Technical context, safety

Safety or its derivatives used in a special or technical context. 

First section is related to the presentation of the context of the project. Second section aims describing basis of the framework currently developed. Third section presents an inventory of dimensions to be considered by the assessment of potential consequence of a change on socio technical system safety performance. Fourth part describes a module aiming to support assessment of consequences of change on system situation awareness performance. 

The various chemical substances present in a process plant may in favourable conditions react with each other or with air or water causing safety or technical problems. This chemical interaction is based on the chemical reactivity of each substance with other substances present in the plant. As a potential process hazard, the chemical reactivity of any substance should be considered in the following contexts ... 

Deichmann W (1972) The debate on DDT. Archives of Toxicology 29(1) 1-27 IPCS (2002) International Chemical Safety Card (ICSC) No. 0084, 0085, and 0086 (the recommendations on these cards also apply to technical xylene) prepared in the context of cooperation between the International Programme on Chemical Safety (IPCS) and the Commission of the European Communities (CEC). Date of peer review August 2002... 

Carcinogens in the Context of Council Directive 96/82/EC, Report by the Technical Working Group 8, Joint Research Centre and European Commission, ISIS, Institute for Systems Informatics and Safety, Seville, Spain, 2000. 

In this context only a small overview on explosible substances and their technical safety data shall be given in Table 3-12. Its main purpose is to provide a better feeling for magnitudes and the semantics introduced. 

If the Damkoehler number of isothermal semibatch processes is smaller than 10 the degree of accumulation becomes high. In such cases the reaction rate and thereby the heat production rate is not proportional to the feed rate alone. For such processes a synthesis optimization is recommended which in the last consequence will also benefit the overall process safety. As will be demonstrated in the context of the safety technical assessment of maloperations (c.f. Section 4.4), the reduction of the maximum accumulation is a very decisive factor. 

In the special case that the fuel is a dust, there are a number of substance properties which influence the affinity and course of the explosion. The most important substance property in this context is the particle size. In the sense of a safety technical rule of thumb it may be stated in simplified terms that every substance will become dust ex-plosible provided it is micronized sufficiently. This is mainly an effect which has to be attributed to the enormous rise in specific surface area accompanying the decreasing particle diameter. The other way round, the probability of dust explosibility becomes rather restricted if the mean particle diameter exceeds 500 pm. 

A systems engineering approach to safety starts with the basic assumption that some properties of systems, in this case safety, can only be treated adequately in the context of the social and technical system as a whole. A basic assumption of systems engineering is that optimization of individual components or subsystems will not in... 

The word safety has many different interpretations and is used in many different contexts. For those managing risk in the process industries, it is useful to distinguish between three types of safety technical safety, process safety, and occupational safety. There is considerable overlap between them, but the broad characteristics of each are as follows ... 

The internal norms may surface in internal procedures, technical project specifications, operating manuals and the like. These documents will in turn constitute relevant objects for state safety control state supervisory bodies evaluate the solutions and may react by requiring amendments to be made. More likely, the choices made by industry will be reviewed by the supervisory bodies in the context of the industry s applications for the various approvals, permits and licences needed to conduct the petroleum activities. 

Nevertheless in the context of the licensing procedure hardwired activation of safety functions is demanded in addition to PES activation, since it is still difficult to assess the reliability of computer programs. However, in [6] aspects are presented which have to be accounted for if electric/electronic/programmable electronic systems (E/E/PES) are used to realize safety functions. Below some general remarks are made following [7]. The corresponding mathematical and technical treatment is presented in Chap. 11. Since the requirements of [6] can be applied as well to other control systems than (E/E/PES) we speak in what follows of PCE equipment with the understanding that any of the above types of process control is meant. 

Safety and risk management research in healthcare has adopted as its dominant trend the systems oriented approach, modelled largely on previous research in safely critical industries such as aviation and nuclear power. The systems view entails that the focus is not primarily on the mechanisms of individual human error but on the factors that shape human performance (Rasmussen 1986 Reason 1993,1997). In an organisational context, such factors are, of course, those that are within the control of the organisation. For instance, it has been suggested that quahty and safety are affected not only by operators professional and technical competence and skills, but also by their attitudes to and perceptions of their job roles, their organisation and management (Helmreich and Merritt 1998). Such employee attitudes and views are important elements which shape safety cirlture - and its related notion safety climate . Indeed, survey studies have shown that staff attitudes are important indices of safety performance not only in human-machine system domains such as railway operations and constmction (e.g. Itoh and Andersen 1999 Itoh et al. 2004 Silva et al. 2004) but also in healthcare (e.g. Colla et al. 2005 Itoh and Andersen 2010). 

This chapter gives the context of this thesis by describing the participants and interactions in road traffic and the genesis of an accident. Accident statistics, safety development process, regulations, and current technical solutions highlight the objective of this thesis. 

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