Hazard identification features

A hazard identification technique in which all known failure modes of components or features of a system are considered in turn, and undesired outcomes are noted... 

The word safety used to mean the older strategy of accident prevention through the use of hard hats, safety shoes, and a variety of rules and regulations. The main emphasis was on worker safety. Much more recently, safety has been replaced by loss prevention. This term includes hazard identification, technical evaluation, and the design of new engineering features to prevent loss. The subj ect of this text is loss prevention, but for convenience, the words safety and loss prevention will be used synonymously throughout. 

Hazard Identification. The first step is to determine whether a substance is mutagenic. For this purpose, inexpensive and sensitive short-term tests have been developed and are extensively used, nils report discusses the general features of these tests and proposes a specific mutagenicity screening program to detect potential mammalian mutagens. 

There exists a whole battery of methods for the identification of hazards in the literature.4 The hazard identification techniques suitable for various stages of a project are shown in Table 3.1. Among the techniques noted in Table 3.1 the most important method is safety audits, which cover the management system and specific technical features at site level and the management system at plant level. 

A good knowledge of statistical features of certain accidents, therefore, is the basic requirement to implement APS. In other words, major hazard identification must be performed. Statistical study on accident cases would be a powerful tool to meet this requirement. For this purpose, we collected all the related coal gas explosion accidents that analyzed in China s Coal Mine Accident and Expert Comments Set from the years of 1950-2000 (Jiefan Wang Wenjun Li 2001). The research focused on statistical features such as space, time and gas accumulation reasons, gas grade, ignition sources, accidents categories, and accident economic loss. Through this research, certain model and representativeness results will be drawn. 

Manufacturers typically provide a manual with their machines. The manuals cover hazard identification, safeguards, proper operation and maintenance. Good manuals use imperative writing style that teUs users what to do. Manuals that simply describe the features of a machine are not as helpful and effective. Those who buy machines should keep the manuals so the information is available for reference and training. Some major distributors and sellers of machines and tools also offer safety information and guides. 

Hazard identification and risk assessment Depending on the features selected and the environmental conditions assumed for each derived product, the way in which the argument considers the risk posed by hazards could vary (ArgSysHz). Not all hazards may be relevant to all product configurations. Also, the risk assessment results for each applicable hazard may vary due to some variable external or system features. Further, the risk tolerability criteria may vary across products if these products are deployed in different environments with different certification requirements, e.g. civil vs. military applications. 

Since hazard identification is the foundation of future courses of action, the selection of a proper identification technique is essential. The following are the features expected of hazard identification techniques ... 

After consideration of these questions, detailed mechanical design drawings will be made of all of the BOP items that need to be sourced or fabricated. A basic electrical line diagram will be drawn up that shows how the various electrical and control items link together, with safety features included. A hazard identification (hazid) and/or hazard and operability study (hazop) or similar safety analysis will also be carried out. These considerations are outside the scope of this book but it is hoped that the reader would have gained enough understanding of the systems to be able to inquire further. 

Failure Mode and Effect Analysis, FMEA, is a hazard identification technique in which all known fiiilure modes of conqwnents or features of a q stem are considered in turn and undesired outcomes are noted. The system has had limited use in the chemical industry in Europe as it is tedious and does not readily identify conqxrsition chan. Data for reliabilify studies can be very difficult to obtain. 

The design of most process plants relies on redundant safety features or layers of protection, such that multiple layers must fail before a serious incident occurs. Barrier analysis ) (also called Hazard-Barrier-Target Analysis, HBTA) can assist the identification of causal factors by identifying which safety feature(s) failed to function as desired and allowed the sequence of events to occur. These safety features or barriers are anything that is used to protect a system or person from a hazard including both physical and administrative layers of protection. The concepts of the hazard-barrier-target theory of incident causation are encompassed in this tool. (See Chapter 3.)... 

The related theory about extenics is founded by the Chinese scholars Cai wen to solve the problem of subjective and objective contradictions in 1983 (Cai, 1983), it bases on the matter-element theory and extension set theory and does research on the influence degree of the described problems about quantity and quality , so as to completely know the system features (Guo et al., 2009). Due to the complexity production conditions of underground working face, there are a variety of factors that affect gas emission, how to quickly and accurately judge the reasons that why the gas emission is abnormal is an important task of gas early-warning, the extension theory can calculate the abnormal gas emission level by using the normalized correlation function. Under the condition of correct identification of gas hazard in coal mine. 

Figure 12.1 shows the interactions between development and operations. At the end of the development process, the safety constraints, the results of the hazard analyses, as well as documentation of the safety-related design features and design rationale, should be passed on to those responsible for the maintenance and evolution of the system. This information forms the baseline for safe operations. For example, the identification of safety-critical items in the hazard analysis should be used as input to the maintenance process for prioritization of effort. 

A formal hazard analysis of the anticipated operations was conducted using Preliminary Hazard Assessment (PHA) and Failure Modes and Effects Analysis (FMEA) techniques to evaluate potential hazards associated with processing operations, waste handling and storage, quality control activities, and maintenance. This process included the identification of various features to control or mitigate the identified hazards. Based on the hazard analysis, a more limited set of accident scenarios was selected for quantitative evaiuation, which bound the risks to the public. These scenarios included radioactive material spills and fires and considered the effects of equipment failure, human error, and the potential effects of natural phenomena and other external events. The hazard analysis process led to the selection of eight design basis accidents (DBA s), which are summarized in Table E.4-1. 

A systematic process is used to evaiuate each of the hazards, potential consequences, and mitigative features that have been identified in the hazard anaiysis, using PHA and FMEA techniques. The potential mitigation which may be available in normal, abnormal, and accident conditions is then examined and an assessment made as to its contribution to public and to worker safety. This process is depicted in Figure 3.3-1, and ieads to the identification of Safety SSC s and safety benefits which contribute to public or worker safety but which do not meet the criteria for identification as Safety SSCs. This identification is further reflected In HCF TSR s for Safety SSC s and in HCF operating or administrative procedures. 

The defense in depth philosophy is embodied in all HCF operations through safety features that prevent the uncontrolled release of hazardous levels of radioactive or toxic material in normal and abnormal conditions. Only a limited set of these features meet the criteria of providing a major contribution to preventing or mitigating an uncontrolled release, leading to identification as SSSSC s. 

Description of subsurface conditions, including any information on groundwater, from study of geological maps and memoirs, previous site investigation reports and any features or outcrops observed during site walkover. Identification of possible geological hazards, e.g. buried channels in alluvium, solution holes in chalk and limestone, swelling/shrinkable clays... 

In this section, the development of a LC lAMS is described. Section 5.2.2 summarizes the MS instrumentation for the alkali-metal ion/molecule association reaction a quadmpole mass spectrometer (QMS), combined with the Li+ ion attachment ionization source (model L-241G-I A, Canon Anelva Corp, Tokyo). The performance and response of this equipment and unique features are also presented (Sect. 5.2.3). Finally, the interesting applications are reviewed. There are some interesting and unusual applications of lAMS that broaden MS (i) intermediary free radical species detection, in the gas phase reactions, diagnosis of plasma and diamond film chemical vapor deposition (CVD), (ii) detection of atmospheric and interstellar species, (iii) detection of environmentally important species, and (iv) identification of unfamiliar or unstable species. Restriction of Hazardous Substances Detectives (RoHS) is also discussed. 

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