Hazard evaluation, application

Proper application of an event hazard evaluation teclmique also requires a sound knowledge of the types of hazards involved within die system. Tlie design engineer should develop a list sunuiiarizing die types of hazards diat warrant fiulher evaluation within die system. Tliis list could take die following hazards into account ... 

Adapted from H. Karranian, J.K. Rao and F.V. Hour, Application of Hazard Evaluation Teclmiqucs to tlic Design of Potential Hazardous Identification in Chcniical Processes, NlOSH, Cincinnati, Olrio, 1992. 

Adapted from H. Kavianian, J. Rao and G. Brown, "Application of Hazard Evaluation Tecluiiques to tlie Dangers of Potentially Hazardous Industrial Chemical Processes", NIOSH, Cincimiati, OH, 1992. 

The Seveso and Duphar accidents could have been avoided if proper containment systems had been used to contain the reactor releases. The proper application of fundamental engineering safety principles would have prevented the two accidents. First, by following proper procedures, the initiation steps would not have occurred. Second, by using proper hazard evaluation procedures, the hazards could have been identified and corrected before the accidents occurred. 

An overview of typical calorimetric techniques indicating sensitivities, principal application areas, and the usual data acquired is shown on Table 2.1. A brief summary of advantages and disadvantages of the various tests is also given. The column "principal applications" indicates only the major applications of the respective techniques. In any of the tests listed, it is possible to obtain additional data or to use the test equipment for completely different hazard evaluations once the techniques are fully understood and the tests are run by fully qualified technical personnel. Testing techniques are discussed later in Section 2.3 on Practical Testing. 

It is difficult to identify all of the possible events and their consequences in a complex chemical processing plant without the application of systematic procedures and proper management techniques. Several hazard evaluation procedures have been developed. Most of these procedures are described in other AIChE/CCPS publications such as Guidelines for Hazard Evaluation Procedures [2,3] and Guidelinesfor Quantitative Risk Analysis [4]. Other publications on hazard evaluation techniques include [246,247]. 

Seyler, R. J., "Applications of Pressure DTA (DSC) to Thermal Hazard Evaluation," Thermochimica Acta, 39 (1980). 

Some safety analysis techniques and their typical use are presented in Figure 3 as given by CCPS (1992). It can be seen that together these hazard evaluation methods cover well the needs of the life cycle of a process plant. However this is not a complete list but also some other methods are applicable as seen in Ch. 5. 

GENERAL References AICHE/CCI S Guidelines for Chemical Process Quantitative Risk Analysis, 2d ed., American Institute of Chemical Engineers, New York, 2000. AICHE/CCPS, Guidelines for Hazards Evaluation Procedures, 2d ed., American Institute of Chemical Engineers, New York, 1992. Crowl and Louver, Chemical Process Safety Fundamentals with Applications, 2d ed., Prentice-Hall, Englewood Cliffs, N.J., 2002. Mannan, Lees Loss Prevention in the Process Industries, 3d ed., Elsevier, Amsterdam. 

Other examples of inductive tools that have limited application in incident investigation include failure mode and effects analysis (FMEA), hazard and operability study (HAZOP), and event tree analysis (ETA). These are detailed in the CCPS book, Guidelines for Hazard Evaluation Procedures... 

If a recommendation asks for a change in the process, the action must undergo a formal process hazard analysis (PHA) study, such as a HAZOP or other methodology, before implementation. This systematic and formal approach identifies and evaluates hazards associated with the proposed revisions. The study may uncover failure scenarios, adverse consequences, and obscure relationships that are not immediately apparent. The CCPS publication Hazard Evaluation Procedures i is an excellent guide to selection and proper application of PHA methodologies. 

Process Hazard Analysis (PHA) can be defined as the application of a systematic method to a process design in order to identify potential hazards and operating problems. It determines the causes and consequences of abnormal process conditions that arise from equipment failure, human error or other events. The goal is to determine whether opportunities exist to reduce the risks of the toll s hazards and then to implement warranted action items. The AJChE CCPS guideline Guidelines for Hazard Evaluation Procedures, Second Edition with Worked Examples is a good resource for fully detailed approaches to process hazard analysis. It provides an introduction to hazard evaluation as well as guidance on ... 

We think it is valuable to consider the techniques and approaches used in the rocket propulsion areas since many of the concerns, and the devices and approaches developed to cope with these concerns, can be used by the chemical industry. This is perhaps particularly true when one considers hazard evaluation. The procedures developed in the propellant industry to assess explosive and fire hazards are directly applicable to the chemical process industry. In addition, some of the techniques developed for measuring the properties of liquid propellants, particularly at elevated temperatures and pressures (and frequently on materials which can decompose or even detonate), can be used in similar studies with actual commercial chemicals. 

Yih-Shing, D., Chang-Chia, H., Chen-Shan, K. and Shuh, W.Y. (1996) Applications of reaction calorimetry in reaction kinetics and thermal hazard evaluation. Thermochimica Acta, 285 (1), 67-79. 

The so-called Occupational Exposure Level (OEL) is a key parameter for people responsible for the safety issues in pharmaceutical and chemical industries. " The assessment and the application of the OEL are particularly important also for hazardous pharmaceuticals that are routinely handled within the pharmaceutical companies. There are different approaches to determine the OEL of a certain chemical and its relation to the handling/use of the substance. We are oriented to applying a tiered approach, which assesses all possible parameters that compose the hazard evaluation of a chemical substance. 

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