Challenges in performing technical safety reviews of modifications – A case study

The aim of the present study, is to identify strengths and weaknesses of the technical safety review process at a Swedish Nuclear Power Plant (NPP). In this context, the function of safety reviews are understood as expert judgements on proposals for design modifications¹ and redesign of technical systems (i.e. commercial nuclear reactors), supported by formalised safety review processes. The chosen methodology is using two complementary methods: interviews of personnel performing safety reviews, and analysis of safety review reports from 2005 to 2009.The study shows that personal integrity is a trademark of the review staff and there are sufficient support systems to ensure high quality. The partition between primary and independent review is positive, having different focus and staff with different skills and perspectives making the reviews, which implies supplementary roles. The process contributes to “getting the right things done the right way”. The study also shows that though efficient communication, feedback, processes for continuous improvement, and “learning organizations” are well known success factors in academia, it is not that simple to implement and accomplish in real life.It is argued that future applications of safety review processes should focus more on communicating and clarifying the process and its adherent requirements, and improve the feedback system within the process.     

A societal risk study for transportation of class-3 hazmats – A case of Indian state highways

United Nations Class-3 hazardous materials (hazmats) are basically liquid products and transported in road tankers under ambient temperature and atmospheric pressure. They are mostly flammables and some of them are toxic (e.g. benzene) as well. The spillages due to collision related incidents involving the road tankers, carrying such hazmats through highways, pose not only flammability hazards due to pool fire, flash fire and vapor cloud explosion (VCE), but create substantial toxic hazards also. The paper presents the risk-based study of route evaluation of two state highways and one urban city road in western India on account of transportation of class-3 hazmats, namely benzene, toluene, p-xylene, methanol, cyclohexane and acetone. A comparative evaluation of study routes was undertaken based on their societal risks presented in terms of F–N curves and assessed against HSE, UK as well as VROM, The Netherlands risk acceptance criteria. Societal risks contribution of cyclohexane to the overall flammability risk mainly VCE is found to be the highest followed by acetone and benzene compared to other study hazmats. This is due to highly explosive nature of cyclohexane resulting into vapor cloud explosion. While acetone and methanol pool fires are likely to cause larger area of damage compared to others, benzene supersedes others as far as toxicity risk is concerned and larger evacuation area is encountered, as it poses greater Immediately Dangerous to Life or Health (IDLH) distance than others. Besides, study of initial isolation distance following an accident in case of benzene tanker found that benzene spillage requires larger initial isolation distance than others and so are the day and night protective action zone distances.     

Selection of failure frequency and its impact on risk assessment – A case study from plot plan optimisation

Facility Siting is an important phase of project development. A critical stage is plot plan optimisation, where significant potential hazards are eliminated due to equipment spacing. In addition to ensuring appropriate compliance with minimum spacing requirements, occupied building studies to achieve compliance with the requirements of API 752 and API 753 could also be undertaken to optimise safety outcomes. The studies are done in three stages, where the first stage is hazard identification, second stage is consequence assessment and the third stage is risk assessment. Third stage assessments are only carried, if the consequence based siting recommendations are not practical to implement.This paper presents the challenges in estimating risk due to process hazards with a focus on selecting right event likelihood data. A comparison is presented on the variation in predicted risk levels based on equipment failure rates and leak frequencies.Case study of a plot plan optimisation study is undertaken with DNVGL Phast Risk and the variation in risk levels up to two orders of magnitude are recorded. Challenges such as adaption of data for local conditions, consistent definitions of failure, sample size of data, applicability of data play a significant role in identifying and correctly quantifying the risk levels. Such challenges and its impact on risk quantification are presented in this paper as well as its impact on facility siting.     

Human factors integration – Bridging the gap between system designers and end-users: A case study

Within any high hazard industry such as chemical, oil and gas, rail or nuclear, it is necessary to involve system end-users within the design process if system design is to be optimised. To facilitate the identification and assessment of end user requirements it is necessary to integrate human factors (HF) into design from the start of the design lifecycle.During 2004, the author facilitated the integration of HF into a development project being implemented at a major gas processing facility on mainland Britain. The approach taken to HF integration on the project is commonly applied across the high hazard industries. This paper will provide information on this process and the benefits that this provided to the operator. Details will be provided on the approach taken in terms of:

• –Liaison between HF and other design disciplines.
• –Analysis undertaken and tools used.
• –HF topic areas covered.
• –Specific issues raised and how these were resolved.

It will demonstrate the advantage of the early integrated approach as compared to the later auditing or assurance approach sometimes taken in relation to HF.     

Making work environment auditable – A ‘critical case’ study of certified occupational health and safety management systems in Denmark

This paper discusses the impact of certification on occupational health and safety management (OHSM) systems. Most research in the field has focused on how well such systems comply with voluntary standards such as OHSAS 18001 or with national and international legislation. However, this paper shows that even in cases of compliance, the certified systems have problems dealing with a range of contemporary complex work environment issues. Furthermore, certification also transforms the kinds of topics addressed and the procedures and activities applied in the system. Using the (in many ways successful) development of certified OHSM system in a manufacturing company in Denmark as a critical case, we demonstrate how certified OHSM systems unintentionally yet actively create an environment of ‘measurable and auditable facts’ shaped not only in response to legal and market demands for a safe work environment, but also as a consequence of the external demands for a visible and accountable work environment standard. We show how certified OHSM systems function like a hinge between internal operations and an external audience in a globalized market, thus giving priority to work environment issues that may later become demonstrable guarantees for a safe and healthy work environment. Thus the certified management system does not necessarily tackle the most urgent work environment issues and may exclude important aspects of the work environment such as psychosocial factors.     

The role of standardization in safety management – A case study of a major oil & gas company

This article discusses the strengths and weaknesses of various kinds of standardization, when applied to the field of safety management. Recently, there are signs that organizations operating in high risk environments take further steps towards standardization. On the positive side, standardization has the potential to enhance the predictability of normal operations as well as facilitating the transfer of lessons learnt across organizational contexts. On the negative side, standardization is by definition a strategy for dealing with known hazards and accident scenarios. We discuss how too strong an emphasis on standardization can involve unintended negative consequences for organizations’ crisis-handling capabilities.     

Planning for resilient collaboration at a new petroleum installation – A case study of a coaching approach

The current paper reports the case study of a coaching process assisting an oil company in exploring how to establish a potential for resilient collaboration. When a new petroleum installation is being prepared for operation, a range of decisions is made that impacts the possibility for achieving resilient collaboration, i.e., collaboration that is sufficiently robust and flexible to work efficiently and safely across the various operational states that may arise, within the organization. It is, thus, of key importance that issues related to resilient collaboration – what collaboration should be like and how to achieve the desired way of collaborating – are addressed from an early point in the preparatory phase, to increase the likelihood that e.g., the work processes, tools and technologies, established jointly will come to promote the resilient collaboration. The purpose of the present study was to assess whether a coaching approach called, Coaching for Resilient Collaboration in IO (CORECIO), would be able to promote reflections about what resilient collaboration should imply in a planned organization, and help achieve alignment about this, in the early part of the preparatory process. Eight employees involved in preparing for operation of the new petroleum installation participated in the study, which involved the conduction of five workshops. The paper addresses strengths and limitations of CORECIO, and suggests how coaching might constitute a useful approach for assisting highly skilled professionals in preparing for resilient collaboration at a new petroleum installation in the early, conceptual, part of a design phase.     

Investigation of accidents involving powered two wheelers and bicycles – A European in-depth study

Introduction: The number of road fatalities have been falling throughout the European Union (EU) over the past 20 years and most Member States have achieved an overall reduction. Research has mainly focused on protecting car occupants, with car occupant fatalities reducing significantly. However, recently there has been a plateauing in fatalities amongst ‘Vulnerable Road Users’ (VRUs), and in 2016 accidents involving VRUs accounted for nearly half of all EU road deaths. Method: The SaferWheels study collected in-depth data on 500 accidents involving Powered Two-Wheelers (PTWs) and bicycles across six European countries. A standard in-depth accident investigation methodology was used by each team. The Driver Reliability and Error Analysis Method (DREAM) was used to systematically classify accident causation factors. Results: The most common causal factors related to errors in observation by the PTW/bicycle rider or the driver of the other vehicle, typically called ‘looked but failed to see’ accidents. Common scenarios involved the other vehicle turning or crossing in front of the PTW/bicycle. A quarter of serious or fatal injuries to PTW riders occurred in accidents where the rider lost control with no other vehicle involvement. Conclusions: Highly detailed data have been collected for 500 accidents involving PTWs or bicycles in the EU. These data can be further analyzed by researchers on a case-study basis to gain detailed insights on such accidents. Preliminary analysis suggests that ‘looked but failed to see’ remains a common cause, and in many cases the actions of the other vehicle were the critical factor, though PTW rider speed or inexperience played a role in some cases. Practical Applications: The collected data can be analyzed to better understand the characteristics and causes of accidents involving PTWs and bicycles in the EU. The results can be used to develop policies aimed at reducing road deaths and injuries to VRUs.     

Dispersion modeling of LNG-Vapor on land – A CFD-Model evaluation study

Based on methane from renewable resources, LNG is an alternative fuel for heavy and long-distance traffic in land transport. Contrary to its positive properties, the fuel contains risks from an explosion and extremely low temperatures for personal and infrastructure safety. CFD-models are suitable for doing risk analyses for arbitrary scenarios. For examining how to model for risk research the dispersion of LNG-vapor, this paper contains a model variant study, with an evaluation by experiments.This paper describes the use of the CFD-code ANSYS Fluent for simulating experiments of the ‘LNG Safety Program Phase II‘. The content of the well-documented experiments was the research of the vaporization rate of LNG on land and the dispersion of LNG-vapor in the air. Based on the comparison to two experiments, overall 12 CFD-model variants with varying thermal and turbulence parameters were examined how they affect the transient LNG-vapor dispersion in air.The definition of turbulence-boundary-condition at the domain borders had the biggest impact on modeling, followed by the turbulence model. The most accurate model variant had been applied for observing the spreading behavior of LNG-vapor in the air after evaporation on land and analyzing the influence of the LNG-composition to the dispersion. The results show that the mixture of LNG-vapor and the air in the free field is cooler than the ambient air and spreads like a heavy gas on the ground.     

The role of component arrangement in complex safety instrumented systems—A case study

The arrangement of components plays a key role in the performance of complex Safety Instrumented Systems (SIS), in which a SIS logic solver is interlocked with other logic solvers, to share a final element, for instance. The position of the components and the way they are utilized affects the reliability characteristics, such as the Probability of Failure on Demand (PFD), Spurious Trip Rate (STR), architectural sensitivity and model uncertainty. This case study uses quantitative and qualitative approaches to elaborate on various aspects of component arrangement in complex SIS. Numerous simplified models are analyzed; new classification is introduced for SIS components based on their response to demand; a set of guidelines are developed for SIS architecture design, with a focus on component arrangement; and the use of these guidelines is demonstrated in a real-life example, where an existing turbine SIS is modified to incorporate a new over-speed protection system. The simplified models and the turbine upgrade project are also used to explain the issue of unknowns and uncertainties in reliability analysis and how these issues can be addressed in SIS architecture by optimizing component arrangement.     

The role of drug and alcohol use and the risk of motor vehicle crashes in Shiraz,Iran, 2014: A case–crossover study

Background: Traffic accidents and traffic-related injuries and mortality have become a major public health concern in Iran. This study aimed to examine the role of drug and alcohol use in motor vehicle accidents in Iran.

Methods: This case–crossover study was conducted on 441 drivers who survived a road traffic crash and were taken to the emergency department of Shahid Rajaee trauma hospital in Shiraz, southern Iran. Data were collected using checklists that included demographic characteristics and drug and alcohol use prior to driving. Alcohol and drug use was identified through self-report, and cannabis, morphine, and methamphetamine urine tests were used to confirm drug abuse among drivers.

Results: In total 17.9% of drivers reported using drugs (cannabis, opium, or metamphetamine) and 8.84% of drivers reported consuming alcohol prior to the collision. The crude odds ratios (ORs) for having a crash for opium, cannabis, and metamphetamine were 1.94 (95% interval confidence [CI], 1.11–3.38), 2.37 (95% CI, 1.03–5.42), 5.5 (95% CI, 1.21–24.81), respectively, and for all drugs was 3.83 (95% CI, 2.28–6.43). The OR for alcohol was 3.5 (95% CI, 1.73–7.06) based on self-report.

Conclusion: Drug and alcohol use are increasing the risk of traffic crashes in Iran. Risk-reducing programs must be designed and implemented.     

Severity analysis of Indian coal mine accidents – A retrospective study for 100 years

A retrospective study on severity analysis of Indian coal mines accidents for 100 years was done considering fatal and serious accidents and the resulting causalities. The impact of recommendations based on safety conferences and committees over the years was studied. An event evaluation algorithm (EEA) was developed for this purpose. The hazard rate functions and cumulative risk functions for major hazards in Indian coal mines were developed. The study evaluated the status of safety level as well as the scope of improvement for Indian coal mines safety.     

Pb(II) adsorption from aqueous solutions by raw and treated biomass of maize stover – A comparative study

The potential to remove Pb(II) ion from wastewater treatment systems using raw and treated maize stover through adsorption was investigated in batch experiments. To achieve this, batch mode experiments were conducted choosing specific parameters such as pH (2–8), dosage concentration (2–30 g L⁻¹), contact time (5–180 min), temperature (20–45 °C) and metal ion concentrations (10–50 mg L⁻¹). Adsorption was pH-dependent showing a maximum at pH value 5. The equilibrium sorption capacities of raw and treated maize stover were 19.65 and 27.10 mg g⁻¹, respectively. The adsorption data fitted well to the Langmuir isotherm model. Kinetic studies revealed that the adsorption process followed pseudo-second-order model. The calculated thermodynamic parameters showed that the adsorption of Pb(II) was spontaneous and exothermic in nature. Consequently, this study demonstrated that both raw and treated maize stover could be used as adsorbents for the treatment of Pb(II) from industrial wastewaters.     

Driver distraction by digital billboards? Structural equation modeling based on naturalistic driving study data: A case study of Iran

Introduction: Digital billboards (DBs) are a competing factor for attracting drivers’ attention; evidence shows that DBs may cause crashes and vehicle conflicts because they catch drivers’ attention. Because of the complexity of a system that includes road conditions, driver features, and environmental factors, it is simply not possible to identify relationships between these factors. Thus, the present study was conducted to provide a well-organized procedure to analyze the effects of DBs on drivers’ behavior and measure factors responsible for drivers’ distraction in Babol, Iran, as a case study. Method: Corresponding data were collected through a Naturalistic Driving Study (NDS) of 78 participants when facing DBs (1,326 samples). These data were analyzed by applying structural equation modeling (SEM) to concurrently recognize relationships between endogenous and exogenous variables. Human, environmental, and road factors were determined as exogenous latent variables in a model to evaluate their influences on drivers’ distraction as an endogenous variable. Results: The results showed that road, environmental, and human factors reciprocally interact with drivers’ distraction, although the estimated coefficient of human factors was more of a factor than that of the other groups. Furthermore, younger drivers, beginner drivers, and male drivers (as human factors); night and unclear weather like a rainy day (as environmental factors); and installing DBs at complicated traffic positions like near-intersections (as road factors) were determined to be the main factors that increase the possibility of drivers’ distraction. Finally, model assessment was suggested using the goodness-of-fit indices.     

Beyond “best practice” road safety thinking and systems management – A case for culture change research

Forecasts of an “explosion” in the level of road trauma as many of the world’s most populous nations rapidly motorise have contributed to the urgency of documenting best practice thinking and management systems to improve road safety performance. By examining the success stories of nations with either the lowest fatailty rates per head of population or with the largest recent improvements a number of “lessons” have emerged. Data-driven problem identification and the development of evidence-driven countermeasure packages formalised in a strategy for effective implementation, with ambitious, quantitative targets and transparent lines of institutional accountability are the critical success factors. Basing this planning upon the cornerstones of the safe system conceptual model constitutes best practice thinking. This paper argues that critical elements of the safe system model are in discord with behavioural mores in the cultures of many western motorised nations and that this hampers the adoption of the most effective safety programs within key institutions and within political systems. A case is made for a systematic examination of car use and safety cultures in order to add a further dimension to best practice learnings.     

Numerical investigation and analysis of indoor gas explosion: A case study of “6·13” major gas explosion accident in Hubei Province,China

Taking the ' 6·13 ′ major gas explosion accident in Shiyan, Hubei Province, China as an example, three problems were studied in this work: (1)The determination of the volume of natural gas involved in the explosion; (2)The propagation process of shock wave inside the building and the damage evolution process of the accident-related building; (3)The overpressure and fragment injury to the person outside the building. Through the numerical simulation in ANSYS/LS-DYNA software, the volume of natural gas involved in the explosion is determined to be 10240 × 1400 × 400 cm (length × width × height) from three perspectives: the damage to the building, the distribution of overpressure inside the building, and the TNT equivalent of the explosion energy. The simulation results are in good line with the accident, which verifies the effectiveness of the scheme and the accuracy of the numerical model. Based on the reasonable filling scheme, the propagation process of shock waves inside the building, the damage evolution process of the building, and the injury ranges of overpressure and fragments outside the building are analyzed. It can be found that the propagation of shock waves in confined space is complex and variable. The explosion shock waves are first reflected and superimposed in the watercourse, resulting in pressure rise. At about 8ms, the shock waves rushed into the first-floor space of the building, and the maximum overpressure was about 0.56 MPa. At about 50 ms, the shock waves rushed into the second-floor space, and the maximum overpressure was about 0.139 MPa. The first and second-floor slabs and infilled walls were almost completely destroyed. The interior walls of the infilled walls are mainly collapsed, and the exterior walls are ejection around the building as the center. The peak displacement and peak velocity of the interior walls of each floor are about 15% of the exterior walls. The fragments which cause fragment injury mainly come from the retaining wall above the watercourse, the maximum velocity is about 89 m/s, and the maximum displacement is 8.9 m. The safety distance of fragment injury is about 8.8 m, while the safety distance of overpressure injury is about 4.6 m. The lethal distance of fragment injury is greater than that of overpressure injury. Compared with the distance between different damage levels of overpressure injury, the difference in fragment injury is small. Therefore, the safety assessment at the engineering level only needs to consider the safety distance of fragment injury. This study can provide suggestions for evaluating the damage of natural gas cloud explosions in confined spaces and is helpful for accident investigation and safety protection.     

Modelling of pitting corrosion in marine and offshore steel structures – A technical review

Corrosion is a major cause of structural deterioration in marine and offshore structures. It affects the life of process equipment and pipelines, and can result in structural failure, leakage, product loss, environmental pollution and the loss of life. Pitting corrosion is regarded as one of the most hazardous forms of corrosion for marine and offshore structures. The total loss of the structure might be very small, but local rate of attack can be very large and can lead to early catastrophic failure. Pitting corrosion is a localized accelerated dissolution of metal that occurs as a result of a breakdown in the protective passive film on the metal surface. It has been studied for many years; however, the structural failure due to pit characteristics is still not fully understood. Accurate pit depth measurements, precise strength assessment techniques, risk analysis due to pitting, and the mathematical relationship of the environmental factors that causes pitting failure are also factors, which need further understanding. Hence this paper focuses on these issues. It reviews and analyses the current understanding of the pitting corrosion mechanism and investigates all possible factors that can cause pitting corrosion. Furthermore, different techniques employed by scientists and researchers to identify and model the pitting corrosion are also reviewed and analysed. Future work should involve an in-depth scientific study of the corrosion mechanism and an engineering predictive model is recommended in order to assess failure, and thereby attempt to increase the remaining life of offshore assets.     

A little knowledge is a dangerous thing – Unexpected reaction case studies make the case for technical discipline

The old saying, “what you don't know can't hurt you,” implies that ignorance is bliss. “A little knowledge is a dangerous thing,” may be closer to the truth; however, it is not the little that we know that is dangerous, but that which is not known. By design, the processes used in the chemical industry are reactive, and the intended reaction receives much scrutiny. However, other reactions occur, often unexpectedly, and possibly with severe consequences. The lessons we learn from these reactions must drive the improvement of our process development and technology management processes and the culture that shapes those processes, a culture of Technical Discipline.Technical Discipline, analogous to Operating Discipline in the manufacturing organization, is a culture committed to fully identifying and characterizing chemical and reaction hazards, and properly documenting and communicating those hazards to create a permanent knowledge and understanding within the organization operating that process.A culture of Technical Discipline will reveal reaction hazards that might otherwise remain unknown until being unveiled in a dramatic and unexpected fashion. Until you fully identify and characterize the hazards of the materials you handle in your processes…what you don't know can hurt you.     

Risk factors for being the at-fault driver: A case–control study

Objective: It is estimated that road traffic accidents are globally responsible for approximately 1.2 million deaths and 20 to 50 million injuries. About 70% of traffic incidences (TIs) occur in developing countries and among countries with high TI rates; Iran is the first. The aim of this study was to measure the association between being responsible for a traffic accident and some vehicle, human; and environmental related factors in Yasuj, a city with a high incidence of road traffic injuries and deaths in Iran.

Methods: This is a time-, date-, and place-matched case–control study conducted in 2015 using all traffic accidents registered and investigated by police during 2012. In total, 194 drivers were considered the at-fault driver in a traffic accident and the 194 drivers in the same collisions were included in the analysis.

Results: Based on the results from multivariate conditional logistic regression, significant associations between vehicle maneuver (OR_{Turn to right or left/Moving forward} = 11.10, 95% confidence interval [CI], 1.77–69.58, P = .01) and age (odds ratio [OR] = 1.11, 95% CI, 1.004–1.22, P = .04) and the chance of being an at-fault driver were found.

Conclusion: Driver behavior–related interventions including training and law enforcement seem to be more effective in reducing road traffic accidents in Iran.     

Does longevity impact the severity of traffic crashes? A comparative study of young-older and old-older drivers

Introduction: This article analyzes the effect of driver’s age in crash severity with a particular focus on those over the age of 65. The greater frequency and longevity of older drivers around the world suggests the need to introduce a possible segmentation within this group at risk, thus eliminating the generic interval of 65 and over as applied today in road safety data and in the automobile insurance sector. Method: We investigate differences in the severity of traffic crashes among two subgroups of older drivers –young-older (65–75) and old-older (75+), and findings are compared with the age interval of drivers under 65. Here, we draw on data for 2016 provided by Spanish Traffic Authority. Parametric and semi-parametric regression models are applied. Results: We identified the factors related to the crash, vehicle, and driver that have a significant impact on the probability of the crash being slight, serious, or fatal for the different age groups. Conclusions: We found that crash severity and the expected costs of crashes significantly increase when the driver is over the age of 75. Practical Applications: Our results have obvious implications for regulators responsible for road safety policies – most specifically as they consider there should be specific driver licensing requirements and driving training for elderly – and for the automobile insurance industry, which to date has not examined the impact that the longevity of drivers is likely to have on their balance sheets.