Catastrophic hazard

Economic, liability, public image, and opinion considerations are involved. Catastrophic hazards are less acceptable than smaller ones even if the absolute risk is identical. Voluntary risks are a way of life for most people, but there is minimal tolerance for involuntary risks, particularly if they are unknown or not understood. 

American Institute of Chemical Engineers (AlChE) to focus on engineering practices to help prevent and mitigate catastrophic hazardous chemical accidents. 

Wood-for-the-trees. Safety cases do not see the wood for the trees, giving equal attention and treatment to minor irrelevant hazards as to major catastrophic hazards, and failing to highlight, and concentrate on the principal hazards. 

Haddon-Cave then turned his attention to the safety case for the Nimrod MR2, which was intended to identify, assess and mitigate catastrophic hazards, which might occur to the aircraft. In plain language ... 

A catastrophic hazard is a hazard that has a Category I (Catastrophic) severity level, as defined by the hazard severity criteria in MIL-STD-882. 

A systematic project activity to ensure that a space payload intended for flight has sufficient structural integrity as to present no critical or catastrophic hazard. This activity also ensures quality of performance in the structural area for any payload. Central to the program is fracture control analysis, which includes the concepts of fail-safe and safe-life, defined as follows ... 

Example 9.1 A process involves the use of benzene as a liquid under pressure. The temperature can be varied over a range. Compare the fire and explosion hazards of operating with a liquid process inventory of 1000 kmol at 100 and 150°C based on the theoretical combustion energy resulting from catastrophic failure of the equipment. The normal boiling point of benzene is 80°C, the latent heat of vaporization is 31,000 kJ kmol the specific heat capacity is 150 kJkmoh °C , and the heat of combustion is 3.2 x 10 kJkmok. ... 

Risk-Based Inspection. Inspection programs developed using risk analysis methods are becoming increasingly popular (15,16) (see Hazard ANALYSIS AND RISK ASSESSMENT). In this approach, the frequency and type of in-service inspection (IS I) is determined by the probabiUstic risk assessment (PRA) of the inspection results. Here, the results might be a false acceptance of a part that will fail as well as the false rejection of a part that will not fail. Whether a plant or a consumer product, false acceptance of a defective part could lead to catastrophic failure and considerable cost. Also, the false rejection of parts may lead to unjustified, and sometimes exorbitant, costs of operation (2). Risk is defined as follows ... 

Catastrophic release Under OS HA PSM and EPA RMP, it means a major uncontrolled emission, fire, or explosion, involving one or more highly hazardous chemical substances (per OSHA) or regulated substances (per EPA) that presents serious danger to employees in the workplace (per OSHA) or imminent and substantial endangerment to public health and the environment (per EPA). 

Critical Equipment Equipment, instrumentation, controls, or systems whose malfunction or failure would likely result in a catastrophic release of highly hazardous chemicals, or whose proper operation is required to mitigate the consequences of such release. (Examples are most safety systems, such as area LEL monitors, fire protection systems such as deluge or underground systems, and key operational equipment usually handling high pressures or large volumes.)... 

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. 

Employers, at a minimum, must have an emergency action plan that will facilitate the prompt evacuation of employees when there is an unwanted release of a highly hazardous chemical. This means that the employer s plan will be activated by an alarm system to alert employees when to evacuate, and that employees who are physically impaired will have the necessary support and assistance to get them to a safe zone. The intent of these requirements is to alert and move employees quickly to a safe zone. The use of process control centers or buildings as safe areas is discouraged. Recent catastrophes indicate that lives are lost in these structures because of their location and because they are not necessarily designed to withstand over-pressures from shock waves resulting from explosions in the process area. 

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 ... 

Catastrophic Release - A major uncontrolled emission, of hazardous material that presents serious danger to workers or the public. 

The hazards of tliis arrangement arise from the possibility of a catastrophic release of the contents of the holdup tank into tlie atmosphere. A... 

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 regulation states The employer shall investigate each incident which results in, or could reasonably have resulted in, a catastrophic release of highly hazardous chemicals in to the workplace. ... 

Table 64.2 provides examples of hazardous chemicals that require investigation when a catastrophic release occurs or when one could have happened. These OSHA guidelines should be used in conjunction with site-specific procedures. For a complete listing of the reportable chemical used in your plant, refer to the site Hazardous Materials Policy and Procedure Manual. 

Chemicals are an essential part of modern commerce and cannot be eliminated without catastrophic consequences to public health, the environment and the economy. Limiting exposure to the most hazardous chemicals has been the focus of national and international groups for many years. The USEPA relies on the development and implementation of regulations such as the Clean Water Act, Toxics Uses Reduction Act (TURA) and the Clean Air Act (CAA) as regulatory pollution prevention tools. 

The only disadvantage to the use of hydrogen as a carrier gas Is the real or perceived explosion hazard from leaks within the column oven. Experience has shoim that the conditions required for a catastrophic explosion may never be achieved in practice.. However, commercially available gas sensors will automatically switch off the column oven and carrier gas flow at air-hydrogen mixtures well below the explosion threshold limit [143]. 

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