1,571 research outputs found
Industrial risk in the Lombardy Region (Italy): what people perceive and what are the gaps to improve the risk communication and the participatory processes
Risk communication is of vital importance in today\u2019s society, as audiences become ever more questioning about the causes and effects of risk. However, the communication of risk is a complex activity involving many different types of communicators and destinataries, from scientists, to the media, to government agencies, industry and consumer groups, each of which having its own agendas to fulfil. Such variation across the communication of the same risk can lead to confusion, misunderstandings, misreporting in the media and subsequent conflicts.
The goal of risk communication is to produce an informed public. The personal nature of risk issues and the uncertainty associated with estimating risk can provoke considerable anxiety for the public and make adopted risk management strategies less acceptable.
Lombardy is one of the most densely populated and industrialized regions in Europe and nearly 280 Seveso sites interest it. The Seveso Directive requires specific measures on risk communication to the population. Nevertheless, the Lombardy Region Authorities consider that the implementation of such provisions is too weak. Therefore an exploratory research has been concluded, in order to estimate the gaps in risk communication and to improve the participation of the population in the emergency preparedness activities.
The paper reports the main results of the research and illustrates the potential strategies to improve the risk communication and the population participation and preparedness (\uc9upolis Lombardia 2011)
Comparison between two cases study on water kiosks
Bottled water consumption in Europe began in the 70s. Environmental impact derived from water production chain is very significant: for example plastic bottles use, oil consumption for bottle production, air emission from vehicles transporting bottles, not recycled plastic packages, etc. In this research an environmental and economic impact evaluation was presented for two case studies, regarding water kiosk design with the aim of supplying controlled natural and sparkling water with better organoleptic quality compared to water directly supplied from aqueduct
Behavioral Safety: A way to decrease injuries at work (with science)
Work-related injuries are a well known problem all around European Union (EU): every year, at
least 170000 workers die and even more suffer severe and permanent injuries.
Even if EU placed the goal of reducing this number by 25% by 2012, in many countries the situation remains
unchanged despite the enforcement of increasingly stringent laws that, anyways, elude the most important
question: why?
Moreover, in spite of a lot of American and European studies demonstrated that at least 76% of work-related
accidents are due to workers unsafe behaviors, blaming workers is not a effective solution because it eludes
again the question: why a worker should act unsafe?
An answer to this last question comes from studies about human behavior: a person acts a certain way
because he is subject to a number of external stimuli, before and after his act. So, if a person receives a
positive consequence as a reward for his behavior, he continues to output the same behavior.
Till 80's, Behavior-Based Safety (B-BS) uses this mechanic to provide positive consequences to safe
behaviors, instead of negative ones, increasing safety and reducing injuries.
But does B-BS work? Even if a lot of literature case studies of successful B-BS implementation are present,
all across the world, there is a lack of scientific experiments to unequivocally state that B-BS increases safe
behaviors and reduces injuries. This work provides two different case studies, using not only a before-after
analysis but also using an appropriate mathematical test (Young\u2019s C Test), to examine workers\u2019 behavior
changes during time.
The work puts in competition two different B-BS protocols, which share all the fundamentals but differ for
start-up time and cost, applied on two different Italian industrial sites: a glass bottle factory and a paint
factory.
These protocols obtains the same results, demonstrating not only that B-BS works, but also that behavioral
safety can be achieved at low cost even for small European industries
Safe optimization of potentially runaway processes using topology based tools and software
In chemical industries, fast and strongly exothermic reactions are often to be carried out to
synthesize a number of intermediates and final desired products. Such processes can exhibit a phenomenon
known as \u201cthermal runaway\u201d that consists in a reactor temperature loss of control.
During the course of the years, lots of methods, aimed to detect the set of operating parameters (e.g., dosing
times, initial reactor temperature, coolant temperature, etc..) at which such a dangerous phenomenon can
occur, have been developed. Moreover, in the last few years, the attention has been posed on safe process
optimization, that is how to compute the set of operating parameters able to ensure high reactor productivity
and, contextually, safe conditions.
To achieve this goal, with particular reference to industrial semibatch synthesis carried out using both
isothermal and isoperibolic temperature control mode, a dedicated optimization software has been
implemented. Such a software identifies the optimum set of operating parameters using a topological
criterion able to bind the so-called \u201cQFS region\u201d (where reactants accumulation is low and all the heat
released is readily removed by the cooling equipment) and, then, iteratively searching for the constrained
system optimum. To manage the software, only a few experimental parameters are needed; essentially:
heat(s) of reaction, apparent system kinetics (Arrhenius law), threshold temperature(s) above which
unwanted side reactions, decompositions or boiling phenomena are triggered, heat transfer coefficients and
reactants heat capacities. Such parameters can be obtained using simple calorimetric techniques (DSC, ARC,
RC1, etc..). Over the optimization section, the software posses a simulation section where both normal and
upset operating conditions (such as pumps failure and external fire) can be tested
Aeraulic behaviour of a biotrickling filter pilot plant: experiments and simulations
Trickling bed biofilters (or biotrickling filters, BTFs) are biological systems for polluted air treatment. Hydrodynamics of BTFs, and reactors in general, is of paramount importance for obtaining good performances. In fact, a non-uniform distribution of the pollutant into the bed brings to dead zones or bypass which reduce the bed working volume and, therefore, cause low removal efficiencies. The paper presents the preliminary results obtained regarding the aeraulic behavior of a BTF pilot plant with seashells as packing material. Experimental results of bed void fraction and pressure drop at several flow rates were used to obtain Ergun equation coefficients for dry bed. A numerical simulation of the reactor flow field carried out with a commercial CFD (Computational Fluid Dynamics) code, validated by the means of velocity measurements made with a Hot Wire Anemometer (HWA) completed the analysis of the reactor hydrodynamics
IEC 61508: Effect of test policy on the probability of failure on demand of safety instrumented systems
Standard IEC 61508 provides probabilistic equations for determining the Average Probability of Failure on Demand (PFDavg) and the Average Probability of Failure per Hour (PFHavg) for some architectures of Safety Instrumented Systems (SIS) under the hypothesis of equal redundant components, taking into account Common Cause Failures (CCF), Detection Coverage (DC) and Proof Test Coverage (PTC) parameters. Surprisingly, IEC standard does not mention the testing policy aspects of SIS redundant
components. However, from a close examination of the probabilistic equations, it is possible to recognize that the simultaneous/sequential testing policy has been implicitly assumed. This paper describes the conditions under which the staggered testing policy - which is better than all the
others in case of independent tested components - can be advantageously applied to reduce PFDavg when CCF, DC and PTC parameters are taken into account
Modeling and simulation of an emulsion copolymerization process
Radical emulsion copolymerization is one of the most widely diffused processes aimed to produce paints easy to use because of their low viscosity. At industrial scale, such processes require a high control level of all the operating variables. Particularly, the repeatability of an emulsion polymerization process within narrow limits is one of the most desirable features because it allows for controlling also other important product qualities as final solids content, average particle size, latex viscosity and polymer average molecular weight. Other important full plant requirements are the minimization of reactants dosing times and the preparation of a latex at the highest possible concentration. In this work, the first step of a complex industrial copolymerization process has been considered. Since different monomer types (butyl acrylate, styrene, acrylic acid and acrylamide) are involved, it has been necessary to propose a complete set of rate constants for all the traditional steps of the radical emulsion
reactions chain (i.e. initiation, propagation, radicals termination, backbiting and long-chain branching,
micelles seeding, etc..). These parameters have then been inserted into a system of ordinary differential
equations expressing all balances and control actions aimed to simulate the full plant synthesis. Finally, the proposed model has been experimentally validated through the comparison with a reaction calorimetry test carried out in an indirectly cooled semibatch reactor (RC1, 1L, Mettler Toledo). Obtained results have confirmed the reliability of the theoretical model
Safe optimization of 2-octanol oxidation and vinyl acetate emulsion polymerization
In this work the possibility to develop reliable optimization procedures, particularly suitable for full plant
exothermic semibatch processes operated in the isoperibolic temperature control mode, has been
investigated. It has been found that a general optimization procedure could be developed by using a
particular curve, called topological curve, resulting from the numerical solution of the ordinary
differential equation system describing the process dynamics. Such a curve exhibits a series of
inversion points that represent, physically, transitions between different system thermal behaviour
regions.
The optimization procedure based on the analysis of the topological curve uses the QFS inversion as a
boundary beyond which the optimum operating conditions can be searched accounting for reacting
mixture thermal stability and desired productivity constraints.
Experimental temperature vs. time data spring from laboratory studies of two different potentially
runaway systems (the nitric acid oxidation of 2-octanol to 2-octanone and the free radical emulsion
homopolymerization of vinyl acetate) have been modelled to demonstrate that the topological criterion
for the QFS detection is independent of all the thermodynamic and process variables control equations
used to describe the system. Such a result suggests that this approach could be safely used to
optimize even processes operated at the full plant scale
Bacterial contamination of saline nasal irrigations in children: An original research
Microbiologic analysis of nasal saline irrigations (NSIs) used in hospitalized children was performed.
Of 253 collected samples, 24.9% were positive, and the number of positive samples significantly increased over time (P < .001). Staphylococcus aureus was the most frequently detected bacterium (28.6%). None of the 118 patients who received NSIs developed a nasosinusal infection.
Colonization by cutaneous and environmental germs is frequent and develops early. Hygienic measures should be advocated to reduce contamination
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