Systematic Search for Hazards

In this section, a selection of commonly used hazard identification techniques is presented. These techniques can be used in the fine chemicals and pharmaceutical industries. The methods presented here are designed to provide a systematic search for hazards with the final objective of providing a comprehensive analysis. 

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Systematic searches for hazard, assessment of risk, and identification of possible remediation are the basic steps of risk analysis methods reviewed in this chapter. 

Key phrases systematic search for hazards, preliminary hazard analysis, risk reduction decisions. 

The systematic search for all chemical reactivity hazards, beyond the information gained from the sources listed in Section 4.2, should begin with a literature survey of the chemicals to be used and the type of processing, if any, that will be employed. The literature survey might turn up quantitative hazard data or previous incidents. Other information that will be useful later, such as standard practices or model prevention programs, may also be uncovered. 

The next part of a systematic search for chemical reactivity hazards is gaining an understanding of the inherent chemical energy present and conditions under which it can be released. 

HAZOP stands for Hazard and Operability Studies, a set of formal hazard identification and elimination procedures designed to identify hazards to people, processes, plants, and the environment. The techniques aim to stimulate the imagination of designers and operations people in a systematic way so they can identify potential hazards. In effect, HAZOP studies assume that there will be mistakes, and provide a systematic search for these mistakes. In some European countries, HAZOP studies are mandatory and attended by observers from regulatory authorities to ensure that the studies are carried out correctly. The examination of accidents52 during 1988 at a large U.S. chemical company revealed that the accidents could be classified as follows ... 

Identify risks/hazards/events that affect achievement of an entity s objectives. This step involves the systematic search for events and associated scenarios. The identification step is of critical importance as only identified events can be dealt with. Numerous techniques have been developed for the identification of events and associated scenarios. The different frameworks leave considerable room for the selection of appropriate methods (e.g. checklists, HAZOP, FMEA). 

Systematic search for specific chemical/physical hazards against plant preliminary flow sheet or block diagram. 

The HAZOP method is a systematic search for specific operational hazards against plant firm (not frozen) P 1 D or Eng Line Diagrams. 

Use of the Preliminary Screening Method of Chapter 3, along with the chemical reactivity data collected so far (Section 4.2), should begin to give at least a qualitative idea of the chemical reactivity hazards that may be present in an actual or proposed facility. However, the absence of particular information does not imply that no hazards exist. For this reason, a systematic search to attempt to identify all chemical reactivity hazards, in the context of how materials will be used in the actual process, is the next step in effectively managing chemical reactivity hazards. If a particular hazard is not recognized, it is not likely to be adequately controlled. 

A systems hazards analysis (SHA) is a systematic and comprehensive search for and evaluation of all significant failure modes of facility systems components that can be identified by an experienced team. The hazards assessment often includes failure modes and effects analysis, fault tree analysis, event tree analysis, and hazards and operability studies. Generally, the SHA does not include external factors (e.g., natural disasters) or an integrated assessment of systems interactions. However, the tools of SHA are valuable for examining the causes and the effects of chemical events. They provide the basis for the integrated analysis known as quantitative risk assessment. For an example SHA see the TOCDF Functional Analysis Workbook (U.S. Army, 1993-1995). 

MMD Lack of information flow and misperceptions with incubation period Make systematic efforts to collect information about hazards and build culture for active search for signals of danger... 

Milne, M., Hazard, G.F.Jr., "A Systematic Analysis of Substructure Search Questions for the Chemotherapy Program of the National Cancer Institute, 164th National Meeting of the American Chemical Society, August, 1972. 

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