Chapter 2 - Hazan (Quantified risk assessment)

Background: Fire safety is one of the most important issues in high-rise buildings. The purpose of this study is to assess maximum possible loss in the fire in Central Insurance Building of Islamic Republic of Iran using the layer of protection analysis (LOPA) method.
 Method: In 2017, this analytical study was conducted on the 21-floor building of the Central Insurance in Iran. To identify the hazard sources and assess the maximum possible loss, the authors used the preliminary hazard list (PHL) and layer of protection analysis (LOPA) respectively. In addition, the analysis of the study data was performed based on the 10×10 risk assessment matrix.
 Results: The results of the PHL showed that 26 hazardous conditions and four major sources including structural engineering, fire alarm systems and fire extinguishers, design and maintenance of building safety, and behavioral habits were identified as main hazards of fire in the studied building. The application of the LOPA method showed that highest risk level was associated with the fire caused by the exhaust heat from the engine room (RL=48) and the emergency power generator diesel (RL=40), respectively.
 Conclusion: The findings of this study indicated that calculating the maximum possible loss in the fire of high-rise buildings can help to increase the safety factor. Moreover, the use of the two methods, PHL and LOPA, can be useful in these types of risk assessments.

Preface.- Acknowledgements.- Part 1. Environmental Security.- Environmental Security, Critical Infrastructure and Risk Assessment: Defmitions and Current Trends D.A. Belluck, R. Hull, S.L. Benjamin, I Alcorn, I. Linkov.- Security and the Environment in the Middle-East Water Issues B. Morel.- Potential of Solar Thermal Desalination to Defuse Water as a Conflict Issue in the Middle East - Proposal for Functional Cooperation in the Gulf of Aqaba H. G. Brauch.- Water Resources Management and Environmental Security in MediterraneanTransboundary River Basins I. Ganoulis .- The Role of Comparative Risk Assessment in Decision Analysis. Marshlands of Mesopotamia and Affected Riparian Countries C. Maxwell .- A Future for the Dead Sea Basin: Options for a More Sustainable Water Management C. Lipchin .- Are Standard Risk Acceptability Criteria Applicable to Critical Infrastructure Based on Environmental Security Needs? D.A. Belluck et al.- From global warming to water scarcity: what are the most urgent environmental problems of the region. Report of the discussion Group on Environmental Security A. Morel, B. Morel .- Part 2. Environmental Management.- The Interconnection Between the Built Environment, Ecology and Health H. S. Koren, C. D. Butler.- Statistical Models for Distributions of Ambient Fine Particulate Matter S. Yeh, M J. Small.- QnD: A Scenario-Based Gaming System for Modeling Environmental Processes and Management Decisions G. A. Kiker et al.- Mapping of Relative Risk U. Schlink et al. Understanding Risk Culture and Developing a 'Soft' Approach to Risk Assessment Methodologies S. Rao .- Different Preventive Strategies Require Diversified Risk Assessment Models S. Menoni.- Coupling Public Participation and Expert Judgment for Assessment of Innovative Contaminated Sediment Technologies T. P. Seager et al. Environmental Risk Assessment and Management: Promoting Security in the Middle East and in the Mediterranean Region.Report o fthe Working Group on Environmental Risk Assessment and Management J. Ganoulis, L. Simpson .- Part 3. Case Studies in Environmental Security and Environmental Management.- Reuse of Wastewater in Agriculture- Economic Assessment of Treatment and Supply Alternatives as Affecting Aquifer Pollution N. Haruvy.- Minimizing the Risks Associated with Water Scarcity S. Arlosoroff.- Integrated Risk-Based Management of Water Resources in the Jordan River Basin E. Levner.- Outcome of Nato Workshop on Radiological Risk in Central Asia M.K.. Zaidi et al.- Public Transport Policy & Measures That Could Improve the Air Quality in Major Cities in Syria, A Case Study: Damascus J. Chahoud .- The Modeling of Combine Impact of Waste Heat Discharge into Offshore Strip from Cooling Systems and Power Plants A. Andrijievskij et al.- Role of Synergy in Biological Risk Assessment N. Goncharova.- Cooperative Networks for Environmental Risk Analysis Studies: The Case of the Middle East Region M.K. Zaidi, I. Ganoulis.- List of Participants.- Author Index .-

Risk acceptance and tolerability criteria are tools that are used to evaluate and control risks. Although such criteria have been used for many years in different sectors of applications, their rationale and use are still being discussed. Three issues commonly addressed are: 1 the type and form of the criteria (e.g., general formulations compared to tailor-made criteria for specific applications) 2 the criteria’s relationship with value generation 3 methods for and uncertainties in the risk assessments that are used to verify that the criteria are met. In this paper, we take a closer look at these issues. The aim of the paper is to stimulate the ongoing debate about the applications of risk criteria. A number of propositions is presented that are based on three case-studies: the use of acceptance and tolerability criteria in the Dutch flood safety policy, the Dutch major hazards policy, and the Norwegian petroleum industry.

ExSys-LOPA for the chemical process industry

For the purpose of solving problems in water treatment system of the power station boiler from perspective of chemical process safety, a new method which uses the LOPA method in risk assessment for anticorrosion and scale inhibition properties of boiler system is proposed. First of all, a new annotation on the basic principle and calculation steps of LOPA is made in this paper. And then the consequence of the hazard scenario is determined by calculating the probability of accidents, such as putting poor quality water treated by the water treatment agents as initial event. Finally, specific implementable recommendations are provided by comparing the risk levels of independent protective layers system and ordinary system. The results show that the method that LOPA used in risk assessment for anticorrosion and scale inhibition properties of boiler is feasible, measures that recommended can reduce the risk; LOPA can further enrich HAZOP analysis results when introduced into boiler capacity link; layers of protection analysis, risk assessment together with humanistic management could be a new and effective security management model used by energy enterprise.

The commercialization of eco-friendly hydrogen vehicles has elicited attempts to expand hydrogen refueling stations in urban areas; however, safety measures to reduce the risk of jet fires have not been established. The RISKCURVES software was used to evaluate the individual and societal risks of hydrogen refueling stations in urban areas, and the F–N (Frequency–Number of fatalities) curve was used to compare whether the safety measures satisfied international standards. From the results of the analysis, it was found that there is a risk of explosion in the expansion of hydrogen refueling stations in urban areas, and safety measures should be considered. To lower the risk of hydrogen refueling stations, this study applied the passive and active independent protection layers (IPLs) of LOPA (Layer of Protection Analysis) and confirmed that these measures significantly reduced societal risk as well as individual risk and met international standards. In particular, such measures could effectively reduce the impact of jet fire in dispensers and tube trailers that had a high risk. Measures employing both IPL types were efficient in meeting international standard criteria; however, passive IPLs were found to have a greater risk reduction effect than active IPLs. The combination of RISKCURVES and LOPA is an appropriate risk assessment method that can reduce work time and mitigate risks through protective measures compared to existing risk assessment methods. This method can be applied to risk assessment and risk mitigation not only for hydrogen facilities, but also for hazardous materials with high fire or explosion risk.

This paper discusses the use of risk assessment (RA) for analyzing the environmental suitability of natural gas pipelines and highlights RA's linkages with environmental impact assessment. The paper contends that RA is an essential tool when assessing the suitability of gas pipelines, and that risks associated with such proposed activities should be used as fundamental criteria to determine route selection. By doing so, fatality risks related to pipeline failures can be reduced. The paper also contends that the risk acceptance criteria adopted by the State of Sao Paulo are overly permissive when compared to other criteria used around the world. Therefore, the State should consider revising and strengthening its risk acceptance criteria to be up-to-date with international standards.

Off-site hydrogen refueling stations (HRS) handle large volumes of high-pressure hydrogen, requiring precise and systematic risk-reduction strategies. In this study, a Hazard and Operability (HAZOP) analysis was performed for an off-site HRS, and Layer of Protection Analysis (LOPA) was conducted for four risk-level-4 events using two different approaches. The Functional Safety only LOPA, based on IEC 61511, and the All Safeguards LOPA, developed according to the Center for Chemical Process Safety (CCPS) guideline, were both applied. The Functional Safety only approach, which considers only automated protection layers, required Safety Integrity Level (SIL) ratings of 1 and 2, whereas the All Safeguards approach, accounting for mechanical and procedural protection layers, achieved the Target Mitigated Event Likelihood (TMEL) in all scenarios without additional SIL requirements. Consequently, it was confirmed that the definition of protection layer scope significantly influences the required SIL, design cost, and system complexity. This study proposes a hybrid approach in which all safeguards are considered during the early design stage, while in the final design stage, protection measures are evaluated from a functional safety perspective in accordance with IEC 61511 to ensure both design efficiency and safety integrity.

Chemicals accidents cause various hazards and a lot of damage. In order to prevent chemical accidents, various risk assessments are conducted in Korea. Among them, the Bow-tie risk assessment technique is a technique that displays the cause and effect of an accident on a line and is used widely in foreign countries. The semi-quantitative Bow-tie technique is a technique based on LOPA(Layer of Protection Analysis), which evaluates the appropriateness of protective measures derived from qualitative risk assessment. Acrylic acid is used as a main raw material for polymeric materials, and interest has been increasing due to the problems of supply and safety caused by the recent BASF fire accident. In this study, we compared the Bow-tie technique with the risk assessments currently used in Korea, and conducted a risk assessment on the polymerization process, which is the main use process of acrylic acid. As a result, a total of 8 new protective measures were derived, and it was verified by semi-quantitative Bow-tie technique. Based on the result of Bow-tie risk assessment, the acryl resin process was improved to reduce the risk. This confirms the usefulness of qualitative Bow-tie risk assessment and semi-quantitative Bow-tie risk assessment, and may be useful in other domestic chemical processes.

Layer of Protection Analysis (LOPA) has been widely adopted as a method of organizing and quantifying hazard rates. Frequently, an initial LOPA may indicate that a risk target has not been met and that a scenario requires additional layers of protection. Unlike Fault Tree Analysis, the inherent simplicity of the LOPA format makes it conducive for use directly as a problem solving tool in a team environment to close risk gaps. Teams at Air Products with representatives from operations, process controls, process design and process safety, have effectively used the LOPA format in problem‐solving sessions to identify and improve components of the analysis involving human error, controls architecture, and inherently safer process designs. This multifunctional team approach has resulted in broader ownership of the safety analysis by the full team of stakeholders, and this has ultimately led to more cost effective solutions. The benefits of multifunctional team review are illustrated with a case study example. © 2016 American Institute of Chemical Engineers Process Saf Prog 36: 257–263, 2017

Layers of protection analysis in the framework of possibility theory

Environmental quality is fundamental for the well being of human life. Environmental risk assessment and analysis have a crucial role for guaranteeing the safety of the population, especially in intensive urbanized and industrialized areas, such as the Campania region (Italy). In Italy, after the Legislative Decree 152/2006, the environmental risk assessment has become mandatory for contaminated lands such as brownfields and dismantled industrial activities. Despite the importance and fragility of the soil, it is rarely taken into account as a resource to be preserved. Moreover, due to the heterogeneity of many variables involved in the process, the environmental and human health risk assessments are used at the scale of a site, while the regional evaluation is very difficult, and keeps the administration sceptical in taking it into account for land planning and decision-making processes. During the last years, some international methodologies for ecological and human health risk assessment have been developed by national environmental agencies in many industrialized countries. An idea recently took place regarding the protection of soils: the monitoring of soil should be limited only to risk areas, as opposed to monitoring systems covering the entire territory. Focusing monitoring in selected areas would help to define priorities, increase efficiency of monitoring activities and reduce the monitoring costs. This is the reason why many methodologies for preliminary and simplified risk assessment of (potentially) contaminated sites, for the prioritization and planning of soil remediation and protection programmes, were developed. The only lack that these methodologies have is the absence of the spatial analysis. The aim of this research was to implement the human health risk assessment. For the purposes of the study we used 3535 topsoil samples, collected across the whole regional territory. The concentrations of 53 elements have been determined at Bureau Veritas Analytical Lab. Ltd (Vancouver, Canada), by means of an Aqua Regia extraction followed by a combination of ICP-MS and ICP-AES methods. After the statistical and cartographic elaboration of these regional dataset, we integrated one of the model of relative risk assessment for single contaminated sites with spatial analysis procedures. In order to support the spatial assessment of contaminated sites at the regional scale, the most suitable tool is the Geographic Information System (GIS). A new approach was applied, in order to assess/rank environmental risk by using geospatial analysis in a GIS platform to adapt a European-wide accepted methodology for the preliminary assessment of human health risks at single contaminated sites to a regional scale. The developed regional risk assessment methodology can be used by the regional administrations to select at regional level the or priority areas. The identification of the problem areas is necessary for developing an efficient monitoring system and to produce a ranking of the risky areas to be used as a reference in determining the development of intervention plans, for better addressing the resources dedicated to the environmental remediation of widely contaminated regions. The methodology chosen as a reference for the risk assessment procedures is the PRA.MS (Preliminary risk assessment model for the identification of problem areas for soil contamination in Europe, 2005). Following the PRA.MS guidelines, a conceptual model for the human health risk assessment for the Campania region has been based on four different exposure routes: 1) dispersion of contaminants in groundwater, 2) dispersion in surface water, 3) dispersion in air, 4) direct contact with the contaminated media (soils). The source, the pathway and the receptor for each of the exposure route are scored on the base of a quantitative or qualitative analysis of some featuring characteristics (parameters). A total of 14 representative parameters were chosen, basing on the available regional data for Campania. Starting from these parameters values, the information is aggregated to higher levels in several steps, adopting a mixed additive and multiplicative algorithm, up to the overall risk score. The final risk map is classified according four classes of risk. This map was useful to identify the problem areas, characterized by a higher risk, where more detailed analysis had to be carried out. The identified area was located in a wide territory in the center of Campania region, between Avellino and Salerno municipalities, an high populated zone, where intensive agricultural and industrial activities are well developed. A high density survey has been carried out in this priority area; the concentrations of 53 elements have been measured on 102 new topsoil samples, followed by statistic and cartographic elaboration of the 15 potentially toxic elements (Sb, As, Be, Cd, Co, Cr, Cu, Hg, Ni, Pb, Se, Sn, Tl, V, Zn) for which the Italian legislation (D.Lgs. 152/06) established the trigger and action limits, by defining the contamination threshold values (CSC) for the amount of metals in topsoils or waters. The new methodology of GIS-based human health risk assessment has been again applied, in order to select sites of particular significance in terms of danger for the resident population. Some small areas characterized by high risk have been identified. New in situ measurements and classic follow up risk assessment should be here carried out to confirm if remediation actions are needed to guaranteeing the safety of the population. Other works has been contemporaneously elaborated during the PhD. Six months have been spent at the Geological Survey of Finland (GTK), where a work on a humus samples dataset have been carried out, under the supervision of Dr. Timo Tarvainen. Moreover a new Geochemical Atlas will be completed based on inorganic elements and organic compounds concentrations in marine sediments samples, collected in the Gulfs of Naples and Salerno.

The paper indicates advantages (and disadvantages) of layer of protection analysis (LOPA) over other methods to support its paramount position among different process safety analysis (PSA) methods in use today. Its simplicity (using order-of-magnitude estimates for all elements that constitute an accident scenario), universality (easy adaptation to particular needs), directness to indicate the effect of risk reduction measures as well as to assess the total level of risk to be compared with the company risk tolerance criteria are strong arguments for wider application of LOPA. However, the method may have some limitations (disadvantages) in comparison to other methods and therefore different extended approaches of LOPA have been developed to overcome the problem. Those approaches include an inclusion of an expert system into accident scenario identification (ExSysLOPA), new approach to deal with uncertainty connected with input data (fuzzy LOPA) as well as for explosion at workplace risk assessment (ExLOPA). Some of these combined techniques will be presented here and they support and extend the applications of layer of protection analysis, especially for safety assurance assessment of risk-based determination that is used in oil and gas process industries.

The probability of occurring emergency situations increases in conditions of severe climate of the Arctic. Therefore, addressing the problems related to the risk assessment of accidents at oil and gas facilities in the Arctic zones based on acceptable risk criteria is of particular importance. Uncontrollable development of emergency situations is followed by emission of a significant amount of oil products and constitutes serious ecological danger, and also can lead to considerable destructions and death of people resulted from fire and explosion. Therefore, the goal of the study is development of the methods for analysis and assessment of the risk of accidents in reservoirs and gas pipelines at low temperatures to increase the industrial safety of hazardous production facilities operating in conditions of the Arctic North. The results of brittle fracture analysis and accident risk assessment for reservoir and gas pipeline under arctic climatic conditions are presented. Statistical data processing of accidents allowed us to determine the rupture sources, develop a “fault tree” of brittle fracture of reservoirs, “event trees” of reservoir explosion and gas outflow from a gas pipeline, with allowance for the frequency of scenarios for quantitative risk assessment. Currently the probabilistic approach is considered one of the most promising. Accident statistics and experience of previous risk analyses can provide a useful contribution to the process of hazard identification. We focus on the scenario approach to the problems of hazard identification and assess the probability (frequency) of emergencies proceeding from the analysis and systematization of the statistical data on the accidents on reservoirs and gas pipelines at low ambient temperatures using the “event trees” and “fault trees” which provide determination of the most critical scenario and expected risk from accidents. Thus, risk assessment of accidents at hazardous production facilities in the Arctic zone using criteria of acceptable risk will allow estimation of hazards with unacceptable level of risk and development of recommendations and measures to reduce them.

Acceptability and perception drive risky environmental heath and safety decisions: protecting against nearly infinitesimal risks can involve expenditures of millions or billions of dollars. Societal decision-makers and individual taxpayers are asked to understand numbers that span over more than 15 orders of magnitude, numbers with which most individuals lack experience. For example, we perceived real estate values will continue to rise, and lenders, in part misperceiving the potential risks of defaults, lent to more than 7 million high-risk borrowers: more than a trillion dollars were involved in the sub-prime loans market disaster. Even when public agencies or industry perform a health or safety assessment and demonstrate low risk, such assertions are not sufficient justification for those at risk to accept as minimal guarantees of safety, as the Challenger disaster shows. However, to assert that a risk is correctly perceived and acceptable requires understanding of 'acceptable risk' numbers, otherwise any 'acceptable risk criterion' to justify a choice can hardly be meaningful. This paper's synthesis of theoretical and experimental aspects integrates decision-theoretic, behavioural and neurological results, including surprising or paradoxical choices.