Safety management systems from Three Mile Island to Piper Alpha, a review in English and Dutch literature for the period 1979 to 1988

Objective: Which general management and safety models and theories trends influenced safety management in the period between Three Mile Island in 1979 and Piper Alpha in 1988? In which context did these developments took place and how did this influence Dutch safety domain? Method: The literature study was limited to original English and Dutch documents and articles in scientific and professional literature during the period studied. Results and conclusions: Models and theories of human errors, explaining occupational accidents were still popular in the professional literature. A system approach was introduced into mainstream safety science, starting in process safety, and subsequently moving into occupational safety. Accidents were thought to be the result of disturbances in a dynamic system, a socio-technical system, rather than just human error. Human errors were also perceived differently: they were no longer faults of people, but consequences of suboptimal interactions during process disturbances. In this period quality of safety research increased substantially, also in the Netherlands. Major disasters in the 1980s generated knowledge on process safety, and soon process safety outplaced developments in occupational safety, which had been leading before. Theories and models in this period had advanced sufficiently to explain disasters, but were still unable to predict probabilities and scenarios of future disasters. In the 1980s ‘latent errors’ appeared in safety literature, and in The Netherlands the concept of ‘impossible accidents' appeared. Safety management was strongly influenced by developments in quality management

Introduction of the concept of risk within safety science in The Netherlands focussing on the years 1970–1990

Serious incidents in the 1970s and continuous growth of factories producing and/or using hazardous substances formed the basis of a quantitative approach to risk. While discussions of risk were conducted in all industrialised countries they were particularly important in The Netherlands due to space limitations and short distances between industrial plants and residential areas. This article is part of a series covering the history of the safety science discipline (Swuste et al., 2015; Van Gulijk et al., 2009; Swuste et al., 2010). The concept risk entered the Dutch safety domain before the 1970s in relatively isolated case studies and in managing flood defences in The Netherlands. Since the 1970s these case studies paved the way for the development of mathematical models for quantitative risk analysis that were based on experience from nuclear power plants, the process industries and reliability engineering from operations research. ‘External safety’ was a focal point for these early developments in the process industries: adverse effects of dangerous goods outside the factory’s property boundaries. The models were documented in standardised textbooks for risk analysis in The Netherlands, the so-called ‘coloured books’. These works contributed to the development of the Seveso Directive. For internal safety (taking place within property boundaries) semi-quantitative approaches were developed simultaneously. The models for quantitative risk analysis were deemed reliable, but the acceptability of a quantified risk was another matter. Making decisions on risk relates to complex societal issues, such as ethics, stakeholder perception of risks, stakeholder involvement, and politics, all of which made the decision making process far from straightforward. With the introduction of the abstract concept of risk in the Dutch safety science domain, the question of risk perception became important in Dutch safety research. The concept risk and methods for quantitative risk analysis first entered into Dutch law in environmental risk regulations. It took a while for risk to be accepted by occupational safety experts, but just before the turn of the century ‘occupational risk inventory and evaluations’ or RI&E methods were introduced into Dutch occupational safety legislation. This finalised the paradigm shift to risk-based safetydecision making in the Dutch safety science domain. While methods for quantifying risk are now widely applied and accepted, the proper use of risk perception and risk in the political decision process are still being debated

Metal dusts explosion hazards and protection

\u3cp\u3eMany industrial processes handle, use, or produce metallic particles small enough to explode in air, thus posing severe explosion hazards. Finishing operations, for example, create very fine particles and have been involved in a growing number of accidents in recent years. New emerging processes, such as 3D printing, are being rapidly developed and directly use micrometric particles to create complete objects by welding layers of material together. Finely divided metals also enter into the composition of plastics, rubber, fibers, paints, coatings, inks, pesticides, detergents, and even drugs; additionally, they are used as catalysts for major industrial chemical reactions, and are even being explored as possible clean alternatives to fossil fuels. Metal dusts are of special concern due to their peculiar combustion properties, including their higher heat of combustion and pyrophoric nature,. As a result, metal dusts explosions are often much more devastating than explosions involving organic materials. Additionally, due to their high reactivity, many fine and most ultra-fine metal powders can burn in carbon dioxide, water vapor and even nitrogen. Whereas preventive measures may reduce explosion risks efficiently, they rarely are sufficient to eliminate explosions completely, especially when dealing with highly reactive metallic particles. Therefore explosion protection measures usually also need to be considered. The high energetic content of metal dusts poses new challenges to conventional explosion protection systems in terms of robustness and response time. This paper reviews the special hazards of metal dusts and presents the state-of-the-art in terms of explosion protection.\u3c/p\u3

Explosion hazards of aluminum finishing operations

\u3cp\u3eMetal dust deflagrations have become increasingly common in recent years. They are also more devastating than deflagrations involving organic materials, owing to metals' higher heat of combustion, rate of pressure rise, explosion pressure and flame temperature. Aluminum finishing operations offer a particularly significant hazard from the very small and reactive aluminum particles generated, and thus require high attention to details of operation and explosion safety management. This paper presents available statistics on metal dust explosions and studies the specific explosion hazards of aluminum finishing operations. The analysis of seven case studies shows that the proper design, monitoring and maintenance of dust collection systems are particularly important. Furthermore, the isolation of deflagrations occurring in dust collection systems, as well as good housekeeping practices in buildings, are critical safeguards to avoid the occurrence of catastrophic secondary explosions.\u3c/p\u3

Developments in the safety science domain, in the fields of general and safety management between 1970 and 1979, the year of the near disaster on Three Mile Island, a literature review

Objective: What influence has research conducted by general management schools and safety research had upon the causes of accidents and disasters in relation to the managing of safety between 1970 and 1979? Method: The study was confined to original articles and documents, written in English or Dutch from the period under consideration. For the Netherlands, the professional journal De Veiligheid (Safety) was consulted. Results and conclusions: Dominant management approaches started with (1) classical management starting from the 19th century incorporating as a main component scientific management from the early 20th century. The interwar period saw the rise of (2) behavioural management which was based on behaviourism, this was followed by (3) quantitative management from the Second World War onwards. After the war it was (4) modern management that became important. A company was seen as an open system, interacting with an external environment with external stakeholders. These management schools of thought were not exclusive, but existed side by side in the period under consideration. Early in the 20th century, it was the U.S. ‘Safety First’ movement that marked the starting point of this knowledge development in the sphere of safety managing, with cost reduction and production efficiency as the key drivers. Psychological models and metaphors were used to explain accidents resulting from ‘unsafe acts’. Safety was managed by training and targeting reckless workers, all in line with scientific management. Supported by behavioural management, this approach remained dominant for many years until long after World War II. Influenced by quantitative management, potential and actual disasters occurring after the war led to two approaches; loss prevention (up-scaling in the process industry) and reliability engineering (inherently dangerous processes in the aerospace and nuclear sectors). The distinction between process safety and occupational safety became clear after the war when the two evolved as relatively independent domains. In occupational safety in the 1970s human error was thought to be symptomatic of mismanagement. The term ‘safety management’ was introduced to scientific safety literature alongside concepts such as loosely and tightly coupled processes, organizational culture, disaster incubation and the notion of mechanisms blinding organizations to portents of disaster scenarios. Loss prevention remained technically oriented. Until 1979 there was no clear link with safety management. Reliability engineering that was based on systems theory did have such a connection with the MORT technique that served as a management audit. The Netherlands mainly followed Anglo-Saxon developments. In the late 1970s, following international safety symposia in The Hague and Delft, independent research finally began in the Netherlands

Igniter-induced hybrids in the 20-l sphere

Dust explosibility is traditionally described by two parameters, namely the maximum explosion pressure, Pmax, and the deflagration index, KSt, usually determined through testing in a closed, pressure-resistant spherical vessel, either 20 L or 1 m3 in volume. These parameters constitute key variables in the design of explosion protection systems, such as venting, suppression or isolation systems.\u3cbr/\u3e\u3cbr/\u3eThe potential for overdriving dust combustion with pyrotechnical igniters in the 20-l sphere has been recognized, discussed and analyzed for many years, notably in the determination of the minimum explosible and limiting oxygen concentrations, which has led to specific guidelines regarding the ignition source strength in ASTM standards.\u3cbr/\u3e\u3cbr/\u3eThe current paper presents new experimental evidence that the energy provided by pyrotechnical igniters may, in some instances, physically alter the dust being tested in the 20-l sphere. KSt values can be several times greater in the small vessel compared to those measured in the 1-m3 chamber. Further visual evidence is provided to show that high energy ignition can produce a turbulent flame region, possibly consisting of a hybrid mixture of flammable gas (or vapor) and dust, which can propagate faster than the corresponding pure dust. The experiments suggest that KSt values measured in the 20-l sphere may no longer be representative of a dust deflagration in a real process environment. We recommend additional tests in a 1-m3 chamber when a dust exhibits a low flash point, or when it's KSt is above 300 bar m/s in the 20-l sphere.\u3cbr/\u3