Guidance to improve the effectiveness of process safety management systems in operating facilities

The Process Safety Management (PSM) systems at the operating facilities in the Oil & Gas and in Chemical manufacturing industries have matured over the years and have become, at most facilities, very robust and sophisticated. These programs are administrated by Process Safety (PS) teams at both the corporate business units and plant levels and have been effective in reducing the number and severity of PS events across the industries over the past 25 years or so. Incidents however are occurring at a regular interval and in recent times several noteworthy PS events have occurred in the United States which have brought into question the effectiveness of the PSM programs at play. These facilities have been applying their PSM programs with the expectation that the number and severity of PS events would decrease over time. The expected result has not been realized, especially in context to those facilities that have undergone the recent incidents. Current paper reviews a few publicly available PS performance reports of Oil & Gas and Chemical manufacturing industries. The authors identified a few factors at play that have led to these PS events based on their experience, literature review, and incident investigation reports. Most of the factors are intertwined with multiple PSM elements and it requires a holistic approach to address them. Each of the factors is described and the path forward is proposed to improve the effectiveness of PSM programs.     

土地流转与农民收入变化研究

土地流转作为我国农村土地制度改革的重点受到了广泛的关注,但土地流转能否显著增加农民收入,达到改善农村内部收入差距的目的,现有研究并未得到一致结论。本文在文献回顾和总结的基础上,依据中国家庭追踪调查(CFPS)数据,运用倾向值匹配(PSM)方法和基于回归的夏普里值分解(Shapley Value)方法,从收入水平和收入差距两个维度实证分析土地流转对农民收入的影响。研究结果表明:(1)参与土地流转能够显著提高农户家庭收入水平。土地流转使转入户家庭人均总收入和农业收入显著提高18.18%和72.46%,并且大规模转入的农户人均总收入的增加程度显著高于小规模转入农户,说明土地流转存在规模效应。土地流转对转出户的收入水平没有显著影响,可能的原因一方面由于土地流转市场发育不完善,没有显化租金;另一方面劳动力转移先于土地流转,使土地流转对农户家庭劳动力的释放作用不显著。(2)土地流转对农村内部收入差距的贡献度为4.19%,排名第五,表明土地流转不是造成农村内部收入差距拉大的主要原因。人力资本和村庄特征对农村内部收入差距影响较大。根据研究结论提出三点政策建议:第一,通过完善农地流转市场,稳定土地租金水平,使转出户获得合理的租金收入;第二,促进农地适度规模经营,提高转入户农业经营收入,缩小农户与非农经营户之间的收入差距;第三,提高农户就业竞争力,促进劳动力转移,增加转出户非农务工收入。     

农地整治对农户生计策略的影响分析——基于PSM-DID方法的实证研究

论文先对农户生计策略类型进行细分,利用倾向得分匹配-双重差分方法（Propensity Score Matching-Difference in Differences,PSM-DID）排除其他混杂因素,探讨农地整治在生计资本差异下对农户生计策略的影响效用,并运用多种匹配方法和反事实检验法对估计结果进行稳健性检验。结果表明：1）农地整治的实施能够显著改变二兼型农户的生计策略,但并不能显著改变专业型或多兼型农户的生计策略;2）农地整治对传统兼业型、现代兼业型、非农兼业型农户生计策略有显著影响,传统兼业型、现代兼业型农户比重显著增加,而非农兼业型农户比重显著减少,说明农户能够通过调整自身生计策略适应农地整治带来的变化,农地整治促进了农户生计多样化;3）通过多种匹配方法及反事实法开展稳健性检验,证实论文主要估计结果是稳健的。建议针对不同类型农户家庭需求制定差别化的鼓励政策;充分利用当地产业特色,依托农地整治与现代农业政策,带动现代兼业型农户发展区域特色农业或休闲农业。     

Process safety management lessons learned from a fire and explosion accident caused by a liquefied petroleum gas leak in an aromatics reforming unit in Taiwan

A severe fire and explosion accident was caused by a liquefied petroleum gas leak in Taiwan in 2019. This accident resulted in the loss of approximately US$3.5 billion in output value due to a one-and-a-half-year shutdown after the accident; however, no casualties were recorded at the accident scene. An analysis of the accident pipelines demonstrated that the pipeline leak had been caused by hydrochloric acid corrosion. Cause analysis based on the accident timeline, fault tree analysis, and causal factor charting indicated inadequacies in five elements of process safety management (PSM) namely mechanical integrity (MI), management of change, emergency planning and response, process hazard analysis (PHA), and process safety information (PSI) as the root causes of the accident. Furthermore, insufficient PSI (i.e., a lack of comprehensive understanding regarding corrosion mechanisms) was deemed to have been the core problem leading to the accident. This accident revealed common shortcomings that are often overlooked in PSM implementation in Taiwan; thus, the present research can serve as a vital reference for improving PSM programs in Taiwan.