = .322, p < .0001) and gender (b = -.221, p = .016). The positive, statistically significant slope for segment 2 indicated an increase in consumption of drinks/day in the two-day period prior to the ARMVC and the negative slope for gender indicated greater consumption of drinks/day for men than women. CONCLUSION: Persons injured in an ARMVC had a significant increase in alcohol consumption on the day before and the day of vehicular crashes (days 27 and 28) as compared to the first 26 days in the 28-day period preceding the crash. When non-alcohol-dependent subjects are counseled to reduce their risk of traffic crashes, they should be alerted that when their patterns of drinking change, they are at higher risk than usual for a crash.  相似文献   
100.
This paper describes the results of the first experimental stage of Phase IV of a Joint Industry Project (JIP) on liquid jets and two-phase droplet dispersion. The objective of this stage of the JIP was to generate experimental rainout data for non-flashing water and xylene experiments. See the overview companion paper I for a wider overview of the problem, model implementation and associated model validation.A range of orifice sizes (2.5 and 5 mm) and stagnation pressures (4–16 barg) were applied. Measurements included flow rate, initial droplet size, plume concentrations/temperatures for a range of downstream locations, and distributed rainout.Instead of the Phase Doppler Anemometry method used for droplet size measurements earlier in the JIP, a photographic technique was applied in an attempt to include measurement of the larger (non-spherical) droplets. This enabled a more accurate evaluation of the initial droplet size distribution and a much clearer understanding of the droplet morphology. The results showed that the droplet behaviour in the jet is more complex than had been anticipated with the mass distribution dominated by a very small number of large non-spherical droplets. Consequently a large number of spray images were required to evaluate an accurate size distribution.Distributed rainout was measured by weighing the amount of rainout in trays positioned along the jet direction. The rainout results showed a good degree of repeatability and internal consistency. They indicated that an increasing proportion of the released material did not rainout for increasing pressure. Rainout distance also increased with increasing pressure. Evaporation of the liquid was confirmed by temperature measurements, which showed the effect of evaporative cooling.Xylene concentration measurements (up to 1%) were carried out using a direct reading photoionization detector calibrated for xylene (measuring vapour only). For a limited dataset, the accuracy of these measurements was estimated by means of comparison against an alternative more time-consuming concentration method (xylene absorption onto a charcoal filter; measuring both vapour and liquid). The concentration measurements displayed several consistent qualitative features. For example, at a given downstream distance, the peak concentration increases with increasing pressure and nozzle diameter and the vertical height at which the peak is achieved increases. The cross-stream profiles displayed a consistent tendency to increased concentration at the edge of the jet, and the reason for this has not been established.Finally recommendations are provided for potential future work.  相似文献   
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