A capping technique for emergency response in offshore blowout accidents

Capping stack is an emergency shut-in technique that can effectively control offshore blowout accidents. This technique stemmed the spilled oil well (Macondo) in 2010 Deepwater Horizon blowout accident. However, few efforts have been devoted to studying the way to efficiently and safely conduct the operation of capping stack. In this paper, program evaluation and review technique (PERT) was employed to quantitatively design the operation procedure of capping stack. A mechanical model was established to determine the configuration scheme of capping stack. And a sensitivity analysis of operational factors of capping stack was conducted through orthogonal tests. Experimental results recommend to optimize the operation process by reducing the working time of diamond cutting tool down-pass, Lower Marine Riser Package (LMRP) upper riser incision, LMRP and original Blowout Preventer (BOP) separation, and LMRP recovery, in order to guarantee that the whole operation can be completed as scheduled. The results show that the number of ram BOPs has little effect on the equivalent stress of conductors. To improve system reliability, a five-ram capping stack is recommended to be applied in the defined accident scenario. The maximum equivalent stress of conductors rates the drilling vessel offset as the primary factor, followed by shut-in pressure, ocean current and top tension. The drilling vessel offset needs to be given the priority control and the shut-in pressure should be jointly monitored.     

我国劳动安全监察机构设置探讨与遏制事故的建议

本文运用实践中的实例，阐述了我国劳动安全监察机构设置中存在的问题和多头分散的安全管理所带来的弊端，呼吁顺应市场经济的发展和伤亡事故多发的趋势，尽快建立一个独立于生产部门的、具有第三者身份的、由国家垂直领导与管理的安全监督检查管理机构，遏制不断上升的事故趋势。     

Risk of motor vehicle accident death among 1.3 million veterans of the Iraq and Afghanistan wars

Objective: We conducted a cohort study of recent wartime veterans to determine the postservice mortality risk due to motor vehicle accidents (MVAs).

Methods: Veterans were identified from the Defense Manpower Data Center records. Deployment to te Iraq or Afghanistan war zone was determined from the Contingency Tracking System. Vital status of 317,581 deployed and 964,493 nondeployed veterans was followed from their discharge dates between 2001 to 2007 until earlier of date of death or December 31, 2009. Underlying causes of death were obtained from the National Death Index Plus.

Results: Based on 9,353 deaths (deployed, 1,650; nondeployed, 7,703), of which 779 were MVA deaths as drivers (166; 613), both cohorts had 25 to 24% lower mortality risk from all causes but had 44 to 45% higher risk of MVA deaths relative to the U.S. general population. The higher MVA mortality risk was not associated with deployment to the war zone. After controlling for age, sex, race, marital status, branch of service, and rank, the risk for deployed veterans was comparable to that of nondeployed veterans (hazard ratio = 0.91; 95% confidence interval, 0.77–1.09).

Conclusions: Veterans exhibit significantly higher risk of MVA deaths compared to the U.S. general population. However, deployment to the Iraq or Afghanistan war was not associated with the excess risk.     

Evaluating the Brazilian zero tolerance drinking and driving law: Time series analyses of traffic-related mortality in three major cities

Objective: A zero tolerance alcohol restriction law was adopted in Brazil in 2008. In order to assess the effectiveness of this intervention, the present study compares specific mortality in 2 time series: 1980–2007 and 2008–2013.

Methods: Data on mortality and population were gathered from official Brazilian Ministry of Health information systems. Segmented regression analyses were carried out separately for 3 major Brazilian capitals: Belo Horizonte, Rio de Janeiro, and São Paulo.

Results: In 2 cities (Belo Horizonte and Rio de Janeiro) there were no significant changes in mortality rate trends in 2 periods, 1980 to 2007 and 2008 to 2013, where the observed rates did not differ significantly from predicted rates. In São Paulo, a decreasing trend until 2007 unexpectedly assumed higher levels after implementation of the law.

Conclusion: There is no evidence of reduced traffic-related mortality in the 3 major Brazilian capitals 5.5 years after the zero tolerance drinking and driving law was adopted.     

Analyzing injury severity factors at highway railway grade crossing accidents involving vulnerable road users: A comparative study

Objective: The main objective of this study is to identify the main factors associated with injury severity of vulnerable road users (VRUs) involved in accidents at highway railroad grade crossings (HRGCs) using data mining techniques.

Methods: This article applies an ordered probit model, association rules, and classification and regression tree (CART) algorithms to the U.S. Federal Railroad Administration's (FRA) HRGC accident database for the period 2007–2013 to identify VRU injury severity factors at HRGCs.

Results: The results show that train speed is a key factor influencing injury severity. Further analysis illustrated that the presence of illumination does not reduce the severity of accidents for high-speed trains. In addition, there is a greater propensity toward fatal accidents for elderly road users compared to younger individuals. Interestingly, at night, injury accidents involving female road users are more severe compared to those involving males.

Conclusions: The ordered probit model was the primary technique, and CART and association rules act as the supporter and identifier of interactions between variables. All 3 algorithms' results consistently show that the most influential accident factors are train speed, VRU age, and gender. The findings of this research could be applied for identifying high-risk hotspots and developing cost-effective countermeasures targeting VRUs at HRGCs.     

Understanding the patterns and characteristics of Natech events in China

With the frequent occurrence of natural disasters, natural hazard triggered technological accident (Natech) risk has attracted extensive attention from academia and industry. Natech events have the characteristics of various inducements and consequences, cascading chain reactions, and complex spatial interleaving, which leads to serious consequences. The Natech event is constantly threatening China's industrial safety production. However, the systematic analysis of Natech events in China is still lacking. The study counted 288 cases in the past 20 years and constructed Natech databases. Based on the theory of risk chain and risk system, a systematic horizontal and vertical analysis was developed for the first time. It aims to understand the characteristics of Natech events in terms of temporal and spatial, hazard factors, industry and risk material, consequences and hazard. In the results, Natech events showed a fluctuating trend. The southwest region (28.13%) and the middle Yellow River region (21.18%) belong to the critical control areas. China's industries were seriously affected by the disasters of meteorological (43.75%) and secondary, especially in the Chemical & Petrochemical and manufacturing. 64.58% of Natech events caused environmental pollution, and 13.19% of Natech events caused major or above consequences. Oil (31.25%) and hazardous chemicals (28.47%) were the main substances causing pollution, fire and explosion, which need to be controlled. The research preliminarily clarifies the risk chain and characteristics of Natech events, which provided the basis for Natech risk assessment.     

Occupational injuries of immigrant and Finnish bus drivers

Problem

With baby boomers reaching retirement age, Western countries may need more immigrant workers to ensure productivity. Many studies have suggested a higher occupational injury frequency among immigrant workers, which could considerably reduce their contribution to society. The aim of this study was to examine whether immigrant workers have a higher injury frequency compared to Finnish workers when performing the exact same tasks under the same working conditions.

Method

A total of 176 Finnish and 130 immigrant bus drivers were asked about their occupational injuries during the past 12 months via a questionnaire. In addition, the data contained 134 injuries reported by the transport firm to an insurance company.

Results

There was no significant difference in reporting occupational injuries by self-reporting or by company-records. Because there were more accident-repeaters among Finnish drivers, their injury frequency (114) was higher than that of immigrant drivers (78).

Application/Impact

This study showed that immigrant workers did not have a higher injury frequency than other workers when they worked in the exact same conditions. Immigrant workers can work as safely as native-Finnish workers, when their working conditions and job contracts are at the same level as those of the original population. Immigrant workers can compensate for the shortage of workforce caused by an aging population.     

硫化油生产过程的活性反应危害识别与评估

利用差示扫描量热仪（DSC）、反应量热仪（RC1和快速筛选仪（RSD）等仪器设备,对硫化油合成过程的热特征和压力特征进行系统研究,发现该反应为微吸热的过程,但仍应严格控制工艺参数,如压力、温度等。防止反应器中混入水等低沸点物质,导致容器超压。反应器内避免混入空气、硝酸等禁忌物料,防止因活性反应而引发灾害性燃爆事故。     

江苏省饮用水水源地突发环境事件分析及对策建议

分析了近年来江苏省几起典型的饮用水水源地突发环境事件及其特点,指出,结构性、布局性突发环境事件风险突出,交通运输带来的环境风险仍在凸显,企业非法排污产生的环境风险不小,饮用水水源地监测预警手段不足,联合治水模式尚未形成,流域性环境风险防控机制尚未建立。提出,应开展饮用水水源地突发环境事件风险评估,健全突发环境事件监控预警网络,健全饮用水水源地突发环境事件联防联控机制,加强饮用水水源地突发环境事件应急处置技术研究,加快产业机构调整和备用水源地建设。     

固相微萃取技术在苯胺等突发性水环境污染事故中的应用

建立了固相微萃取与车载气相色谱-质谱联用技术现场快速定量分析突发性水环境污染事故中的硝基苯、苯酚、苯胺3种半挥发性有机物的方法。选用PA萃取纤维,调节水样p H为8.5,加入30%的氯化钠,45℃顶空萃取30 min可得最佳萃取效果。在最佳实验条件下,硝基苯、苯酚、苯胺的方法检出限分别为0.68、3.2、4.88μg/L;平行测定7次的相对标准偏差分别为5.37%、8.31%、2.86%;3种化合物的相关性系数均大于0.99;对实际样品测定的加标回收率在61.1%~120%。