Machinery Risk Assessment for Risk Reduction

New avenues are reviewed and discussed for preventing industrial machine-related injury by means of realistic risk evaluation and reduction processes at the design and application stages of machinery development and use. U.S. guidelines and European standards on machinery risk assessment procedures are described. Applications of risk assessment for machine-related injury risk management and teaching machine-risk control are discussed.     

Risk Assessment and Safety Evaluation Using Probabilistic Fault Tree Analysis

Risk assessment is an essential prelude to the development of accident prevention strategies in any chemical or petrochemical industry. Many techniques and methodologies such as HAZOP, failure mode effect analysis, fault tree analysis, preliminary hazard analysis, quantitative risk assessment and probabilistic safety analysis are available to conduct qualitative, quantitative, and probabilistic risk assessment. However, these methodologies are limited by: extensive data requirements, the length of study, results are not directly interpretable for decision making, simulation is often difficult, and they are applicable only at the operation or late design stage. Khan et al. (2001a) recently proposed a detailed methodology for risk assessment and safety evaluation. This methodology is simple, yet it is effective in safety and design-related decision making, and it has been applied successfully to many case studies. It is named SCAP, where S stands for safety, C and A stand for credible accident respectively, and P stands for probabilistic fault tree analysis. This paper recapitulates the SCAP methodology and demonstrates its application to a petrochemical plant.     

Approaches for Integrated Risk Assessment

Recognizing the need to enhance the effectiveness and efficiency of risk assessments globally, the World Health Organization's International Programme on Chemical Safety, the U.S. Environmental Protection Agency, the European Commission, and the Organization for Economic Cooperation and Development developed a collaborative partnership to foster integration of assessment approaches used to evaluate human health and ecological risks. The objectives of this effort included: improving understanding of the benefits of integration, identifying obstacles to the integration process, and engaging key agencies, organizations, and scientific societies to promote integration. A framework with supporting documentation was developed to describe an approach for integration. Four case studies were constructed to illustrate how integrated risk assessments might be conducted for chemical and nonchemical stressors. The concepts and approaches developed in the project were evaluated in an international workshop. The goal of this effort was international acceptance of guidance for integrated risk assessment.     

Safety Risk Assessment of Iran's Underground Coal Mines Based on Preventive and Preparative Measures

Mining is one of the most hazardous occupations all around the world, especially in underground coal mines. Analysis and management of safety risk are prerequisites toward control and increment in mines' safety. Common safety risk analyses in mines are based on the statistical data of the occurred incidents and economical aspects are usually neglected. In this study, based on a novel procedure and presentation of preventive and preparative measures, safety risk of Iran's underground coal mines' incidents was assessed and classified by taking advantage of Iran's mining experts' opinions. Among 10 significant identified incidents, methane explosion, coal dust explosion, and traffic accidents accounted for the highest levels of safety risk before adjustment, respectively. The most hazardous incidents in the adjusted risk mode were the same, but in a reverse order. Application of safety measures in three modes of preventive adjustments, preparative adjustment and both of them caused some risk reduction with the mean values of 67, 21, and 75%, respectively, thereby indicating the importance of safety risk management in underground coal mines and the preference for preventive measures in this area.     

Estimates of Lifetime Risk of Occupational Fatal Injury from Age-Specific Rates

The lifetime risk of fatal workplace injury is a critical issue in the evaluation of occupational hazards. Recently, Fosbroke, Kisner, and Myers (1997) described a metric for working lifetime risk (WLTR) to determine the probability that a worker will die due to a work-related fatal injury in a year over a certain number of years of employment. This quantity was defined assuming that the annual rate of fatal injuries will be the same each year during employment. Recognizing the fact that annual fatal injury rates differ with the age of the worker along with other factors, modification of the definition of working lifetime risk is derived. We obtain the estimates of the lifetime risk using age-categorized annual fatality rates and derive an estimate of the standard error of the WLTR estimator and a confidence interval for the WLTR. We illustrate these calculations by estimating the lifetime risk for work-related fatal injuries for workers in four high risk industries: agriculture-forestry-fishing, mining, construction, and transportation public utilities. The estimates are based on employment data from the Bureau of Labor Statistics and an updated version of fatality data from the National Traumatic Occupational Fatalities surveillance system.     

Robbery-Related Injury in Convenience Stores: Estimating Lifetime Risk and Identifying High-Risk Populations

Robbery-related injuries constitute a major risk for convenience store workers in the United States. Studies that focus on the injury outcomes associated with convenience store robbery are extremely limited in number. This is a prospective study of 1271 convenience stores in three metropolitan areas of Virginia between February 1, 1995 and September 30, 1996. The study quantifies the lifetime risk for an occupational robbery-related injury occurrence and determines the relative importance of various types of factors in the classification of high risk stores. Lifetime risk was estimated by calculating the probability in convenience stores for having one or more employee(s) sustain at least one robbery-related injury over a range of years that a store could be in operation. Results indicate that knowledge of the circumstances of the robbery are needed to maximize the identification of high risk stores. Estimated lifetime risk reaches 567 stores with an occupational robbery-related injury occurrence per 1,000 stores in operation after 45 years. This study addresses limitations of previous research by including information on clerk resistance and the number of robbers in its analysis. These two circumstantial characteristics of robbery have been previously hypothesized to be associated with robbery-related injury.     

A Study of Safety Factors for Risk Assessment of Drugs Used for Treatment of Attention Deficiency Hyperactivity Disorder in Sensitive Populations

The aim of this study was to search the literature through the library and Internet resources from pharmaceutical companies and associations to obtain pharmacoki-netic and pharmacodynamic data for six of the most used drugs for treatment of Attention Deficiency Hyperactivity Disorder (ADHD). The drugs included meth-ylphenidate, pemoline, haloperidol, bupropion, imipramine, and desipramine. The data collected allowed the evaluation of the 10X uncertainty factor, which was related to healthy adults and sensitive populations (children, elderly and health affected). Once the extensive database review was completed, the data were used to calculate a composite factor (kinetics x dynamics) for each drug. Ten of the 12 data-derived composite factors were less than 10. Therefore, incorporation of human kinetic and dynamic data into risk assessment can help to reduce the uncertainties associated with sensitive subgroups.     

The Fox River Risk Assessment Teaching Tool

In 1999 and 2000, two environmental consulting companies independently prepared risk assessments of the Lower Fox River waste site in Wisconsin. Because the two assessments produced somewhat different risk characterizations, the Association for Environmental Health & Sciences was asked by the site's Potentially Responsible Party to form a peer review panel to critique and compare the two assessments. The panel found interesting differences between the two risk assessments and recommended that their observations, together with the two risk assessments, be made available as a Teaching Tool for persons interested in conducting human and ecological risk assessments. An accompanying CD contains these and other materials useful for teaching purposes.     

Human Health Risk Assessment: Required Reading

Over the past 30 years, risk assessment has developed into a scientific discipline. It is critical that the next generation of risk assessors understand the history of our field, and recognize the numerous successes and failures that have taken place. This short Perspective identifies and describes specific books, monographs, and reports that are required reading for any nascent risk assessor.     

Framework for Human Health Risk Assessment

The views expressed in this paper are those of the authors and do not necessarily reflect the views or policies of the USEPA. The U.S. Government has the right to retain a nonexclusive royalty-free license in and to any copyright covering this article. The U.S. Environmental Protection Agency has recognized the need to develop a framework for human health risk assessment that puts a perspective on the approaches in practice throughout the Agency. In response, the USEPA's Risk Assessment Forum has begun the process of developing a framework for human health risk assessment. This paper provides some additional background to the previous review of the framework efforts and notes the Agency's extramural efforts to begin the process of integrating and harmonizing risk assessment approaches for all human health endpoints.     

In Pursuit of Safety: One-Hundred Years of Toxicological Risk Assessment

The publication in 1962 of Rachel Carson's Silent Spring marks the mid-point in a century that saw, in its first half, the emergence of public health concerns related to human exposures to chemicals, and, in its second half, the emergence of public policies to deal with those concerns. Those policies made it imperative that the scientific community come to grips with the problem of identifying exposure levels not likely to cause harm. This problem was not significantly discussed within the scientific community until the 1950s, and well-described methods for practical solutions to it did not appear until the 1970s. An important report from the National Academy of Sciences, published in 1983 (Risk Assessment in the Federal Government), provided an analysis of these emerging methods, and recommended a useful framework for the assessment and management of risk. This framework remains central to public health and regulatory decision-making. A high-level perspective is offered on events leading to and following the 1983 report. The article describes early thinking about chemical toxicity and the scientific path that thinking followed through the 20th century, and to the present.     

An Assessment of Integrated Risk Assessment

In order to promote international understanding and acceptance of the integrated risk assessment process, the World Health Organization/International Programme on Chemical Safety (WHO/IPCS), in collaboration with the U.S. Environmental Protection Agency and the Organization for Economic Cooperation and Development, initiated a number of activities related to integrated risk assessment. In this project, the WHO/IPCS defines integrated risk assessment as a science-based approach that combines the processes of risk estimation for humans, biota, and natural resources in one assessment. This article explores the strengths and weaknesses of integration as identified up to this date and the degree of acceptance of this concept by the global risk assessment/risk management community. It discusses both opportunities and impediments for further development and implementation.

The major emerging opportunities for an integrated approach stem from the increasing societal and political pressure to move away from vertebrate testing leading to a demand for scientific integrated approaches to in vitro and in vivo testing, as well as to computer simulations, in so-called Intelligent Testing Strategies. In addition, by weighing the evidence from conventional mammalian toxicology, ecotoxicology, human epidemiology, and eco-epidemiology, risk assessors could better characterize mechanisms of action and the forms of the relationships of exposures to responses. It is concluded that further demonstrations of scientific, economic and regulatory benefits of an integrated approach are needed. As risk assessment is becoming more mechanistic and molecular this may create an integrated approach based on common mechanisms and a common systems-biology approach.     

The Importance of Human Data in the Establishment of Occupational Exposure Limits

The use of animal vs. human data for the purposes of establishing human risk was examined for four pharmaceutical compounds: acetylsalicylic acid, cyclophosphamide, indomethacin and clofibric acid. Literature searches were conducted to identify preclinical and clinical data useful for the derivation of acceptable daily intakes (ADIs) from which a number of risk values including occupational exposure limits (OELs) could be calculated. OELs were calculated using human data and then again using animal data exclusively. For two compounds, ASA and clofibric acid use of animal data alone led to higher OELs (not health protective), while for indomethacin and cyclophosphamide use of animal data resulted in the same or lower OELs based on human data alone. In each case arguments were made for why the use of human data was preferred. The results of the analysis support a basic principle of risk assessment that all available data be considered     

Ecological Risk Assessment and the Precautionary Principle

The Precautionary Principle, generated during the late 1980s as a unifying principle for regulating discharge of hazardous material into the North Sea, has been broadened to include a shifting of the burden of proof to the proponent of a proposed activity, adoption of a more holistic assessment process, and encompassing all environmental management decisions, not just pollution prevention activities. We argue that the Precautionary Principle remains a management philosophy, not a substitute for risk assessment. Risk assessment is a tool for organizing information used in environmental management decisions. However, increasing attention to reducing the Type II error of risk assessment studies would significantly reduce the skepticism with which many view the risk assessment process. A critical review of default assumptions used in risk assessments, inclusion of indirect effects within an ecologically relevant spatial/temporal framework, and better communication between risk assessors and risk managers also would enhance the acceptability of the process. Risk assessment can provide a sound basis for management decisions regardless of the underlying philosophies of environmental conservation or utilitarianism, but only if the inherent biases in the risk assessment assumptions are acknowledged explicitly throughout the assessment and management processes.     

Evaluation of Environmental Risk Assessment Parameters Due to Hillslope Developments in Penang Island,Malaysia

Slope failure and soil erosion due to increased development activity in hilly areas can be catastrophic and affect the environment and humans’ well-being. This article investigates the parameters that contribute to environmental risk. Nine contributing parameters were identified. Rating the risk was proposed based on the prediction of occurrences of environmental issues and were categorized from very high (5) to very low (1) with high, medium, and low in between. The assessments were reviewed and evaluated based on rating for the chosen parameters. Maps quantifying risks were developed identifying areas of environmental risk. The overall result shows that development areas PD3 of Tanjung Bungah, and PD3, PD8, and PD9 of Paya Terubong have high rating of environmental risk. No development area is classified as very high risk or very low risk. The rating can be used to develop zones of potential high risk, and from this zoning guideline the viability can be measured for any proposed development.     

Axes of Extrapolation in Risk Assessment

Extrapolation in risk assessment involves the use of data and information to estimate or predict something that has not been measured or observed. Reasons for extrapolation include that the number of combinations of environmental stressors and possible receptors is too large to characterize risks comprehensively, that direct characterization is sometimes impossible, and that the power to characterize risk in a particular situation can be enhanced by using information obtained in other similar situations. Three types of extrapolation are common in risk assessments: biological (including between taxa and across levels of biological organization), temporal, and spatial. They can be thought of conceptually as the axes of a 3-dimensional graph defining the state space of biological, temporal, and spatial scales within which extrapolations are made. Each of these types of extrapolation can introduce uncertainties into risk assessments. Such uncertainties may be reduced through synergistic research facilitated by the sharing of methods, models, and data used by human health and ecological scientists     

Ten Years of the Relative Risk Model and Regional Scale Ecological Risk Assessment

It has been 10 years since the publication of the relative risk model (RRM) for regional scale ecological risk assessment. The approach has since been used successfully for a variety of freshwater, marine, and terrestrial environments in North America, South America, and Australia. During this period the types of stressors have been expanded to include more than contaminants. Invasive species, habitat loss, stream alteration and blockage, temperature, change in land use, and climate have been incorporated into the assessments. Major developments in the RRM have included the extensive use of geographical information systems, uncertainty analysis using Monte Carlo techniques, and its application to retrospective assessments to determine causation. The future uses of the RRM include assessments for forestry and conservation management, an increasing use in invasive species evaluation, and in sustainability. Developments in risk communication, the use of Bayesian approaches, and in uncertainty analyses are on the horizon.