Evaluating non-independent protection layers

The overall performance of a system that shares inputs and outputs between the BPCS and SIS can be better than the performance of a BPCS system and SIS system with dedicated inputs and outputs. Layer of Protection Analysis (LOPA) assumes that independent protection layers (IPLs) are independent of the initiating event (IE) components and any components of any other IPL in the LOPA scenario. This paper first focuses on those situations where protection layers all have separate components but are not independent solely because they:

• share common utilities such as plant air, electricity, or cooling water,
• share components in instrumented loops with other instrumented IPLs or the IE,
• be in the same location and share vulnerability to a common failure such as a fire, or extreme weather

Second, this paper demonstrates each of these situations using simple examples and a fault tree model of the LOPA scenarios to address the impact of sharing components or subsystems. Third, this paper, shows the difference between analyzing sharing at the order of magnitude LOPA level and using the best estimate component reliability data with fault tree models. Fourth, this paper provides examples showing the overall performance of a system that shares inputs and outputs between the IPLs or between the BPCS and SIS can be better than the performance of a BPCS system and SIS system with dedicated inputs and outputs. The maintenance and operational management issues involved with linking formerly “independent” systems can be managed to maintain the shared system performance advantage. Fifth, this paper suggests some general guidelines addressing sharing issues in LOPA. Finally, this paper discusses the potential benefits of selected sharing and the costs associated with assuring that the related complexities are controlled. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

Improved integration of LOPA with HAZOP analyses

Integrating Layer of Protection Analysis (LOPA) with Hazard and Operability Analysis (HAZOP) has many advantages over performing these studies separately. The merits include: fewer actions from the combined effort compared to performing only a HAZOP; team continuity resulting from the combined effort as opposed to two separate teams having possibly differing points of view; and, ultimately, a time and cost savings realized by the combination. This integration defines the risk associated with a given scenario, enabling better decisions that impact business assurance. By using the Center for Chemical Process Safety guidelines to define the independent protection layers upfront, the gray areas can often be reduced or eliminated; thereby enabling a more thorough LOPA. Examples include taking credit if a unit has two independent operators (outside and inside) responding to critical alarms, or taking credit for centralized control rooms that may allow immediate operator interaction and response. This article shows how the guidelines have been used successfully in joint HAZOP/LOPA studies, and describes an initial preparation protocol that can ensure high-quality results. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

LOPA as practiced at a global manufacturing API facility

The standard risk assessment practices used in industry since the OSHA 1910.119 regulation was issued, are to conduct Process Hazard Analyses (PHAs) for hazardous and exothermic (or otherwise high risk) processes. During PHAs, the potential consequences of an undesired event are evaluated along with the safeguards that exist to mitigate the consequences or reduce the frequency of the event. If the PHA team determines that the risk is still not tolerable, additional safeguards are recommended to reach a tolerable level of risk. Typically, a Quantitative Risk Assessment can be completed to evaluate the effectiveness of these existing or newly proposed safeguards. Unfortunately, this is a complex and time-consuming task. The relatively new methodology of Layer of Protection Analysis (LOPA) allows a PHA team to evaluate the effectiveness of safeguards in reducing risk in an efficient yet semiquantitative fashion using some basic assumptions and standard lookup tables. The LOPA methodology can be utilized to evaluate the effectiveness of Safety Instrumented Functions (SIF) (e.g., automated critical interlocks and alarms) to achieve a tolerable risk. The LOPA methodology provides consistency in an approach to risk assessments and communications. It can support an effective mechanical integrity or risk-based maintenance system for critical components of an SIF. This article describes LOPA and includes several scenarios that will provide an overview of how the LOPA methodology is used in a multibatch pharmaceutical facility. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

LOPA misapplied: Common errors can lead to incorrect conclusions

Layer of Protection Analysis is a powerful tool for quantitative risk assessments. If applied correctly, it can provide quick and efficient guidance on what additional safeguards are needed, if any, to protect against a given scenario. If misapplied, an overly conservative calculation of risk may result in over-instrumentation, additional life-cycle costs, and spurious trips. A nonconservative calculation of risk could result in an under-protected system and unacceptable risk of an undesired consequence occurring. This article describes several categories of common errors, some overly conservative and some nonconservative. Case studies of actual plant scenarios are used to illustrate. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009     

Improving process safety by addressing the human element

Celanese had several process safety incidents and near misses in 1996. Although there were several root causes, this article will address only one of them; human error. The system which was developed by Celanese to improve this human element is the conduct of operations system. The conduct of operations system has improved process safety performance of the human element by focusing on three operational areas: training, procedures, and general operations. Conduct of operations is a proactive approach to improve the current practices, improve the support systems and the behavior of the operator. The benefits include the following:

• Consistent application of training and procedures
• Reduction in human error, and
• Less process safety incidents

This article will describe the need for and the content of conduct of operations system as implemented by Celanese. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

Auditing process safety management in four levels

An audit must have a defined structure, an understood purpose, and enough details to assure completeness. It should be divided into discrete levels with specific topics so that the auditor can fully identify and understand the degree to which each facility or company complies with the requirements. Each of these levels should also be designed to analyze different types of information, implementation actions, and infrastructure. This article proposes and discusses a four-level approach to conduct a comprehensive and complete audit. The four levels are as follows:

• 1 Recognition and acknowledgment of the need to comply with a specific set of rules or regulations,
• 2 An implementation strategy and infrastructure,
• 3 Evidence of compliance, and
• 4 Quality assessments.

The content and purpose of each level as well as the interaction between levels is discussed and explained in this article. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

Guidance on developing safety performance indicators

This article summarizes a process for developing safety performance indicators. This is a topic of great importance for the measurement of the effectiveness of our PSM systems. The PSM is the OSHA regulation that covers companies in the United States that was issued in the year 1992. Since that time companies in the process industries have made great strides in implementing PSM systems. An important question is “How much progress have we made in actually reducing the number and severity of process events?” Other countries were also concerned about the effectiveness of their programs to address chemical accidents. In response to these concerns, the OECD published the documents described in this article. One of these documents sets out a safety performance indicator process that allows a company to:

• assess whether it is implementing appropriate chemical safety programs and policies,
• evaluate whether these programs and policies are achieving their desired objectives, and
• help determine the extent to which such programs and policies are making a difference.

This will allow a company to identify whether there is appropriate emphasis on different aspects of safety management and provide insights needed for setting priorities for future investment of resources. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009     

X-Teams: How To Build Teams That Lead, Innovate, and Succeed by Deborah Ancona and Henrik Bresman

I am retiring from the profession and from this position as your book review editor; the very capable Donovan Hardenbrook will be your next editor. I think we have worked out a seamless transition, but Donovan will doubtless bring his energy and innovation to the position. These nearly five years as editor have been a lot of work but a great deal of satisfaction too. This position is the best one in the world for keeping on top of the newest thinking in product development, for being able to see the latest books as—or even before—they are published, and for learning by editing the work of knowledgeable reviewers critically. Some statistics: In nearly five years, we received 560 books for review, reviewed 144 of them, processed 659 review drafts, and discarded about 430 books (mostly to The Prisoners Literature Project). A more modern metric: I received 3,372 e‐mails about book reviews (and probably sent a similar number). Of course, I've had much help, which I would like to acknowledge. Tony Di Benedetto, the journal editor, was a constant source of encouragement and support, and Beebe Nelson, the former book review editor, backed me up. Our 41 active reviewers did the real work, and some of them are prolific reviewers: Mark Hart, George Castellion, Ruediger Klein, and Gerald Mulenburg each reviewed 10 or more books. Kristi Bennett, our copyeditor, has done a wonderful job of ensuring the consistency of these offerings. Finally, we are indebted to about 70 book publishers (technically, imprints) that supplied the review copies gratis. Books reviewed in this issue:

• ? X‐Teams: How To Build Teams That Lead, Innovate, and Succeed
• ? Edison on Innovation: 102 Lessons in Creativity for Business and Beyond
• ? Something Really New: Three Simple Steps to Creating Truly Innovative Products
• ? Smart Isn't Enough: Lessons from a Work Performance Coach
• ? The Power of Mobility: How Your Business Can Compete and Win in the Next Technology Revolution

     

Integration of safety management effectiveness into QRA calculations

Quantitative Risk Analysis (QRA) has become an often used method in the process industry for improving safety and for land-use planning. In computing the risk by this methodology the frequency of an accident is often assessed by using generic failure frequencies which are based on historical data of incidents from databases. Little or no adjustment is made for the effectiveness of the safety management of the industrial site. Since most incidents are caused by management problems, QRA has to take into account the local safety management system. Otherwise, the results of QRA will not provide reliable information of the hazards and the corresponding risk from installations. Therefore, today's understanding of safe industrial operations requires an integrated risk assessment under the consideration of technical, organizational, and managerial aspects. This article describes a method which allows assessing the effectiveness of the local safety management system and its integration into the QRA using a single management factor. This method was developed with the aim of providing a tool which would allocate a quantitative measure for the effectiveness of the local Safety Management System for the purpose of using it directly in the QRA. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

PSM system upgrade in response to an Occupational Safety and Health Administration NEP inspection

This article presents a brief analysis of the Occupational Safety and Health Administration (OSHA) Petroleum Refinery Process Safety Management National Emphasis Program (NEP) citation results as of early 2009. It includes trends distilled from the OSHA inspections performed to date. Recommendations for preparing for PSM NEP level inspections are provided. A proven approach to designing and implementing an upgrade project for OSHA process safety management systems and EPA risk management program is described. The model presented can be targeted to a facility's NEP specific citations or used for a general PSM system effectiveness upgrade. This article includes recommendations for improving PSM as a result of an NEP inspection. The recommendations are for the PSM elements that routinely have major OSHA citations; that is: Operating Procedures, Mechanical Integrity, Process Hazards Analysis, Process Safety Information, Management of Change, and Incident Investigations. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009     

THE ENGINEERING ECONOMIST: AIMS AND SCOPE OF FOCUSED AREAS

The Engineering Economist is a refereed journal published jointly by the Engineering Economy Division of the American Society of Engineering Education (ASEE) and the Institute of Industrial Engineers (IIE). The journal publishes articles, case studies, surveys, book and software reviews, and readers' comments that represent current research, practice, and teaching involving problems of capital investment.

The journal seeks submissions in a number of areas, including, but not limited to, capital investment analysis, cost estimation and accounting, cost of capital, design economics, economic decision analysis, education, policy analysis (i.e., governmental), and research and development.

As noted in the editorial, we are celebrating the 50th volume of our journal and we are taking this opportunity to reinvigorate our purpose. This is to be facilitated with the designation of area editors assigned to specific submission focus areas. These areas are clearly defined below and the representative area editors are introduced. Their contact information is provided in case prospective authors have questions about potential submissions in prospective areas. However, all submissions should be sent to the editor-in-chief. The focus areas are listed alphabetically, followed by case study and book/software review submission guidelines. Following the definition of the areas are the new electronic submission guidelines for the journal.     

Improvements in the safety screening of resin manufacturing processes

Consequences of acrylic resin reactor runaways can be devastating, as it is evident in investigation reports of industrial accidents. Critical in preventing major accidents is the safety screening of any acrylic resin formula to be manufactured in large scale. Computer model simulations facilitate the evaluation of “layers of protection” against acrylic polymerization runaways. This work describes the adaptation of a chemical process dynamic simulator (DuPont™ TMODS™) for use in simulating acrylic polymerization runaways. “Loss of cooling” and “monomer pooling (accumulation)” scenarios are the causes of these runaways. Simulations show that scenarios leading to “monomer pooling” result in more energetic runaways and to larger emergency relief capacity requirements than “loss of cooling” scenarios. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

Vergleichende Analyse der technisch-wirtschaftlichen Bedingungen von PV-Anlagen Mit Süd- und Ost-West-Ausrichtung

PV power plants with east-west-orientation have a lower energy production per installed kW_p due to their orientation than those facing to south. Thus they need a reduction of costs to compensate the lack of energy production and to have the same cost effectiveness as PV plants with south-orientation. This paper tries to show, how and if PV plants with east-west-orientation can be more profitable than PV plants with south-orientation. Therefore, the energy production was simulated for PV plants with an orientation to east-west and to south with different inclinations in a place with high irradiation (Freiburg) and a place with low irradiation (Hamburg). A calculation of profitability was made for each PV plant including energy production as well as ascertained costs. This are the main outcomes:

The profitability of PV plants with east-west-orientation is not better than the profitability of PV plants with south-orientation.

The profitability of PV plants with east-west-orientation is better than the one of PV plants with south-orientation when the costs of mounting systems are much lower for east-west mounting-systems than for mounting-systems with south-orientation and the costs of grid-connection and rent are high too.

The profitability of PV plants with east-west-orientation is higher in regions with low irradiation.

     

Evaluating the efficiency and productivity change within government subsidy recipients of a national technology innovation research and development program

This study analyzes the efficiency and productivity change within government subsidy recipients of a national technology innovation research and development (R&D) program. We examine 6,990 government‐sponsored, completed R&D projects during the last three performance follow‐up survey years from 2010 to 2012, and present a design of the sample of panel data to cope with the typical R&D performance time lag using a set of massive observations associated with completed R&D projects for the past 7 years from 2005 to 2011. In particular, data envelopment analysis is adopted to measure the efficiency and productivity change, which is measured in the Malmquist index. Parametric and nonparametric statistical tests are carried out to check for statistically significant differences among the characteristics regarding the types of government subsidy recipients. This study's major findings are as follows. First, during the entire period analyzed (2010–2012), there was a similar yearly pattern of statistically significant differences in the government subsidy means among the recipient types. In contrast, there were no obviously equivalent differences in the efficiency and productivity change. Second, the productivity had increased year on year, but the increments were reduced from year to year. Third, the productivity change was induced mainly by the Frontier‐shift, which indicates overall technology innovation progress, compared with the Catch‐up, which only indicates a simple increase in the efficiency. In particular, in this empirical analysis, the recipient types of ‘national laboratory’ and ‘large company’ had relatively larger sizes of government subsidies per project. However, the efficiency and productivity change of these types was not better than the others. This implies, therefore, that the government should control the ratio of the subsidy to the total R&D budget with an appropriate upper limit.

• I empirically evaluate the productivity change within a national technology innovation R&D program.
• I design a sample of panel data to cope with the typical R&D performance time lag using massive observations.
• There is no obvious relationship between the government subsidy size and R&D productivity change.
• Some particular types of government subsidy recipient are inferior in terms of R&D productivity change.
• It practically implies that the government should control the ratio of the subsidy to the total R&D budget.

     

The use of the Pareto shape parameter as a leading indicator of process safety performance

Metrics addressing process safety incident performance typically focus on frequency and severity statistics. Often, these lagging metrics are not overly sensitive to actual performance, making trending and forecasting difficult. This article presents the results from a statistical study of a large incident dataset where changes in the Pareto shape parameter were observed as a function of time. This approach has been found to give far better insight into process safety performance than traditional incident metrics and readily relates back to concepts such as the “incident triangle” and “layers of protection.” Through the application of this approach, trends within process safety incident performance have been observed earlier, and more accurate forecasting has allowed for the identification of anomalies. In turn, these critical observations have allowed for the better structuring and targeting of process safety programs. Although incident data are generally considered as a lagging indicator, this approach has clearly reduced the lag time associated with this type of data and has given valuable insight into the current status of process safety performance. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009     

Book Reviews

The first review describes the eighth book we have reviewed on the general topic of faster new product development. This book is distinguished by its emphasis on human issues, especially in the context of contracted development for an original equipment manufacturer. The second review covers a book that contrasts the Japanese and U.S. approach to product development. The book indicates that U.S. companies should put more emphasis on early predevelopment activities. The third review describes how Kodak's black and white film-making operation was overhauled by a team effort. Our reviewer suggests that many of the book's team-building lessons must be adopted for any company to change its culture and improve its product development performance. The fourth review describes a short book about quality function deployment (QFD). Although the book lacks specific product development examples, the reviewer recommends it as a helpful primer on this important product development tool. The fifth review reports on a technology management book. The book comprises a series of separately authored chapters on varied issues, some of which are directly pertinent to developers of technology-based new products. The reviews conclude with a brief note about a book on rapid prototyping.     

Cheddar or Swiss? How strong are your barriers?

This article describes a company's experience with process safety metrics and describes systematic methods to improve safety performance. As a result of a major accident, an internal investigation identified that although a site may have numerous measures for tracking operational and safety performance, these measures may not focus on leading indicators that could provide early warning of potential major incidents. To systematically reduce incidents, especially, low probability high consequence process safety events, it is necessary to focus on prevention and specifically the strength of the barriers. The approach described in this article, therefore, aims to create a combination of Process Safety Performance Indicators that lead to stronger more robust barriers. While industrial history tells us that such high consequence events are infrequent, this significant process safety risk is always present in production operations, and thus needs to be continuously assessed and reduced through systematic safety management. Within one company, this recognition has resulted in a substantial strengthening of process safety risk management through a more comprehensive system of controls embedded within its new Operating Management System, which is being implemented at the site level across all of its operations globally. This article explores the ongoing methodology and approach being used to select a limited but crucial set of Process Safety Performance Indicators to enable effective measurement and the appropriate management of process safety performance. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009     

Build an Industry Hot Rod: The Nuts and Bolts of Leaving Competitors in the Dust by Marvin L. Patterson

Books reviewed in this issue:

• ? Build an Industry Hot Rod: The Nuts and Bolts of Leaving Competitors in the Dust
• ? Innovating at the Top: How Global CEOs Drive Innovation for Growth and Profit
• ? Determinants of Innovative Behaviour: A Firm's Internal Practices and Its External Environment

     

The important role of pressure in supercritical fluid process development revealed by reaction calorimetry

The technique of reaction calorimetry adapted for use with reactions in supercritical fluids was used to study some safety aspects of the free-radical dispersion polymerization of methyl methacrylate in scCO₂. The reaction heat rate profile was found to change very little once the dispersion was well formed. Furthermore, it provided valuable information for the calculation of the maximum temperature attainable by the synthesis reaction (MTSR) in the case of a hypothetical cooling system failure. Finally, a series of failure scenarios demonstrated the importance of the pressure as far as the safety of the process is concerned, due to the particularity of the supercritical state of the solvent. It was found that the acceleration phase of the reaction is the most critical period, since a cooling system failure during this phase leaves very little time before the pressure overcomes the operational limit of the equipment and results in an accident. Hence, the utility and the importance of defining the reaction heat rate profile become obvious and several safety features have to be taken into consideration when designing a SCF process. © 2009 American Institute of Chemical Engineers Process Saf Prog 2009     

Interaction of acoustic waves with flame front propagation

The mechanisms of laminar premixed flame propagation have been intensively studied over the last century. Numerous authors have highlighted intrinsic phenomena in flame propagation such as Darrieus-Landau instability and Rayleigh-Taylor instability. Rayleigh-Taylor instability is often linked to the interaction between the flame front and an acoustic wave. To better characterize the interaction between a flame and aerodynamic conditions, we designed a special vertical closed tube apparatus. Our analysis focused on the behavior of a flame that propagates in a uniform stoichiometric mixture of H₂ and O₂ diluted with nitrogen. The experimental investigation revealed that acoustic waves emitted as the flame formed near the ignition point could increase the flame front surface by a factor of 10. An acoustic node with an amplitude of 1.3 m was identified and seemed to be responsible for the disappearance of one of the acoustic modes and for a reduction in the average flame surface. This could explain why the flame trajectory had two distinct parts: one corresponding to propagation at a high speed in the lower part of the tube, and the other with a slower speed in the upper part of the tube. The flame surface seemed to depend primarily on the frequencies of vibration and marginally on the nature of the reactive components. Propagation velocities, obtained by multiplying these flame surfaces by the fundamental burning velocity, strongly depended on the mixture reactivity. © 2009 American Institute of Chemical Engineers Process Saf Prog, 2009