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771.
A value of statistical life (VSL) is used in cost-benefit analysis (CBA) as a monetary measure of the benefits to people from small risk reductions that arise from safety projects. Despite its widespread use in a number of countries, the concept of a VSL remains controversial, not least because it implies acceptance of the underlying ethical assumptions of CBA together with the idea that ‘social welfare’ can be measured and aggregated in some manner. In addition, to comply with theory, variable VSLs for different groups within society would be advocated. However, without fail, empirically, it is the case that those countries that employ a willingness to pay based approach to cost-benefit analysis of a safety project appraisal tend to use a single value for that accident context that is independent of the per capita income level, or indeed other personal characteristics, of the sub-group in society to which the safety improvement will actually apply. This article presents a straightforward, but theoretically justified adaptation to the calculation of a VSL which allows empirical practice by policymakers i.e. the application of a “common” VSL for any particular hazard within a given society, to be compatible with a CBA decision making approach. 相似文献
772.
Mario C.R. Vidal Paulo V.R. Carvalho Marcello S. Santos Isaac J.L. dos Santos 《Journal of Loss Prevention in the Process Industries》2009,22(4):516-527
This article aims to describe the characteristics of collective working situations in complex systems – especially those in nuclear power plants – related to common forms of cooperation, in order to improve systems resilience. In addition, we will try to detail some aspects of collective working situations, emphasizing the differences between various forms of control. The similarities between work activities (multi-addressed messages, linkage to regulation, central and peripheral information) are nonetheless exposed. We conclude by proposing a contribution to support systems design, thus facilitating cooperation in teamwork activities. 相似文献
773.
After three decades of sustained continuous improvement of mine safety performances in the US, mine disasters in 2006 and 2007 compromised an excellent record and presented new challenges and vulnerabilities for the underground coal mining industry. In the aftermath of the incidents, formal investigations and new scrutiny of mine safety by the US Congress and expert study groups followed. The US Congress passed the Mine Improvement and New Emergency Response Act of 2006 (MINER Act), which mandated new laws to address the issues, including those related to mine fires and explosions from which miners must be protected. The National Mining Association-sponsored Mine Safety Technology and Training Commission report highlighted the role of risk analysis and management in identifying and controlling major hazards, such as fires and explosions. In this paper an approach is given for analyzing the risks for fires and explosions based on the Mine Safety and Health Administration citation database. Using 2006 citation data and focusing on subsystem failures, the methodology is applied to a database for a pilot sample of underground coal mines stratified by mine size and state. 相似文献
774.
William R. Nelson Karl Van Scyoc 《Journal of Loss Prevention in the Process Industries》2009,22(6):764-768
Modern process plants are complex engineering systems. While thorough reviews of system safeguards are performed, catastrophic events continue to occur, often unfolding in unforeseen ways. Success in process safety demands safe processes, and understanding rare, high consequence events is central to the traditional process safety approach. This philosophy is common to all high-hazard industries, offering the potential for sharing approaches, experience, and lessons learned. The problem, however, is that people (and organizations and entire industries) who fear failure (atychiphobia) sometimes obsess about failure so much that they miss opportunities to succeed.This paper examines selected risk management practices in the power generation and aerospace industries and how those practices have led to improved performance. Risk informed decision making (RIDM) has had widespread application in the nuclear and aerospace industries, and is undergoing enhancements to become a key framework for risk management. Additionally, rather than focusing on avoidance of loss, there are emerging approaches supporting achievement of success. This approach provides a more direct link of risk to business and operational objectives, but does challenge conventional risk approaches founded in a loss prevention-centric view. The paper reflects upon risk informed decision making and success modeling, and suggests how these methods may be applied in the field of process safety. Specific examples are drawn from the defense in depth approach from the nuclear power industry and mission success concepts developed for NASA. 相似文献
775.
Attention has been focused on the treatment of lignite-fired flue gas in order to use lignite in an environmentally friendly way – (i) low-CO2 emission, (ii) production of a valuable by-product, (iii) no discharge of wastewater, (iv) direct removal of SO3 (strong toxicity), and (v) treatment of high SO2 concentration. Based on these criteria, electron beam irradiation with ammonia injection was tested on a semi-pilot scale: 800 Nm3 h?1 flow rate, 5500 ppm SO2, 70 ppm NOx, 22% flue gas moisture, and 75–80 °C at the reactor outlet.As an energy-saving measure, a low dose (5 kGy) of irradiation was applied: the problem lay in the by-product quality. It is considered that (NH4)2SO3 and NH4HSO3 produced by thermal reactions are oxidized to form (NH4)2SO4 (fertilizer) by an electron beam. However, not all reactions were complete because the by-product contained small amounts of H2SO4 and NH2SO3NH4 (herbicide), so a vegetable pot test was performed to study the by-product quality: no adverse effect was observed. It is inferred from the pot test that slightly acidic soil may protect vegetables from disease and a small amount of NH2SO3NH4 probably affects woody species and not herbaceous species.It is concluded that the electron beam system is noted as a multi-component pollution control process (removal of NOx, SO3, SO2 and dioxins) and this system will contribute to environmentally friendly use of lignite as well as agricultural productivity via fertilizer supply. 相似文献
776.
K. Walha R. Ben Amar P. Bourseau P. Jaouen 《Process Safety and Environmental Protection》2009,87(5):331-335
Tuna cooking juice from a Tunisian tuna-processing unit has a high level of polluting load: chemical oxygen demand (COD) is comprised between 4 and 20 g L−1, nitrogen kjedahl (NK) between 0.6 and 3 g L−1 and dry matter between 120 and 160 g L−1. The juice has thus to be treated before being rejected into the environment. This paper considers the nanofiltration (NF) of these concentrated organic/inorganic mixtures using an AFC 30 (NF) membrane. The work focusses on the effect of organic and inorganic matters on the permeate flux and rejections of these matters. For this purpose, mixtures of salt and organic pollution (COD), used as model solutions, were prepared by the dilution of a typical industrial tuna cooking juice. The permeate flux was found to decrease when salt and organic matter concentrations increase. The recovery rate in organic matter decreases with increasing salt or organic matter content and the recovery rate of salt decreases when the COD concentration increases. 相似文献
777.
D. Ray R. Ravindar Rao A. V. Bhoi A. K. Biswas A. K. Ganguly P. B. Sanyal 《Environmental monitoring and assessment》2000,61(3):387-398
Water Quality Survey of Rohtas district of Bihar was conducted. Samples were collected from differentsources and analysed. 209 samples were collectedfrom 196 villages. Results of water quality surveyidentified the problem areas in respect of high iron,manganese, fluoride, nitrate and brackishness of water in the district. 相似文献
778.
A.J. Wheeler I. Williams R.A. Beaumont R.S. Hamilton 《Environmental monitoring and assessment》2000,65(1-2):69-77
The personal exposure of children aged 9 – 11 years to particulate matter (PM10 and PM2.5) was carried out between January and September 1997 in the London Borough of Barnet. Personal sampling along with home, garden and classroom microenvironmental monitoring was completed for all ten children. Each child was monitored for five days during winter, spring and summer. All children completed daily time activity diaries to provide information on any potential activities that could influence their exposure to particulate matter. Each evening a household activity questionnaire was also completed by the parents. Personal Environmental Monitors were used to sample personal exposure to PM10 and PM2.5. Harvard Impactors were used for the microenvironmental sampling of both size fractions. The children's mean personal exposure concentrations for PM10 during winter, spring and summer were 72, 54 and 35 µg/m3 respectively and for PM2.5 22, 17 and 18 µg/m3 respectively. In order to determine the potential sources of particulate matter, analysis of the Teflon filters has been undertaken. The physical characteristics of the particles have been identified using Scanning Electron Microscopy. The relationships between personal exposure concentrations and the different microenvironments will be discussed. 相似文献
779.
780.
D.S. Lee R.D. Kingdon M.E. Jenkin A. Webster 《Environmental Modeling and Assessment》2000,5(2):105-118
In order to understand relationships between sources and receptors of atmospheric deposition, computer models must be used.
This paper describes a Lagrangian acid deposition model that represents emissions of trace species across Northern Europe.
The chemistry of sulphur dioxide, dimethyl sulphide and hydrogen sulphide is represented and the model tested against estimates
of UK wet and dry deposition. Mean UK wet and dry deposition for the period 1992–1994 was 206 and 145 ktonne S yr-1, respectively. The model predicted wet and dry deposition of 222 and 166 ktonne S yr-1, in good agreement with measurements. The model has been used to examine the sources of deposited S to the UK. For a base
year of 1992, 86% of the UK's SO2 emissions are exported. The S deposition attributable from mainland European sources was 36% of the UK total S deposition,
in good agreement with other UK models but this differs substantially from the calculations of the EMEP model. Natural sources
of S deposition from planktonic emissions of dimethyl sulphide, biological emissions of hydrogen sulphide and non-eruptive
volcanic emissions of sulphur dioxide contributed approximately 1% of the modelled UK S deposition, of which 95% originated
from dimethyl sulphide. The explicit chemical scheme for dimethyl sulphide incorporated into the model showed that 24% of
the resultant deposited S was methane sulphonic acid. Boundary conditions of the model were tested and it was found that initialisation
of sulphur dioxide and sulphate concentrations to representative ambient conditions had a very small effect. The modelled
contribution of UK and European sources to UK S deposition was approximately 40 and 60%, respectively, showing the dramatic
change arising from projected UK SO2 emissions in 2010.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献