World Congress on Risk 2015
19-23 July, 2015, Singapore

Online Program



Session Schedule & Abstracts


* Disclaimer: All presentations represent the views of the authors, and not the organizations that support their research. Please apply the standard disclaimer that any opinions, findings, and conclusions or recommendations in abstracts, posters, and presentations at the meeting are those of the authors and do not necessarily reflect the views of any other organization or agency. Meeting attendees and authors should be aware that this disclaimer is intended to apply to all abstracts contained in this document. Authors who wish to emphasize this disclaimer should do so in their presentation or poster. In an effort to make the abstracts as concise as possible and easy for meeting participants to read, the abstracts have been formatted such that they exclude references to papers, affiliations, and/or funding sources. Authors who wish to provide attendees with this information should do so in their presentation or poster.

Common abbreviations

Wednesday 22-07-2015

W4-F
Methods for Risk Assessment

Room: Exploration   15:30–17:00

Chair(s): N. Krishnamurthy



1    QMRA of Legionella and Mycobacterium avium in roof-harvested rainwater in Australia and the USA. Hamilton KA, Drexel University; Ahmed W, Commonwealth Scientific and Industrial Research Organization (CSIRO); Toze S, Commonwealth Scientific and Industrial Research Organization (CSIRO); Haas CN, Drexel University   kh495@drexel.edu (169)

Abstract: As a result of increased drought and climate variability, the city of Brisbane has some of the highest water restriction levels in Australia and is at the forefront of roof-harvested rainwater (RHRW) research to conserve water. Concurrently, RHRW for household use is poised for widespread expansion in Philadelphia and in the past year, over 3,500 barrels have been distributed to residents through the Philadelphia Water Department. However, due to varied approaches for rainwater collection, treatment, storage, distribution, and system maintenance, there is no consensus on the water quality or health risks from these systems. Several outbreaks of infectious diarrheal and respiratory diseases in Australia have been linked to contaminated rainwater, warranting characterization of their health risks. A pilot study is currently in progress in Philadelphia to characterize the health risks due to exposure to RHRW from waterborne pathogens Legionella pneumophila, Acanthameoba spp., and species that are part of the Mycobacterium avium complex (MAC) which are currently identified as having relevance to humans: M. avium hominissuis, M. intracellulare, and M. chimaera. Legionella and MAC are high-priority public health pathogens and are responsible for significant portions of the waterborne disease burdens in Australia and the US. Amoeba can form symbiotic relationships with these pathogens, enhancing their growth and virulence. Newly modified quantitative PCR (qPCR) assays are being developed for this work to produce a quantitative estimate of the number of gene copies of each organism in water samples for comparison with traditional culture-based methods. This information will be used as input to a quantitative microbial risk assessment (QMRA) to compare the probability of infection with these organisms and correlations with environmental factors such as rainfall, wind direction, temperature, and humidity. The QMRA will inform rainwater harvesting use practices and treatment guidance in both locations.

2    Sustainable Risk-based Approaches for Regulatory Periodic Inspections. Veeramany A, Technical Standards and Safety Authority; Mangalam S, Technical Standards and Safety Authority; Larez Jorge, Technical Standards and Safety Authority; Abraham Lency, Technical Standards and Safety Authority; Reid Dwight, Technical Standards and Safety Authority   AVEERAMANY@TSSA.ORG (292)

Abstract: Prescriptive oversight requirements in regulations such as mandated annual inspections may require regulatory authorities to allocate resources in an inefficient and unsustainable manner. This scheme is counterproductive to the management of risk to public and entails a huge ecological footprint in terms of frequent travel to remote facilities and to locations that have exhibited compliance over a long period. The problem gets exacerbated given the conflicting requirement that decision makers are required to follow prescriptive schedules and also reduce regulatory burden on the entities while optimizing available economic resources. An alternative sustainable innovation is to conduct risk-based inspections that reduce the number of inspections at facilities in a manner that ensures that the facilities are in compliance and operating in a safe manner. The objective of this paper is to describe a risk-informed methodology in determining inspection intervals through proven quantitative approaches. In the first step, a conceptual risk assessment model is developed that characterizes the potential risk of injury for observed non-compliances by quantifying the causative relationship between these deficiencies and the risk of injury. In the second step, a risk aggregation model is proposed that helps establish a facility’s operational risk based on past inspection outcomes. Finally, the facility’s operational risk is translated into an inspection interval through construction of a cumulative risk curve based on an innovative adaptation of reliability theory. The risk acceptability threshold used for the translation follows an FN-curve principle. It is varied to accommodate land use such that facilities established around regions posing less societal risk are required to be inspected less often. The threshold is relaxed through a credit system for remote facilities and those that have exhibited exceptional compliance history. The paper details the approach with application to propane facilities in Ontario.

4    The SAFER Diamond :: A Schematic for Risk Management. Krishnamurthy N., Safety Consultant   safety@profkrishna.com (281)

Abstract: In construction and other engineering industries, job safety analysis is conducted with a risk matrix of two dominant parameters probability (P) of occurrence and severity (S) of consequence. Qualitative assessment being the norm, assessor would slot various hazards into the risk matrix, with P and S levels chosen from practical considerations. When P, S levels are given ranks 1, 2, ..., risk index R is found as P.S. While this has served as a reasonable solution in a complex situation, it is inefficient in terms of standardization, statistics gathering, and comparisons across projects, industries, and countries. Author has developed a computer-based technique to eliminate subjectivity of P, S levels and to establish a quantitative approach to risk assessment. Results are presented in graphics spreadsheet, as an interactive tool for scenario analysis and decision-making for risk management. Data entry of only two feasible end points, namely least and most expected probabilities and severities of the job on hand are required. The arithmetical space will be transformed into logarithmic space so that hyperbolic risk contours will be transformed to straight lines for easier visualization. The rectangular domain will be normalized to a square with P, S, and R in familiar percentages. For convenient use, the square is rotated by 45 degrees resulting in a diamond shape with P and S axes as bottom left and right sides of the diamond, and risk R being the vertical axis through origin. Intermediate stations may be located for any combination of P and S, and resulting R may be assessed within input lowest and highest bounds of tolerable risk. The technique is patented in Singapore and Australia as 'Safe And Feasible Exponential Risk Diamond, or 'SAFER Diamond'. Patent is pending in USA. Paper will present background material, deficiencies in common current practice, and the logic and mathematics underlying the SAFER Diamond, illustrating its use with a few practical examples.



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