Abdominopelvic injuries due to road traffic accidents: Characteristics in a registry of 162,695 victims

Objective: Road traffic accidents (RTAs) are the first cause of abdominopelvic injuries (APIs). The objective of this study was to describe the characteristics and severity of APIs due to traffic accidents in a large French trauma registry and to identify risk factors for API.

Methods: All victims from the French Rhône registry of victims of RTAs were analyzed from 1996 to 2013. This registry contained data that were issued over a 20-year period from 245 medical departments, from prehospital care until re-adaptation, and forensic medicine departments. All APIs, defined as an injury between the diaphragm and the pelvic bone, were extracted and studied.

Results: Among 162,695 victims, 10,165 had an API (6.7%). Accidents frequently involved young men and 2 cars. Mean Injury Severity Score (ISS) was 8.7. Mortality rate was 5.6%. Soft tissue injuries largely predominated (n = 6,388; 54.4% of patients). Overall, 2,322 victims had a pelvic bone injury. Internal abdominal organs were involved in 2,425 patients; the most frequent were the spleen, liver, and kidney. Wearing of the seat belt appeared to be a significant protective factor in API, including serious injuries. A partial analysis over the past 2 years among the most severe patients hospitalized in the intensive care unit indicated that nonoperative management was carried out in two thirds of the wounded. In uni- or multivariate analysis, sex, age, type of user, antagonist, time of occurrence, associated severe lesions, or wearing of the seat belt were statistically associated with the occurrence of API, highlighting a more dangerous user profile.

Conclusions: Abdominopelvic injuries concern a minority of road traffic injuries, but they are responsible for significant mortality. Large solid organs are the most frequently affected. Women drivers wearing a seat belt and driving in town during the day appear to be more protected against API.     

天然气管道不同孔径泄漏失效概率量化方法研究*

为研究不同孔径泄漏下天然气管道失效概率,首先基于EGIG数据库和UKOPA数据库天然气管道历史失效数据,计算由不同失效原因导致3种孔径泄漏所占比例;然后将我国管道各原因基础失效概率按照对应比例分别进行修正,获得较适用于我国天然气管道特点的不同孔径泄漏基础失效概率;最后分别考虑第三方破坏、腐蚀、施工缺陷/材料失效、误操作、自然力破坏5种失效原因,完成对天然气管道不同孔径泄漏基础失效概率的修正计算。研究结果表明:小孔泄漏、中孔泄漏和破裂泄漏的基础失效概率分别为0.173,0.128,0.048次/（103 km·a）;修正因子包括管径、埋深、壁厚、管龄、防腐层类型、管道所处区域,上述因子能够满足不同场景下天然气管道失效概率的修正计算;概率量化方法综合考虑失效原因、泄漏孔径以及管道本体信息,能够定量化预测天然气管道失效概率,为天然气管道定量风险评价提供数据支撑。     

Analyzing the Effects of Groundwater Pumping on an Urban Stream‐Aquifer System

When the cone of influence of a pumping well reaches a nearby river, the resulting hydraulic gradient can induce enhanced seepage of streamflow into the aquifer. The rate of seepage is often modeled using analytical solutions that are simple to apply but may not reproduce field data due to mathematical assumptions not being met in the field. Furthermore, the appropriateness of such models has not been investigated in detail due to difficulty in measuring streamflow loss in the field. In this study, a field experiment was conducted on a reach of the South Platte River near Denver, Colorado to estimate pumping‐induced streamflow loss. A network of stream gauges, monitoring wells, and in situ measurements was used to observe streamflow rates, groundwater levels, and temperature to assess if pumping wells have a significant impact on streamflow, and to compare observed streamflow depletion against analytical solutions. Data collected suggest that pumping wells have a noticeable impact on streamflow. The analytical solutions proved accurate if streamflow was low and constant but performed poorly if streamflow was high and variable. Therefore, for this reach, the use of analytical solutions to predict streamflow may only be appropriate under low‐flow, constant‐flow conditions. Methods and results can be used to guide other streamflow depletion studies and to inform cases of pumping‐induced streamflow depletion, particularly in regard to water rights.     

突发性环境污染事故的应急监测探讨

突发性环境污染事故应急预案方案中主要包括污染物的应急监测以及污染事故的处置方案。其中应急监测的工作在于明确造成环境污染的化学物品的种类、浓度、数量、已造成污染范围、已造成的破坏程度、事故未来发展事态等。通过应急监测所整理的信息数据,应急预案组织工作小组可以迅速的对突发性环境污染事故做出科学合理的决策。本文针对突发性环境污染事故应急监测工作方案进行梳理总结,指导组织管理人员如何快速的组织应急监测工作。     

Shelter-in-place risk assessment for high-pressure natural gas wells with hydrogen sulphide and its application in emergency management

This paper provides a risk assessment method of sheltering in-place for high-pressure natural gas wells with hydrogen sulphide. In this paper, the shelter-in-place risk is estimated by integrating the health consequences of an individual taking one kind of emergency response to the emergency orders of sheltering in place from the emergency decision makers and the probability of the corresponding emergency response action. The probability of the corresponding emergency response action in the proposed method is estimated through the accident probability analysis and the probability analysis of taking a certain response action. The health consequence estimation is based on air exchange rate test of the shelter buildings as well as accident consequence calculation. The evaluation of shelter-in-place risks based on “as low as reasonably practicable (ALARP)” guidelines was employed to provide suggestions for emergency management under both normal conditions and off normal conditions. A case study of risk assessment of sheltering in the local residential houses in Xuanhan County of Sichuan Province, China was taken as an example to illustrate the proposed risk assessment process of shelter-in-place and its application in the decision-making process for emergency management.     

Safety evaluation of different acids in high-density polyethylene container loading

To reduce costs, high-purity chemical suppliers wash and reuse HDPE containers collected from users. To determine the lifetime of a container, the appearance of that container and the manufacturer's recommendations for its lifetime are generally considered. Guidelines for determining the lifetime of an HDPE container have not been clearly defined. The lack of these specifications may result in the leakage of high-purity chemicals in the storage, transportation and use of HDPE containers. To understand the effects of using high-purity chemicals (sulfuric acid (H₂SO₄) and nitric acid (HNO₃)) on HDPE, this study revealed its effects by mechanical and thermal performance tests. According to the mechanical properties test results, the ductility and tensile strength of HDPE soaked H₂SO₄ and HNO₃ decreased. HDPE immersed in HNO₃ exhibited the lowest thermal stability by thermal performance testing. In summary, the degradation of HDPE is affected by storage conditions. For this study, HDPE only needs 60 days of immersion in HNO_3, and its ductility and tensile strength will decline obviously. This study shows that when these containers are used for long-term storage of high purity chemicals, the mechanical properties (including ductility, ductility, and tensile strength) of HDPE containers tend to decrease. To decrease accidental leakage of chemicals due to aging of HDPE, comprehensive and approved regulations should be established for the loading, transport, and storage of HDPE containers.     

Simulation analysis of fire truck scheduling strategies for fighting oil fires

Emergency response is an important measure to reduce the loss of any major fire and prevent its escalation. There may be many fire trucks participating in the fire-fighting at the same time, and the scheduling of them will affect the fire-fighting efficiency and thus, capacity. This work focuses on the cycle process of fighting fire and refilling water of fire trucks, and analyzes and compares the scheduling strategies of the fire trucks. The simulation tool eM-plant is utilized to model the fire-fighting process. In view of the emergency response in relation to a chemical fire accident and to prevent its escalation, strategies in the analysis consider the allocation of fire trucks according to the distance of hydrants, the distribution of fire trucks according to the number of fire hydrants, etc. The results of this paper show that an even distribution of fire trucks leads to a good performance, but can be further adjusted to find a more optimal strategy. This study provides guidance for fire truck scheduling in case of emergency response.     

Mutual effects between dynamic leakage behavior and the pressure/temperature in a LNG tank with external heat fluxes

The objective of this work is to investigate and model the mutual effects between the dynamic pressure/temperature in the LNG tank and the leakage behavior with external heat fluxes. The results suggest that the pressure and temperature in tank during leakage change with the comparison results between the heat flux consumed in liquid boil-off and the external heat flux supplied. At the liquid leakage stage, when the external heat flux is not very high, the pressure in tank tends to increase significantly, even results in tank explosion. It increases more and more heavily with higher and higher external heat fluxes. At the vapor leakage stage, large amount of vapor spray out, which results in a high generation rate of vapor by the liquid boil-off. The pressure in tank normally decreases to be low, which is unfavorable for the LNG tank explosion. Therefore, at this vapor leakage stage, blocking the leakage hole as soon as possible is not always a right choice for fire fighters. Finally, it is suggested that reducing the heat flux into the tank, either at the liquid leakage stage or in vapor one, is key to the tank safety.     

PDE accident model from a safety information perspective and its application to Zhangjiakou fire and explosion accident

Accident models can provide theoretical frameworks for determining the causes and mechanisms of accidents, and thus are theoretical bases for accident analysis and prevention. The role of safety information in accident causation is profound. Thus, safety information is an important and essential perspective for developing accident models. This study presents a new accident model developed from a safety information perspective, called the Prediction—Decision—Execution (PDE) accident model. Because the PDE accident model is an emerging accident model that was proposed in 2018, its analysis logic and viability remain to be discussed. Thus, the main contributions of this study include two aspects: (i) detailed explanation of the analysis logic of the PDE accident model, and (ii) case-study examination of the Zhangjiakou fire and explosion accident, a serious accident that occurred in China in 2018, to demonstrate the viability of the PDE accident model. Results show that this is a safety-information-driven accident model that can provide a new and effective methodology for accident analysis and prevention, and safety management.     

Accident consequence calculation of ammonia dispersion in factory area

With the widespread use of ammonia in the process industry, more and more accidents were caused by ammonia leakage and dispersion. The dispersion of ammonia is determined by its physical properties, release source conditions and atmospheric environment. Full-scale numerical simulation based on CFD theory was carried out to study the dispersion law of ammonia in a food factory. It was found that ammonia concentrated on the symmetric plane and showed an upward movement near the source. Moreover, the effect of pressure on the dispersion of ammonia was explored showing that the concentration of ammonia near the source increased with the increase of pressure, while the dispersion of ammonia far from the source is mainly influenced by wind field. Last but not the least, the dangerous area completely covers the obstacle region according to the harmful concentration, but the lethal concentration range and explosion range both only existed near the release source. Correspondingly, the concentration of ammonia in the region far from the symmetric plane can be regarded as a safe area. When the accident happens, one should stay away from the release source and evacuate towards the sides in a timely manner. We hope that this work can provide an effective method in predicting the impact of ammonia dispersion and can arouse concerns over the public safety.