System hazard analysis preparing

The ETBA is an analytical technique that can be of great assistance in preparation of the preliminary hazard list (PHL). It can also be quite useful in the development of a preliminary hazard analysis (PHA), subsystem hazard analysis (SSHA), or the more general system hazard analysis (SHA). The ETBA can also be used, depending on the specific system under consideration, in the development of the operating and support hazard analysis (O SHA), and, of course, during the MORT process from which the ETBA evolved. 

Conduct a thorough Process Hazards Analysis (PHA) for the following areas raw material storage, raw material feed systems, catalyst preparation, and catalyst storage. The PHA leader must he on the approved corporate list. Ensure the following scenarios are considered ... 

Ericson, C.A., 2005. Hazards Analysis Techniques for System Safety. Wiley-Interscience. Evans, R.A., 05 January 1976. Engineering Design Handbook, Design for Fault Tree Handbook with Aerospace Applications, Version 1.1, Prepared for NASA Office of Safety and Mission Assurance. NASA Headquarters, Washington, DC. 20546. August 2002. Hixenbaugh, A.F., 1968. Fault Tree for Safety. The Boeing Company, Seattle, WA. D6-53604. Retrieved 2014-05-18. 

In 1985, the American Institute of Chemical Engineers (AIChE) initiated a project to produce the Guidelines for Hazard Evaluation Procedures. This document, prepared by Battelle, includes many system safety analysis tools. Even though frequently identified as hazard and operability (HazOp) programs, the methods being developed by the petrochemical industry to use preliminary hazard analyses, fault trees, failure modes, effects, and criticality analyses, as well as similar techniques to identify, analyze, and control risks systematically, look very much like system safety efforts tailored for the petrochemical industry (Goldwaite 1985). 

Common hazard analysis tasks include the preparation of a preliminary hazard analysis, systems and subsystem hazard analyses, and an operating hazard analysis. These tasks also aid in the hazard control and hazard reduction effort. 

The preliminary hazard analysis (PHA) is an initial look at the entire system. A PHL, if available, is expanded by adding new hazards that may be identified as more project information is developed, as well as more information about each hazard. If a PHL has not been prepared, the PHA serves as the primary hazard identification tool as well as the initial hazard analysis. The methods used for conducting a PHA are basically the same as for a PHL, even though occasionally more advanced techniques may be appropriate. 

The MORT tools and techniques can be helpful in preparing a safety analysis report (SAR), the upstream safety product most frequently required for new DOE programs, but the more common system safety products (system safety program plan, preliminary hazard analysis, system/subsystem hazard analysis, operating hazard analysis) are not a dominant part of the MORT program and are seldom even referenced in System Safety Development Center (SSDC) documents. 

Preliminary drawings or sketches may be adequate to prepare a preliminary hazard list. More detailed drawings are required for a preliminary hazard analysis, and even more detail is required for subsystem and system hazard analyses. Analytical trees, copies of maintenance and operating procedures (if available), and site maps may also be helpful. 

Safety analysis report (SAR) A document prepared to document the results of a hazard analysis performed on a system, subsystem or operation. Hie specific minimum data elements for an SAR will be defined by data deliverable requirements for the program or project (NSTS 22254). 

The Preliminary Hazard Analysis (PHA) is an analysis of the generic hazard groups present in a system, their evaluation, and recommendations for control (TAI 1989). The PHA is usually the first attempt in the system safety process to identify and categorize hazards or potential hazards associated with the operation of a proposed system, process, or procedure. In many instances, however, the PHA may be preceded with the preparation of aPreliminary Hazard List (PHL). The identification of hazards on a PHL can occur through the use of a variety of methods such as but not limited to... 

For example, any sound analysis, including risk analysis, should be based on a series of observations and measurements. The first stage of this activity, before the hazard identification can be carried out, should be to define a system to be analysed, including the definition of the scope and context of the analysis, and the development of some form of system description. This preparation should also support the identification of the experience and expertise of the participants of the hazard identification process. Yet none of the guidelines provide any support in this area. 

All safety activities refer to an item . An item in terms of ISO 26262 is defined as a system or array of systems to implement a function at the vehicle level, to which ISO 26262 is applied . The Item Definition marks the scope of the Safety Considerations on an overview level and is the starting point of all furflier safety activities. It is, in particular, a necessary preparation for the Hazard Analysis and Risk Assessment (HARA), because in order to identify malfunctions that may lead to scenarios that bear the risk of an accident (called hazards), the interfaces of the investigated system to its environment must be known, as well as the specified behavior at these interfaces. Deviations from this specified behavior constitute the item s failures, a subset of these constituting the hazardous failures. As explained above, CMSs are well-suited to be regarded as an item according to the definition in ISO 26262. So the Item Definition usually depicts the entire CMS with camera(s), processing unit(s) and display(s). 

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