[Show abstract][Hide abstract] ABSTRACT: Risk management in the water utility sector is becoming increasingly explicit. However, due to the novelty and complexity of the discipline, utilities are encountering difficulties in defining and institutionalising their risk management processes. In response, the authors have developed a sector specific capability maturity methodology for benchmarking and improving risk management. The research, conducted in consultation with water utility practitioners, has distilled risk management into a coherent, process‐based framework. We identified eleven risk management processes, and eight key attributes with characterise the extent to which these processes are defined, controlled and institutionalised. Implementation of the model should enable utilities to more effectively employ their portfolio of risk analysis techniques for optimal, credible and defensible decision making.
Journal of Risk Research 02/2007; 8(1):85-104. · 0.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Risk management in the water utility sector is fast becoming explicit. Here, we describe application of a capability model to benchmark the risk management maturity of eight water utilities from the UK, Australia and the USA. Our analysis codifies risk management practice and offers practical guidance as to how utilities may more effectively employ their portfolio of risk analysis techniques for optimal, credible, and defensible decision making. For risk analysis, observed good practices include the use of initiation criteria for applying risk assessment techniques; the adoption of formalised procedures to guide their application; and auditing and peer reviews to ensure procedural compliance and provide quality assurance. Additionally, we have identified common weaknesses likely to be representative of the sector as a whole, in particular a need for improved risk knowledge management and education and training in the discipline.
Journal of Risk Research 01/2007; 10(1):105-123. · 0.88 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The goal setting regime imposed by the UK safety regulator has important implications for an organisation's ability to manage health and safety related risks. Existing approaches to safety assurance based on risk analysis and formal safety assessments are increasingly considered unlikely to create the step change improvement in safety to which the offshore industry aspires and alternative approaches are being considered. One approach, which addresses the important issue of organisational behaviour and which can be applied at a very early stage of design, is the capability maturity model (CMM). The paper describes the development of a design safety capability maturity model, outlining the key processes considered necessary to safety achievement, definition of maturity levels and scoring methods. The paper discusses how CMM is related to regulatory mechanisms and risk based decision making together with the potential of CMM to environmental risk management.
Environment International 01/2007; 32(8):1094-105. · 6.25 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Financial pressures, regulatory reform, and sectoral restructuring are requiring water utilities to move from technically inclined, risk-averse management approaches toward more commercial, business-oriented practices. Risk analysis strategies and techniques traditionally applied to public health protection are now seeing broader application for asset management, assessing competition risks, and potential threats to the security of supplies. Water utility managers have to consider these risks alongside one another, employ a range of techniques, and devise business plans that prioritize resources on the basis of risk. We present a comprehensive review of risk analysis and management strategies for application in the water utility sector at the strategic, program, and operational levels of decision making.
Critical Reviews in Environmental Science and Technology 01/2006; 36(2):85-139. · 3.38 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Risk management in the water utility sector is fast becoming an explicit paradigm. Here, we describe the application of a risk management capability maturity model to benchmark the risk management maturity of water utilities from the UK, Australia and the USA. The analysis is suggestive of capabilities in the sector as a whole and illustrates the need for improved competencies in risk management and the management of risk knowledge. Heightened level of risk management capability can be achieved by improving the risk management cultures within organisations.
Proceedings of the Water Environment Federation. 12/2005;
[Show abstract][Hide abstract] ABSTRACT: The provision of wholesome, affordable and safe drinking water that has the trust of customers is the goal of the international water utility sector. Risk management, in terms of protecting the public health from pathogenic and chemical hazards has driven and continues to drive developments within the sector. In common with much of industry, the water sector is formalizing and making explicit approaches to risk management and decision-making that have formerly been implicit. Here, we review the risk management frameworks and risk analysis tools and techniques used within the water sector, considering their application at the strategic, programme and operational levels of decision-making. Our analysis extends the application beyond that of public health to issues of financial risk management, reliability and risk-based maintenance and the application of business risk maturity models.
Process Safety and Environmental Protection 11/2004; 82(6):453–462. · 1.50 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In reliability engineering, component failures are generally classified in one of three ways: (1) early life failures; (2) failures having random onset times; and (3) late life or ‘wear out’ failures. When the time-distribution of failures of a population of components is analysed in terms of a Weibull distribution, these failure types may be associated with shape parameters β having values <1, ∼1, and >1 respectively. Early life failures are frequently attributed to poor design (e.g. poor materials selection) or problems associated with manufacturing or assembly processes.We describe a methodology for the implementation of physics-of-failure models of component lifetimes in the presence of parameter and model uncertainties. This treats uncertain parameters as random variables described by some appropriate statistical distribution, which may be sampled using Monte Carlo methods. The number of simulations required depends upon the desired accuracy of the predicted lifetime. Provided that the number of sampled variables is relatively small, an accuracy of 1–2% can be obtained using typically 1000 simulations.The resulting collection of times-to-failure are then sorted into ascending order and fitted to a Weibull distribution to obtain a shape factor β and a characteristic life-time η.Examples are given of the results obtained using three different models: (1) the Eyring–Peck (EP) model for corrosion of printed circuit boards; (2) a power-law corrosion growth (PCG) model which represents the progressive deterioration of oil and gas pipelines; and (3) a random shock-loading model of mechanical failure. It is shown that for any specific model the values of the Weibull shape parameters obtained may be strongly dependent on the degree of uncertainty of the underlying input parameters. Both the EP and PCG models can yield a wide range of values of β, from β>1, characteristic of wear-out behaviour, to β<1, characteristic of early-life failure, depending on the degree of dispersion of the uncertain parameters. If there is no uncertainty, a single, sharp value of the component lifetime is predicted, corresponding to the limit β=∞. In contrast, the shock-loading model is inherently random, and its predictions correspond closely to those of a constant hazard rate model, characterized by a value of β close to 1 for all finite degrees of parameter uncertainty.The results are discussed in the context of traditional methods for reliability analysis and conventional views on the nature of early-life failures.
Reliability Engineering [?] System Safety 06/2003; · 1.90 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The measurement of health and safety performance is an important requirement but most performance metrics are lagging indicators, measuring lost time incidents, dangerous occurrences etc. The challenge is to develop metrics that can be applied at the design stage. It is widely recognised that most accidents are influenced by the design stage, and many can be directly attributable to deficiencies in design. This paper is concerned with a design capability maturity model’, which is complementary to the design safety performance indicator model developed to apply to the design process itself. It has been developed to measure the capability of an organisation to design a safe installation, and is based on five maturity levels, ranging from level 1 (initial or learner approach) to optimised or best practice at level 5. This maturity model was originally developed for the software industry and has now been applied to offshore safety. A similar maturity model for quality assurance is now incorporated in the latest version of ISO 9004. Eleven characteristics associated with safety have been identified, in three main groups representing formal safety demonstration, safety implementation and longer term investment in safety. A maturity level is assigned to each of these characteristics and the profile produced reflects the organisation’s overall maturity in design for safety. An important aspect of the model is that it enables an organisation to establish its current level of maturity for each of the characteristics and to identify what steps are necessary to enable the organisation to progress to a higher level. The model can be used as a self assessment tool or applied through an external independent body to the different organisations involved in design (contractor’s design team, duty holder’s team etc).
ASME 2002 21st International Conference on Offshore Mechanics and Arctic Engineering; 01/2002
[Show abstract][Hide abstract] ABSTRACT: A set of accidents in the offshore engineering industry was analysed in order to generate a set of criteria that could be applied both to designs and design processes to reveal how susceptible they were to hazard. This involved two main tasks: the analysis of causation around the site of a moderately large number of accidents, and the analysis of causation around the site of a number of flawed design decisions. The accident dataset was taken from accident investigators' reports, while the design decision dataset was taken from practising designers' observations on a set of design reservations raised by a verification authority. In each case, the outcome was a set of criteria: one set concerning the way in which design elements ultimately contributed to accidents, and one set concerning the way in which the design process failed during the course of design activity. A framework in which these criteria could be applied is laid out, and the limitations of this approach in comparison with alternative approaches are discussed.
Journal of Engineering Design 06/2001; 12(2):117-129. · 1.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Many of the factors which control the rate of erosion, such as particle velocity, number of particles impacting a surface and their angle of impingement can be largely determined by the flow conditions of the system. In fact, many practical examples may be found when a change in the flow conditions has greatly increased or decreased erosion. In general where the flow direction changes rapidly (turbine blades, valves, pipe bends, etc.), erosion is usually considerably more severe than in straight pipes, though it has also been reported that local turbulence due to a roughened surface or misalignment can increase the rate of erosion damage. This paper presents experimental data on the dynamic behaviour of solid particles entrained within a gas phase in components of complex geometry. Flow conditions and local impact dynamics are quantified in order to determine areas susceptible to erosion and the probable metal loss rates. A combination of experimental techniques has been developed in order to pursue this goal. This includes a novel multi-layer paint erosion indication technique used to generate a three dimensional map of erosion damage, flow and particle visualisation, computational fluid dynamics (CFD) and metallic component erosion validation experiments. Results from the study of typical well head geometries used for oil and gas production are considered, and the benefits of using a range of complimentary techniques to study the solid particle erosion process are highlighted.
[Show abstract][Hide abstract] ABSTRACT: This paper reports progress towards the development of procedures and techniques for assessing the reliability of components at the design stage. From a fundamental understanding of the degradation and failure processes and their relation to the underlying operational, environmental, materials and design variables, the paper develops procedures to support reliability prediction of mechanical devices using an electro-mechanical actuator as a case study. The methodology is illustrated by particular reference to the process of sliding wear leading to jamming of the actuator.
ARCHIVE Proceedings of the Institution of Mechanical Engineers Part E Journal of Process Mechanical Engineering 1989-1996 (vols 01/1998; 212(4):213-224. · 0.31 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A multilayer paint erosion indication technique to produce a highly visual and accelerated map of erosion damage occurring in a three-dimensional component model has been developed. An investigation to obtain an understanding of how the paint layers eroded as a function of a number of erosion variables was performed. It was observed that the erosion rate behaviour of paint layers as a function of angle of particle impact, velocity, time and particle loading was in good agreement with previously reported material erosion behaviour of steels and other engineering materials. These results indicate that it is possible to use the multilayer paint erosion indication technique to provide a highly visual representation of erosion damage to complex component geometries. Such baseline information on the paint layer erosion behaviour should provide an opportunity to relate erosion data from geometry based erosion maps, such as those shown in Fig. 1, to realistic engineering situations.
[Show abstract][Hide abstract] ABSTRACT: Erosion-corrosion arising from sand production is increasingly recognised as a significant problem in petroleum production. When erosion and corrosion interact, they do so in such a complex manner that it is difficult to determine the rate of metal loss with sufficient accuracy for reliable prediction of equipment lifetimes.An experimental programme was carried out to study the interaction between the erosion and corrosion under typical petroleum production conditions. A C-Mn steel has been exposed to environments simulating wet and dry CO2 conditions. Erosion has been simulated by the introduction of sand particles (50–300 μm) and the influence of impact angle, velocity, particle loading and temperature has been investigated.The results demonstrated that for C-Mn steels there is a significant interaction between erosion and corrosion with the rate of metal loss from pure corrosion to erosion/corrosion increasing by 2 orders of magnitude. The use of wet CO2 increases the rate of metal loss by factor of 2–4. It has been shown that the metal recession rate at low velocity is dominated by the formation and removal of surface corrosion products.
[Show abstract][Hide abstract] ABSTRACT: A methodology for predicting the reliability of pipes and valves and for assessing the impact of testing and inspection policy on the safe life of a component is described. The method is based on the stress-strength interference model and enables a combination of physical models and engineering experience to be used to estimate means, variances and associated uncertainties in the life of a component. Particular attention is paid to modelling failures arising from underlying degradation processes. Bayesian routines are used to update the model parameters and to reduce uncertainties using inspection, monitoring or test data. The paper describes the principles of the method together with examples related to subsea gate valves and pipelines.
[Show abstract][Hide abstract] ABSTRACT: Public health protection must be the primary goal of a drinking water utility; delivered through supplying safe drinking water. For complex multi-utilities, this goal may come under pressure from the need to manage a plethora of business risks. We describe a risk management maturity model for assessing the capacity of utilities to manage business risks and comment on the importance of 'mindfulness' as a prerequisite for effective risk management.