Catastrophic accidents/hazards

The rapid growth and expansion of the chemical industry has been accompanied by a spontaneous rise in human, material, and property losses because of fires, explosions, hazardous and toxic spills, equipment failures, other accidents, and business interruptions. Concern over the potential consequences of catastrophic accidents, particularly at chemical and petrochemical plants, has sparked interest at both the industrial and regulatory levels in obtaining a better understanding of the subject of this book Health, Safety, and Accident Management (HS AM). The writing of this book was undertaken, in part, as a result of this growing concern. 

The column s ability to weather foreseen and unforeseen difficulties is severely tested during startup and shutdown. Failure to recognize and eliminate pitfedls or hazards associated with these operations has caused catastrophic accidents, sometimes with injuries or loss of life damage to columns and their internals and/or prolonged periods of downtime. It is therefore imperative to recognize and eliminate (or at least minimize) the pitfalls associated with column startups and shutdowns. 

Introductory comments made in the previous chapter also extend to this chapter. Failure to recognize and eliminate operation pitfalls or hazards has caused catastrophic accidents, loss of life, iiyuries, damage to colmnns and their internals, and lengthy shutdown periods. 

Use of an integrated approach to hazard analysis will result in effectively identifying site and facility hazards, including chemical hazards and the hazards associated with the disposal of the hazardous chemicals. Analysis can begin at these levels by assessing chemicals present in quantities greater than the threshold quantities (TQ) found in 29 CFR 1910.119 and 40 CFR 355. These materials are generally analyzed from the process safety perspective, i.e., potential for a catastrophic accident with immediate consequences. 

Catastrophic accidents occur only rarely. This means that most employees will not have actually experienced such an event. Ironically, this lack of direct experience can be a particular problem for those conducting hazards analyses at those facilities that have excellent safety and environmental records. Managers and workers in such organizations do not necessarily become complacent but they may become a little too comfortable and satisfied with what they have achieved. They have trouble thinking the unthinkable. Conversely, on those plants that have witnessed a serious accident within the last few years there can be no denial that such events happen. For example. Process Hazards Analysis (PHA) leaders will often hear remarks from highly experienced team members such as Tve been here 14 years, and I ve never seen that happen... with the unspoken implication, ... therefore it cannot happen. It is the job of the PHA leader to crack that shell of unjustified self-satisfaction. 

A classic example of substitution concerns the use of hydrogen fluoride (HF) as an alkylation catalyst in oil refineries. The properties of HF that make it such an effective catalyst also make it a highly solvent and toxic chemical in the event of a release. An alternative alkylation catalyst is sulfuric acid. Although sulfuric acid is also a hazardous material, it cannot cause a catastrophic accident when released in the way that HF can. 

Another large handheld application segment is in positive material identification (PMI) where, similar to scrap sorting, the sample is identified as a specific alloy or material. PMI ensures that, for example, the repair of a crucial pipe in a hazardous material-containing process is only performed using the correct and certified material. After a catastrophic accident in a Texas refinery, PMI inspection of components carrying hazardous products was made mandatory. This mandate is easily accomplished on site using HH XRF instrumentation. 

Peroxide compounds are usually very reactive and flanunable. They have caused many catastrophic accidents around the world because of their reactive potential. Conventional methods to assess risk of such a reactive chemical have been done by experiments with precision machine such as DSC (differential scanning calorimeter), ARC (accelerating rate calorimeter), etc., but they need more finance, concentration and charge of danger. To overcome that, computer aided prediction method using group contribution method was used in this study. Some essential thermodynamic properties of chemicals were evaluated by this method, and then adiabatic temperature rise for each decomposition steps of peroxide compound were obtained, which can be a good index of the hazardousness of reaction. The result was approximate to other experimental and simulation data from references. 

Entry 3.6 again demonstrates how human error can lead to a catastrophic accident Of course, the best solution is to design the hazard out. In this case, you cannot take away the potential but have added numerous levels of redundant fail-safe mechanisms to prevent the mishap from occurring. Note that the ready tank already has a liquid-level indicator, but if it is only tied back to an alarm, it does not guarantee that the hazard will be prevented. It only means that the operator will be warned. The overfill hazard is too significant to be left to an alarm indication alone. 

The accuracy of absolute risk results depends on (1) whether all the significant contributors to risk have been analyzed, (2) the realism of the mathematical models used to predict failure characteristics and accident phenomena, and (3) the statistical uncertainty associated with the various input data. The achievable accuracy of absolute risk results is very dependent on the type of hazard being analyzed. In studies where the dominant risk contributors can be calibrated with ample historical data (e.g., the risk of an engine failure causing an airplane crash), the uncertainty can be reduced to a few percent. However, many authors of published studies and other expert practitioners have recognized that uncertainties can be greater than 1 to 2 orders of magnitude in studies whose major contributors are rare, catastrophic events. 

The employer investigates incidents that result in, or could result in, a catastrophic release of highly hazardous chemicals. An incident investigation is initiated as soon as possible, but before 48 hours following the incident. An incident investigation team is established to consist of one or more experts in the process involved, and accident investigation. The report prepared at the conclusion of the investigation includes at a minimum ... 

Environmentally hazardous projects are those where the risk of accidents is very high, which can result in a major and sometimes even catastrophic chemical pollution of the environment. Frequently, these disasters take casualties among the plant personnel, as well as among the nearby settlements population, which were the cases with the Chernobyl Nuclear Power Plant disaster in Ukraine, or with the pesticide plant accident in Bhopal, India. 

There are over 400 potentially hazardous industrial projects in Ukraine, 27 of which have the highest risk of accidents disasters with catastrophic consequences. During the last three years there have been registered 74 emergency situations of natural character, while there have been 123 records of man-caused emergencies, which is almost twice as many. This is a vivid illustration of the extremely poor technical condition of potentially hazardous installations. 

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