Public perceptions of design options for new nuclear plants in the UK

An important consideration for any new nuclear build programme is an understanding of the public's viewpoint, as in many countries this can influence the direction of future energy markets. This paper presents a first attempt at understanding public views on the design of new nuclear plants. A survey of 1304 adults in the UK was carried out using a questionnaire developed in this research. The study suggests that the general public are willing and able to express preferences for design aspects of nuclear power plants and that meaningful information can be obtained to inform designers. Responses indicate that public preferences are consistent with current design practice for nuclear power plants. Further analysis reveals that public preferences related to plant design are not influenced strongly by their existing attitudes. Our findings contribute to the literature on the governance of energy supply technologies and the involvement of the public in the innovation process. We argue that involving the public in the design of nuclear power plants is an important aspect of a more transparent, participatory approach intended to improve trust in the governance of future energy supply options.     

A new approach on troubleshooting of cathodic protection: A case study

The aim of this paper is to suggest an effective procedure to eliminate a major deficiency in impressed current cathodic protection (CP). Current work describes performed activities through jetty cathodic protection troubleshooting as a case study. Although CP troubleshooting is straightforward, sometimes it is very complicated and confusing. To eliminate the appeared imperfection, different procedures were carried out; the root cause of the trouble in the system was shown to be in reversed current. Here the current which passed throughout installed junction were measured to survey reversed current. Current work offers a new approach in CP troubleshooting.     

基于屏障理论的安全事故原因分析方法研究

本文系统介绍了基于屏障理论的事故原因分析方法,编制事件时间链图,完整还原事故发生经过,并通过屏障辨识及分析,确定事故的直接原因、间接原因和根本原因,为事故原因分析提供参考方法和工具。最后通过实际案例进行了应用和验证。     

Requirements for improved process hazard analysis (PHA) methods

In order to develop better process hazard analysis (PHA) approaches, weaknesses in current approaches first must be identified and understood. Criteria can then be developed that new and improved approaches must meet. Current PHA methods share common weaknesses such as their inability specifically to address multiple failures, their identification of worst-consequence rather than worst-risk scenarios, and their focus on individual parts of a process. There has been no comprehensive analysis of these systemic weaknesses in the literature. Weaknesses are identified and described in this paper to assist in the development of improved approaches. Knowledge of the weaknesses also allows PHA teams to compensate for them to the extent possible when performing studies.Key criteria to guide the development of improved methods are proposed and discussed. These criteria include a structure that facilitates meaningful brainstorming of scenarios, ease of understanding and application of the method by participants, ability to identify scenarios efficiently, completeness of scenario identification, exclusion of extraneous scenarios, ease of updating and revalidating studies, and ease of meeting regulatory requirements. Some proposals are made for moving forward with the development of improved methods including the semi-automation of studies and improvements in the training of team members.     

Ranking of process safety cultures for risk-based inspections using indicative safety culture assessments

Although major hazard industries have no legal obligations to demonstrate a good safety culture, it is an increasingly important factor for risk-based inspections. This paper describes the development and evaluation of a relatively simple method for external indicative assessment of the process safety culture in major hazard industries. As a first step, a tool was developed. Second, the tool was successfully tested in a workshop with major hazard inspectors. After this ‘proof of concept’ and a few adaptations to improve the tool, quantitative evaluation and validation were carried out with a representative sample of major hazard inspectors in the Netherlands. In this stage, the tool comprised 30 questions, of which 19 sufficiently frequent valid responses were given for the validity test. The evaluations demonstrate that without specific preparations, inspection teams can use the tool to discriminate between plants with poor or good safety cultures. That is sufficient for ranking as additional input for risk-based inspection strategies. The resulting indicative ‘scores’ for safety culture correlate meaningfully with the quality of process safety management systems and the number of (legal) non-compliances, which were identified by the inspection team at the same occasion. The use of the tool can be further improved by training inspectors, making minor adaptations of the inspection process, and broadening the scope of a few questions. It is expected that external assessments of safety culture will become increasingly important not only for inspectorates, but also for a range of other external stakeholders.     

Determining a realistic ranking of the most dangerous process equipment of the ammonia production process: A practical approach

OCI Nitrogen seeks to gain knowledge of (leading) indicators regarding the process safety performance of their ammonia production process. The current research determines the most dangerous process equipment by calculating their effects resulting from a loss of containment using DNV GL's Phast™ dispersion model. In this paper, flammable and toxic effects from a release from the main equipment of an ammonia plant have been calculated. Such an encompassing approach, which can be carried out for an entire plant, is innovative and has never been conducted before. By using this model, it has been demonstrated that the effects arising from an event of failure are the largest in process equipment containing pressurized synthesis gas and ‘warm’ liquid ammonia, meaning the ammonia buffer tanks, ammonia product pumps, and the ammonia separator. Most importantly, this document substantiates that it is possible to rank the most hazardous process equipment of the ammonia production process based on an adverse impact on humans using the calculated effect distance as a starting point for a chance of death of at least 95%. The results from the effect calculations can be used for risk mapping of an entire chemical plant or be employed and applied in a layer of protection analysis (LOPA) to establish risk mitigation measures.     

Falls from height during the floor slab formwork of buildings: Current situation in Spain

Problem

One of the phases with the highest risk of falls from a height in the construction of a building is during the floor slab formwork stage. This paper analyzes this particular risk, as well as the most frequently used fall-protection systems.

Method

A survey was carried out to define the current situation in Spain with regard to falls from a height during floor slab formwork and the fall-protection systems used to prevent such a risk.

Results

The results of the survey clarified the current situation in Spain with regard to this risk, and made it clear that there is considerable risk of falling from a height during the floor slab formwork stage.

Discussion

All the safety systems analyzed presented a series of weak points that should be studied in detail before they can be used on building sites.

Impact on industry

The risk of falling associated with floor slab formwork and the most frequently used protection systems are analyzed. As no research had been carried out to date on this type of risk, we consider the research presented in this article to be a pioneer in the field.     

结构防火在舰船防火设计中的应用

从舰船火灾发生的规律和特点出发,本着“重点在于防”的精神,论述了舰船消防设计的原则和任务,以及舰船结构防火中必须考虑的几个问题。     

Method for identifying errors in chemical process development and design base on accidents knowledge

It has been claimed that the high accident rate in the chemical process industry is due to poor dissemination of accident knowledge that affects directly the level of learning from accidents. In response to this situation, this paper utilized past accident knowledge as a basis to develop a safety oriented design tool whereby the accident information were directly disseminated into plant design. The method was developed based on our previous accident analysis of design error in which the common design errors were ranked in accordance to their frequency and its origins during normal plant design project. Based on the design error ranking and its origin at a specific design phases, a method for design error detection is proposed. The method is expected to be able to identify the possible design error and its causes throughout chemical process development and design. The main objective is to trigger safe design thinking at the specific design phases so that appropriate action for risk reduction could be timely implemented. The Bhopal and BP Texas tragedies are used as case studies to test and verify the method. The proposed method can detect up to 74% of design errors.     

Inherently safer design review and their timing during chemical process development and design

This paper discusses the enhancement of inherent safety review and its implementation in the chemical process development and design. The aim is to update and improve the existing inherently safer design review (ISDR) practices during design of chemical process plant by exploiting major accident cases from the U.S. Chemical Safety Board (CSB) and Failure Knowledge Database (FKD). Although the basic guidelines to conduct ISDR during design phase are available, however they are too general and incomplete. The review criteria and their best timing for application are still missing. This paper attempts to develop the accident-based ISDR for chemical process plant design. The proposed accident-based ISDR is supported with detail review criteria for each phase of process design. The timing of ISDR application is corresponding to the common design tasks and decisions made in the design project. Therefore, timely design review could be done at the specific design task and the findings help designer to make a correct decision making.     

Smoke control of a fire in a tunnel with vertical shaft

The aim of this research is to find the optimum smoke extraction rate through the ventilation shaft in case of a fire in a long road tunnel. Furthermore, it is also investigated whether the current emergency ventilation design practice using a vertical shaft can limit the smoke propagation from a fully loaded gasoline tank lorry fire. For this research, scaled model experiments were carried out using a 20 m- long model tunnel with a vertical shaft. A CFD modeling tool was also extensively utilized to investigate the extremely dangerous situation in which a fully loaded gasoline tank lorry is burning inside a long road tunnel.     

Measuring safety culture in a research and development centre: A comparison of two methods in the Air Traffic Management domain

This paper describes two safety surveys carried out in an Air Traffic Management Research and Development centre (EUROCONTROL Experimental Centre). The paper discusses the differences and similarities between the two tools with regard to their development, the method of conducting the surveys, the results and their implications. It has been estimated that about 50%¹ to 60%² of accidents and incidents appear to have their roots in the design and development process, and since this is the core business of the EEC, it was deemed necessary to investigate the maturity of safety at the EEC. The challenge for the EUROCONTROL Experimental Centre (EEC) was to develop a tool that is relevant to a research and development environment with the objectives of (i) identifying areas of weakness in the safety culture of the organization (ii) helping in developing a Safety Management System. The first objective was addressed by developing a Safety Culture Survey (SCS) tool and surveying the EEC (March, 2003). The second objective was addressed by customizing an existing (SMS) survey tool (RD) for the R&D environment. The SCS is based on traditional measures adapted to ATM and then to R&D, and the River Diagram (RD) is more of a safety management survey, adapted from other industries and already applied to HQ (EUROCONTROL Head Quarters) to examine their commitment to safety. Nevertheless, the two surveys have been compared to see where they agree and where they ‘dissociate’. Overall, the SCS has a broader focus on “softer issues”, i.e. more complex issues of ‘trust in management’. Diagnostically, the River Diagram survey helps the practitioner develop SMS implementation plans more readily than the Safety Culture survey.     

The feasibility of encouraging inherently safer production in industrial firms

Inherent Safety is generally recognised as an important concept in the design of chemical plants. It is, however, often regarded as the sole province of engineers. Inspired by the successful development in the last decade from cleaner technology towards Cleaner Production, we explored in this research the feasibility of what we call Inherently Safer Production. Four pilot cases were carried out, two in the Netherlands and two in Greece; three in existing plants, one at the design stage. A methodology to generate inherently safer technological options was developed and tested. In all four cases, a number of options for inherently safer production were identified, while more traditional safety options were also identified. The great majority of options was shown to have pay back times of less than 2 years. Overall, 25% of the options were implemented during the project.In existing plants, the option generation process can be organised as a collective learning and inspiring effort. This can be of considerable value on its own, apart from the implementation of the (technological) options identified. We conclude that Inherently Safer Production is a feasible concept, that it has great potential for simultaneous improvement of safety and economic performance, and that it deserves to be further developed.     

基层安全生产监管体制研究——关于安全生产法律制度实施与完善的研究(一)

基于现行基层安全生产监管体制有许多不适应安全生产工作的问题,提出扩大基层安监体制新方案,目的在于解决基层安监体制中存在的种种问题。该方案的核心是建立县区安监局直属的安全工程监测站,取代现有的乡镇街道安监站。定性为事业机构和技术服务机构,建立一支安全技术专业人员队伍,以加强其力量,开展所有的安全工程监测等技术服务工作。为配合该项工作推进,应推行注册安全工程师资格考试,以加强基层安监体制内人才队伍建设。     

大型体育馆消防性能化设计中安全疏散时间的分析和研究

《体育建筑设计规范》对体育馆安全疏散时间有明确的要求,对于二级耐火等级的体育馆控制疏散时间定为3min～4min。以此作为某大型体育馆消防性能化设计中安全疏散时间依据,运用人员疏散模拟软件分别对体育馆安全疏散时间进行的分析和比较,探讨了具体案例中如何确定和评估消防性能化设计的安全水平,即消防性能化设计安全水平不应低于处方式安全水平的设计理念。研究结果表明,现行设计宽度可满足疏散要求,充分保证人员的安全疏散。     

Studying organisational cultures and their effects on safety

How do organisational cultures influence safety? To answer this question requires a strategy for investigating organisational culture. By far the most widely used research strategy is the perception survey. An alternative is for researchers is to immerse themselves in one or more organisations, making detailed observations about activities and drawing inferences about the nature of the organisation’s culture (the ethnographic method). A third technique makes use of the wealth of material that is assembled by inquiries into major accidents. This paper describes how this material can be used to provide insights into organisational cultures. It draws on specific examples from the author’s own work as well as the cultural analysis carried out by the Columbia Accident Investigation Board. It concludes with some additional suggestions for carrying out research on safety-relevant aspects of organisational culture.     

基于指标体系的城市区域火灾风险评价系统开发

本文阐述了基于指标体系的城市区域火灾风险评价软件设计思想与开发。首先,针对我国城市和经济的特点,消防的现状和发展规律,在广泛收集和分析国内外资料的基础上,通过火灾统计资料分析、实地调研、Delphi等方法,以居住区为例建立了相应的火灾风险评价指标体系,采用层次分析法计算各指标的权重;其次,根据城市的复杂性和多样性以及由此造成的不同城市、不同区域的火灾风险评价指标体系方面的差异,采用面向评价研究者与操作者的软件设计思想,利用指标体系的构建方法作为软件功能流程的设计依据,设计并开发了《城市区域火灾风险评价系统》。该软件不仅能应用于评价实践,而且能为评价理论研究提供有力的支持。     

Inherent risk assessment methodology in preliminary design stage: A case study for toxic release

At preliminary design stage, process designers normally lack of information on the risk level from process plant. An inherently safer process plant could be designed if the information of risk levels could be known earlier at the preliminary design stage. If the risk level could be determined, there is a possibility to eliminate or reduce the risk by applying the well-known concept: inherent safety principle. This paper presents a technique to determine the risk levels at preliminary process design stage using a 2-region risk matrix concept. A model to calculate the severity and likelihood of a toxic release accident was developed in Microsoft Excel spreadsheet. This model is integrated with process design simulator, iCON to allow for data transfer during preliminary design stage. 2-region risk matrix is proposed and used to evaluate the acceptability of the inherent risk based on the severity and likelihood rating. If the inherent risk level is unacceptable, modification for improvement can be done using the inherent safety principles. A case study has been carried out to illustrate the benefit of applying this newly developed technique. It was successfully shown that an inherently safer plant could easily be designed by applying this technique.     

A violent,episodic vapour cloud explosion assessment: Deflagration-to-detonation transition

A large vapour cloud explosion (VCE) followed by a fire is one of the most dangerous and high consequence events that can occur in petrochemical facilities. The current process of safety practice in the industry in VCE assessment is to assume that all VCEs are deflagration. This assumption has been considered for nearly three decades. In recent years, major fire and VCE incidents in fuel storage depots gained considerable attention in extreme high explosion overpressure due to the transition from Deflagration to Detonation (DDT). Though the possibility of DDTs is lower than deflagrations, they have been identified in some of the most recent large-scale VCE incidents, including Buncefield (UK), 2005, San Juan explosion (US), 2009, and IOCL Jaipur (India), 2009 event. Such an incident established the need to understand not only VCE but also the importance of avoiding the escalation of minor incidents into much more devastating consequences.Despite decades of research, understanding of the fundamental physical mechanisms and governing factors of deflagration-to detonation transition (DDT) transition remains mostly elusive. An extreme multi-scale, multi-physics nature of this process uncertainly makes DDT one of the “Grand Challenge” problems of typical physics, and any significant developments toward its assured insistence would require revolutionary step forward in experiments, theory, and numerical modelling. Under certain circumstances, nevertheless, it is possible for DDT to occur, and this can be followed by a propagating detonation that quickly consumes the remaining detonable cloud. In a detonable cloud, a detonation creates the worst accident that can happen. Because detonation overpressures are much higher than those in a deflagration and continue through the entire detonable cloud, the damage from a DDT event is more severe. The consideration of detonation in hazard and risk assessment would identify new escalation potentials and recognize critical buildings impacted. This knowledge will allow more effective management of this hazard.The main conclusion from this paper is that detonations did occur in Jaipur accident at least part of the VCE accidents. The vapour cloud explosion could not have been caused by a deflagration alone, given the widespread occurrence of high overpressures and directional indicators in open uncongested areas containing the cloud. Additionally, the major incident has left many safety issues behind, which must be repeatedly addressed. It reveals that adequate safety measures were either underestimated or not accounted for seriously. This article highlights the aftermath of the IOCL Jaipur incident and addresses challenges put forward by it.