Showing papers in "Journal of Loss Prevention in The Process Industries in 1996"

Coal dust explosibility

Abstract: This paper reports US Bureau of Mines (USBM) research on the explosibility of coal dusts. The purpose of this work is to improve safety in mining and other industries that process or use coal. Most of the tests were conducted in the USBM 20 litre laboratory explosibility chamber. The laboratory data show relatively good agreement with those from full-scale experimental mine tests. The parameters measured included minimum explosible concentrations, maximum explosion pressures, maximum rates of pressure rise, minimum oxygen concentrations, and amounts of limestone rock dust required to inert the coals. The effects of coal volatility and particle size were evaluated, and particle size was determined to be at least as important as volatility in determining the explosion hazard. For all coals tested, the finest sizes were the most hazardous. The coal dust explosibility data are compared to those of other hydrocarbons, such as polyethylene dust and methane gas, in an attempt to understand better the basics of coal combustion.

Dust explosions in spherical vessels: The role of flame thickness in the validity of the ‘cube-root law’

Abstract: A well known limitation of the ‘cube-root law’ is that it becomes invalid when the flame thickness is significant with respect to the vessel radius. In the literature, flame thicknesses in dust-air mixtures ranging from 15 to 80 cm have been reported, which exceed the radii of the 20 litre sphere and the 1 m3 vessel. Therefore, we have developed a model (the three-zone model) for the pressure evolution of confined dust explosions in spherical vessels which takes the flame thickness into account. The pressure-time curves that are generated with this model show a good resemblance with those measured in practice. It is shown by numerical simulations that the maximum rate of pressure rise can be normalized with respect to the vessel volume as well as to the flame thickness and that the ‘cube-root law’ becomes inaccurate for relative flame thicknesses exceeding 1%. Furthermore, the actual burning velocity and the flame thickness during real dust explosions can be obtained by fitting the model to the experimental pressure-time curve.

Measures of safety management performance and attitudes to safety at major hazard sites

Abstract: This paper describes the application of a Safety Attitude Survey Questionnaire and a Process Safety Management System (PSMS) audit tool at six major hazard sites in four European countries. The tools provide quantitative measures of safety attitudes and PSMS performance respectively. The work compares these quantitative measures with accident performance data for the six sites. The work also considers the use of generic failure rate data used in quantified risk assessment for major hazards within the context of land-use planning around the major hazard sites, and the variation in accident performance data and safety attitudes of different sites.

Determination of technical safety indices and factors influencing hazard evaluation of dusts

Abstract: A knowledge of material safety properties is an essential requirement for the safe handling of unit operations. Incidents in plants can often be traced to an insufficient knowledge of the hazardous properties of combustible substances. Unforeseen violent reactions in which destructive energies or large amounts of hazardous materials were released have resulted. Safety properties provide information on the reaction behaviour of the substances and possible fire and explosion hazards, presupposing that they are determined carefully and applied properly. The paper provides definitions of the material safety properties and brief descriptions of their methods of determination, which should be standardized internationally if at all possible, and describes various evaluation criteria. The analysis distinguishes between dust layers and dust suspensions.

Prevention and mitigation of dust explosions in the process industries: A survey of recent research and development

Abstract: The paper covers three aspects, viz basic research, applied research and development on prevention and mitigation of dust explosions in industrial practice, and testing of ignitability and explosibility of dusts With few exceptions, only works published from 1990 and onwards are referenced, ie publications that are not discussed in the previous survey (Eckhoff: ‘Dust Explosions in the Process Industries’, 1991) Increased knowledge about the numerous facets of the dust explosion hazard has created a justified request for a more differentiated approach to the design of preventive and mitigatory measures in industry In this process, cross-fertilization between fundamental research and applied research and development is essential Computer simulation models, carefully calibrated against experiments, will become useful tools in a not too distant future The use of expert systems requires adequate quality assurance

Hazards from propane BLEVEs: An update and proposal for emergency responders

Abstract: Recent fire tests of 400-litre automotive propane tanks has provided some new data on hazards from boiling liquid expanding vapour explosions (BLEVEs). Of the 40 fire tests conducted, 13 resulted in BLEVEs. The hazards from these included fireballs, projectiles and blast. This paper presents a simple analysis of the projectile hazards and compares the results with other projectile data from fire tests and accidents ending with BLEVEs. Then, the projectile hazards are compared with existing correlations for the hazards from blast and fireballs. Finally, a proposal is presented for working distances as a function of tank scale, for emergency responders dealing with potential propane or LPG BLEVEs. Projectile, blast and fireball hazard distances have been normalized in terms of a single distance unit — fireball radii. When presented in this way the hazards from a BLEVE can be summarized together, for various tank scales, in a simple and logical way. The proposal applies to accidents where a propane or LPG tank has suffered a significant loss of strength and therefore a BLEVE is possible. The loss of strength may be due to impact damage, or severe fire exposure. In this situation it is proposed that emergency responders should set up an observation position upwind and to the side (not the ends) of a damaged tank, at a position no closer than four fireball radii, to a minimum of 90 m. In this case the fireball radii has been calculated from the expression R = 3 m0.33, where m is the propane mass in kg, and R is the fireball radii in metres. At this position the responders will be reasonably safe from fireball, blast and projectile effects. At 4R, the radiant heat flux should be less than 21 k W m−2, the blast should be less than 30 mbar, and most (80–90%) projectiles should fall short of this distance. However, some projectiles can and will go further than four fireball radii and therefore responders are urged to stay further back if possible. The public should be evacuated to a minimum distance of 15 fireball radii, 30 if possible.

Experimental determination of the droplet size and velocity distributions at the exit of the bottom discharge pipe of a liquefied propane storage tank during a sudden blowdown

Abstract: In 1991, the Commission of the European Communities launched a series of projects specifically aimed at the understanding of chemical hazards. This was called the STEP Program and covered projects on hazard analysis to determine the consequences of releases of flammable pressurized and liquefied gases. In that frame, the present study concerns the experimental determination of the droplet size and velocity distributions within a jet at the exit of a discharge pipe of a liquefied propane storage tank during a sudden blowdown. For this purpose, a Phase Doppler Particle Analyzer (PDPA) was used to measure liquid drop size and velocity. Due to the high drop concentration in the jet, it was necessary to protect the incident laser beams and the light scattered by particles to make the measurements possible. In such conditions, a set of blowdowns was performed by varying the nozzle diameter, the initial pressure inside the storage vessel and the measurement position in the jet. These tests include on- and off-axis measurements. The results are presented, showing the droplet evaporation and the velocity evolution inside the jet. This work provides original data which can be useful for the validation of vapour cloud dispersion codes.

Side-vented gas explosions in a long vessel: the effect of vent position

Abstract: Currently, the experimental data on the influence of vent position on the overpressure development during gas explosions in large length to diameter ratio (L/D) vessels are very sparse. Design guides such as NFPA 68 recommend the use of side-venting, but this is based on few experimental data and it was the objective of the present work to provide further information on vented explosions in tube configurations with side vents. Methane-air explosions (10 gas by volume) were undertaken in large L/D vessels and the influence of the side-venting position relative to the spark was investigated and compared with end-venting. The pressure development during side-venting was investigated and five stages of the explosion development were identified. The five pressure peaks were identified as follows: P1 due to the initial elongated flame acceleration, P2 due to the turbulence flame acceleration in the downstream gases ahead of the flame set in motion by the initial explosion gas expansion, P3 due to the flame acceleration around the 90° bend of the side vent, P4 due to the external gas cloud explosion downstream of the vent, and P5 due to the oscillatory combustion of trapped unburnt mixture in the vessel between the side vent and the far end of the tube. All these pressure peaks were not present for each vent position and the effect depended on the distance of the side vent from the ignition source. Very high flame speeds and overpressures were measured as the distance between the side vent position and the spark was increased. In the end-venting explosions the maximum overpressure was higher than the side-vented tests, except for the case where the side vent was placed at the middle of the vessel, which had a similar overpressure to end-venting. Induced gas velocities were also measured and associated turbulent parameters were calculated and were found to increase with an increase in the distance of the vent position from the spark.

Mechanisms of flame propagation through combustible particle clouds

Abstract: An experimental study has been conducted on the mechanisms of flame propagation through combustible solid particle clouds of 1-octadecanol. The combustible particle cloud is ignited in its centre by an electric spark, and the growth of flame kernel is observed with a CCD video camera. The direct light emission and schlieren images of propagating flame and the laser light scattering images of particles have been simultaneously recorded. After ignition, a flame kernel is observed to grow with a yellow luminous zone whose outline is of an irregular shape. At the same time, a smooth shaped schlieren front is observed to propagate at 4–8 mm ahead of the outline of the yellow luminous zone. Inside the schlieren front, dispersed blue flame spots appear but no smaller particles can be seen, and only bigger particles are observed in the border region near the schlieren front. Across the schlieren front, smaller particles (most of them are about 10–20 μm in diameter) rapidly gasify just behind the schlieren front, while the gasification of particles with a diameter larger than 80 μm is delayed and the vapour lumps formed behind the schlieren front ignite to form circular dispersed blue flames. It has also been revealed that the average propagation velocity of the schlieren front increases with the number density of smaller particles, while it is scarcely affected by the mean diameter of combustible particle clouds. This fact implies that flame propagation is mainly supported by the combustion of smaller particles gasifying across the schlieren front.

Improved guidelines for the sizing of vents in dust explosions

Abstract: Current vent sizing guidelines, developed both in Europe (VDI 3673) and in the United States (NFPA 68) for the protection of equipment and buildings from dust explosions, rely on statistical regressions of test data. This leads to limitations in the range of applicability of the design methods, and, in some cases, to questionable scaling of the results. Analysis of available experimental information with knowledge derived from models of vented explosions offers a suitable alternative which can overcome these problems. An effort based on this approach has produced significant improvements in several aspects of explosion vent sizing, including: vent duct and panel inertia effects, partial volume deflagrations, venting of equipment inside buildings, and explosions at initial elevated pressure. The output of this work has been incorporated in revised vent sizing guidelines which are used by Factory Mutual Engineering Association (FMEA) loss prevention consultants in the development of loss prevention recommendations for industrial and commercial properties. This paper discusses the development of the guidelines, with emphasis on the aspects in which they significantly differ from the guidance provided by other published methods.

Prediction of explosion pressures in confined spaces

Abstract: This paper outlines the basic features of a numerical explosion model that has been developed for predicting explosion pressures and flame speeds in confined geometries. The results and lessons learnt from the validation of the model against experimental data are presented, together with a discussion of the limitations of the model and areas where further development work is required.

Dust explosions in interconnected vented vessels

Abstract: Explosion venting is used often to protect industrial dust-handling plant from pressures generated by accidental dust explosions. Many calculation methods are available to estimate a safe vent area, but these are without exception applicable to single vessels. In industry, vessels are usually linked and flames can travel through connecting pipework from one vessel to another. The behaviour of flames in such configurations is not well understood and the pressures that can be developed are not well known. As a result, the venting requirements are difficult to estimate. This report describes a project in which the behaviour of dust explosions in linked vented vessel systems was studied. Vessels ranging in size from 2 to 20 m3 were used, linked via pipes up to 15 m long with diameters of 0.15, 0.25 and 0.5 m. Tests were carried out using coal dust, toner dust and anthraquinone dust. The work has shown that the passage of flame from the primary ignition vessel can result in a secondary explosion which produces a much higher pressure than expected from a vented single vessel. Secondary explosion pressures up to 6.2 bar were recorded. The pressure in the first vessel was also enhanced but to a lesser degree. These effects were dependent on the pipe diameter, the pipe length, the vessel volumes and volume ratio, the vessel in which the explosion was initiated, the explosibility of the dust, and the vent area. Effectively, the Kst nomograph approach for sizing the vent area was found to be adequate for vessels linked via the 0.15 m diameter pipe using coal or toner dust. However, explosions in vessels linked by pipes having larger diameters (0.5 and 0.25 m) and a short length generated enhanced reduced explosion pressures. The pressure enhancement was greatest when the primary ignition occurred in the larger of the two vessels. The vessel volume ratio tended to increase the pressure enhancement. Also, the larger the vessel volume for a volume ratio of 1:1, the greater was the pressure enhancement. The more reactive dusts, toner and anthraquinone, generally produced significantly higher reduced explosion pressures in equivalent vessel/pipe configurations when compared with coal. Larger vent areas generated lower absolute pressure than the smaller vent areas.

Suppressants for the control of industrial explosions

Abstract: Explosion suppression is now a well established means of mitigation against the consequences of a gas or dust explosion in industrial processing. Such systems were first deployed by Graviner Ltd (Maisey, H.R. Chem. Process Eng., March 1959) in the early 1950s following development of the technology for military purposes. The first industrial explosion suppression systems used proprietary halons as the explosion suppressant. By the mid-1970s, dry chemical power suppressants were becoming established as the preferred suppressant because of their superior suppression performance. Today water and halon suppressants are only deployed where they offer specific benefits over the dry chemical powders. The Montreal Protocol (UNEP, Sept. 1987 amended 1991 & 1992) has imposed controls on the availability of most halons—a production ban came into effect in the UK on 1 January 1994—because these agents have a proven ozone-depleting effect in the upper atmosphere. Not surprisingly, the chemical industry has identified a range of alternative agents that are environmentally friendly and have fire-extinguishing properties. Some of these agents are now being assessed as options for explosion suppression. This paper considers the demand on an explosion suppressant and contrasts the effectiveness of available suppressant agents against industrial explosions.

Blowdown of carbon dioxide from initially supercritical conditions

Abstract: The paper presents experimental investigations of the thermohydraulic phenomena of top vented blowdown processes of initially supercritical carbon dioxide. The initial fluid conditions were chosen such that flashing occurred after saturation conditions were reached. The investigations were focused on pressure and temperature transients. It was observed that the pressure at which flashing occurred first depends mainly on the initial fluid conditions due to the almost isentropic change of state during the supercritical/subcooled blowdown. Furthermore, void fraction profiles along the axis of the vessel were measured by means of a gamma densitometer. The void fraction profile is influenced strongly by phase separation effects. Various stages of characteristic void profile were observed.

Dust explosions in totally enclosed interconnected vessel systems

Abstract: Some industrial dust-handling plant is designed so that, should an explosion occur, the overpressures can be totally contained. Such plant needs to be designed to withstand at least 10 bar overpressure. This may suffice for single compact vessels but experience indicates that in interconnected plant, explosion overpressures can be substantially increased. This effect is due to a process known as pressure-piling. There is no adequate guidance on how to take the effects of this process into account. This paper describes a project in which the behaviour of dust explosions in systems of linked enclosed vessels has been studied. Explosions of coal dust and toner dust have been produced in a number of linked systems using vessels ranging in size from 2 to 20 m3 and connected by 5 m lengths of pipe with diameters of 0.15 m, 0.25 m and 0.5 m. Pressure changes that occur when a dust explosion is ignited in one of the vessels and the flame transmits into the other have been measured. Pressure enhancement due to pressurepiling effects occurs in some systems, and pressures approaching 20 bar have been measured. The pipe diameter, vessel volumes and the volume ratio are important variables. These results are discussed and a simple method for the calculation of explosion pressure enhancement effects is described. Comparisons are made between the model predictions of the maximum explosion pressure and experimental measurements. The experiments have shown that, in some circumstances, there is a low probability of an explosion propagating along the pipe to produce an explosion in the second vessel. It appears that although the flame travels through the pipe and a jet flame enters the second vessel, it does not act as an effective ignition source. The wider the pipe diameter, the higher the frequency of an explosion in the second vessel.

Inerting of fine metallic powders

Abstract: Minimum explosible concentration (MEC) tests were carried out on mixtures of 50:50 AI Mg dust, AI dust, and 70:30 Mg Ca dust. MgO dust was added to these mixtures as an inertant. The results indicate that between 70 and 75% fine MgO dust is required to completely inert the 50:50 AI Mg dust, which is in the same range as the levels of rock dust needed for coal dust inerting. Use of a coarser MgO dust raises the quantity of MgO required to inert. Minimum oxygen concentration tests on the 50:50 AI Mg dust with added MgO correlated with the MEC results. Preparation of inert/metal dust mixtures is a novel method of decreasing the explosion hazard in manufacturing, transportation and for the end-user.

Dust explosions in pipes: A review

Abstract: In long pipes, the aerodynamic conditions are very favourable to (dust) flame acceleration and very severe explosions may result (as for instance in galleries of grain storage and handling facilities). The consequences of such explosions are likely to be disastrous if, at the end of the acceleration process, the flame reaches the ‘detonation’ regime for which overpressures of several tens of bars are possible. In this paper, it is primarily intended to present the actual state of knowledge concerning dust flame acceleration in pipes and detonations. In addition to this qualitative information, a (critical) review of some correlations linking the geometrical configuration and properties of the mixture to the ‘violence’ of dust explosions in pipes (maximum flame speed, maximum overpressure) is proposed. In conclusion an account of the means to prevent flame acceleration in pipes is given.

Hazard and risk potential of chemical handling at ports

Abstract: The techniques for hazard identification of cargo, ships and port installations is discussed. Hazardous events related to port installations are identified and effects of chemical releases on board ship, on sea and in port are discussed through cause-consequence analysis. Suggestions are provided with respect to hazard containment in cargo sheds.

Making the flare safe

Abstract: The paper presents a general review and checklist for many of the safety issues in flare design, specification and operation covering the obvious and not-so-obvious concerns. Common assumptions in flare specification are subjected to explanation and critique relative to their impact on safety. Subjects covered include: selection of height and location of elevated flares; flaring of toxic or noxious materials; flame stability as influenced by gas composition and operational procedures; flaring of unstable or hazardous materials; purging and the use of purge reduction devices; operational considerations to avoid problems; maintenance procedures to minimize risk.

An evaluation of validation procedures and test parameters for dense gas dispersion models

Abstract: This paper reports the evaluation of dispersion models with respect to their ability to predict the dispersion of continuous dense gas plumes over flat terrain. The exercise has been carried out in order to derive guidelines for statistical model evaluation exercises. Therefore, the models selected for the evaluation are simple: the Britter and McQuaid model and three variations of the Gaussian Plume Model. Two different evaluation procedures have been used: one using short time-averaged concentrations paired in time and space and another using observed maximum concentrations at certain distances together with a measure of the plume width. The performance numbers and ranking of the models depend substantially on the data sets used and the evaluation procedure and performance number selected. The two evaluation procedures have both advantages and disadvantages. An evaluation based on maximum concentration should not be performed without taking into account the plume dimensions. The evaluation using data paired in time and space suffers from the inability of the models and the data analysis techniques to match the predicted plume path with the actual plume path during the experiment. We suggest that two newly defined performance measures be used, the Mean Relative Bias and the Mean Relative Square Error, together with the well-known ‘Factor-of-2’ statistic in future statistical evaluation exercises. One should use at least two performance measures in an evaluation exercise in order to obtain a measure of ‘bias’ and ‘variance’. Furthermore, we advise that graphical presentations to obtain an understanding of the model behaviour be used.

Large scale characterization of the concentration field of supercritical jets of hydrogen and methane

Abstract: When an orifice or breach appears in the wall of a tank containing flammable gas under pressure, a jet is created which develops into an explosive cloud. Research has shown that the intensity of the explosion likely to take place in this cloud is then highly variable and depends on the cloud characteristics, such as the concentration of combustible material, the velocity field and turbulence. The experimental study developed at INERIS1 sought to characterise the clouds formed by supercritical jets of methane and hydrogen, and the overpressures resulting from ignition of the jets at different points. Only the work on the concentration fields will be reported here. The parameters determining the composition of the explosive cloud in the experiments carried out were: the gas used (methane or hydrogen), the vent orifice diameter (25, 50, 75, 100 or 150 mm) and the time t after the commencement of venting since the tank is of finite size and does not produce steady flow conditions. The volume of the tank (5 m3) and the pressure and temperature conditions - 40 bar and 288 K - inside it prior to the onset of venting were kept constant.

Model on-site emergency plan. Case study: Toxic gas release from an ammonia storage terminal

Abstract: Worldwide discussion of disaster management plans to cope with catastrophic injury to people and environmental destruction due to accidents in the chemical process industry was initiated after major chemically caused disasters at Seveso, Flixborough and Bhopal. An emergency plan is a formal written plan based on identified potential accidents together with their consequences. This plan describes how such accidents and their consequences should be handled both on- and off-site. The main aim of the plan is to limit the negative effects of an accident by being prepared with a plan and facilities ready to react without delay. The primary responsibility of the management of a hazardous chemical site is the prevention of accidents resulting in harm to human health, the environment or property. Thus, the plan for handling emergencies should describe all available help from the local professionals as well as governmental officials in order to supplement the company's own manpower. If a real emergency occurs and the personnel available do not have a well prepared written plan, the results could be far more serious than they would have been if a plan had been available. This paper provides an overview of release scenarios and affects area, response, organization, communications system, key personnel with specified responsibilities, work emergency procedures, emergency control centre, education and training, testing the plan/mock drill, performance review/observation and finalization.

Thermal hazard assessment and macrokinetics analysis of toluene mononitration in a batch reactor

Abstract: The thermal hazard assessment of toluene nitration in a batch reactor is implemented systematically using an isothermal reaction calorimeter in conjunction with micro-thermal calorimeters. The value of the heat of reaction is determined using calorimetric data, and the kinetic parameters for the desired reaction are derived from the isothermal self-heat rate vs time profiles. A series of safe operation limits are calculated. Results indicate that the desired reaction has a high potential to trigger a thermal explosion, caused by the decomposition of mononitrotoluene. By following these safe operation limits, suppression or elimination of the hazard potential is possible.

Effects of high expansion foam dispersed onto leaked LNG on the atmospheric diffusion of vaporized gas

Abstract: When LNG leaks from a storage tank, the LNG vapourizes vigorously above the adiabatic concrete floor inside the safety dike and the cryogenic methane diffuses in the atmosphere. It is well known that as the density of a vapourized gas drops, the atmospheric diffusion is enhanced due to buoyancy, and the concentration of vapourized gas along the ground decreases. The present paper is concerned with the ability of Hi-Ex (High Expansion Foam) to raise the temperature (decrease the density) of vapourized cryogenic gas, since the Hi-Ex system is usually applied as a fire protection system at LNG facilities. In the experiments, the liquid nitrogen pool was used to simulate LNG leakage, because the boiling point of liquid nitrogen is close to that for LNG. The small difference in the heat capacity of vapourized gas was taken into account in the evaluation of experimental results. The temperature variations with time of the vapourized gas which penetrated through the Hi-Ex layer were measured. Furthermore, the solidification of the Hi-Ex layer and the formation of flow passages in the Hi-Ex layer, and the change of evaporation rate of liquid after the dispersion of Hi-Ex onto it were examined in detail. Based on these experimental results, the heat balance among Hi-Ex, liquid, and vapourized gas was discussed, and the amount of Hi-Ex required to keep raising the temperature of vapourized cryogenic gas to that at which the density was almost the same as that of atmosphere was estimated.

Explosion venting technology

Abstract: Explosion venting technology describes one of the possible constructional protective measures against the effect of explosions. Thanks to the results of extensive explosion trials conducted in the last ten years, important gaps in our knowledge have been filled and new findings gained. Equations involving numerical values have been developed which represent an optimized mathematical matching of the innumerable experimental investigations, and which, as experience has shown, embrace the conditions of operational practice even for the most unfavourable cases. Details have also been provided on the hazards which can arise in outside areas due to flames and pressures. Calculation details are also given for the reaction forces caused by the venting process and which can lead to the equipment overturning.

The prediction of jet-fire dimensions

Abstract: This paper suggests a method of estimating the dimensions of gas jet fires in the buoyancy-dominated regime. The results should be of use to hazard analysts concerned with radiation and flame impingement. The length of a jet fire is determined by modifying the large-scale experimental data for propane of Hustad and Sonju (Progr. Astronaut. Aeronaut. 1985, 95) using a stoichiometric factor based on the method of Hawthorne et al. (‘Third Symp. Combus. Flame Explosion Phenomena’, 1949, p. 266). Agreement with the experimental results of Hustad and Sonju for methane is excellent. The jet fires are assumed to be cylindrical and the lateral dimension is estimated using the method offered by Marshall (IChemE Symposium Series No. 49, 1977, p. 99), based on momentum and dispersion considerations. The lateral dimension is over-estimated by comparison with experiment, but radiation calculations compare well.

Health and safety strategies in Europe

Abstract: This article outlines some of the findings of a European study set up to review the development of policy and strategy in health and safety in Europe between 1989 and 1995. The study received contributions from 13 member states of the European Union and focused on several indicators of health and safety strategies, including the extent and costs of occupational injuries and ill health, legislative arrangements, inspection, preventive services, arrangements for participative management of health and safety and insurance systems. Information concerning these indicators is reviewed against the background of economic developments in Europe during the same period. Because of the substantial difficulties in finding comparable data from different countries as well as reservations about the interpretation of such comparisons, the study sought to present a typology of systems and strategies rather than undertake a comparative review. In taking this approach the study demonstrates that there are a number of common trends apparent in the development of health and safety strategies as well as several economic, socio-political and legislative influences in common. At the same time, various models of insurance, participative management and preventive services in health and safety are illustrated, the development of all of which has been influenced by the economic trends of the 1990s. The study concludes that strategies in health and safety have undergone considerable change during the first half of the 1990s under the influence of the policies and instruments of the European Union. The effect of economic trends and the responses of business and Government serve to create a set of common influences in many European countries which have brought them closer together in terms of health and safety strategies. However, there are still very real differences between countries with regard to infrastructures and outcomes in health and safety. It is also observed that the implications for health and safety of many of the developments of the 1990s, such as the growth of the importance of SMEs in the economy, the reduction in public expenditure, flexible working and increases in precarious and illegal employment, as well as the ageing of the workforce and increased participation of women, are not adequately addressed by either the instruments of the European Union or the strategies of member states. In many respects the concept of ‘health and safety’ itself is a product of a previous era and does not lend itself easily to emerging concerns of a post-industrial society. This represents a major challenge to all participants in the development of strategies to promote the well being of people at work in Europe in the future.

Guidelines for Chemical Reactivity Evaluation and Application to Process Design

Abstract: Description: Drawn from international sources, this book provides principles and strategies for the evaluation of chemical reactions, and for using this information in process design and management. A useful resource for engineers who design, start–up, operate, and manage chemical and petrochemical plants, the book places special emphasis on the use of state–of–the–art technology in theory, testing methods, and applications in design and operations.