Inherently hazard elimination

Inherent hazards, eliminated by design, make the AP600 inherently safe with respect to these hazards. The AP600 has some inherently safe characteristics -- the negative reactivity coeffident at all times which halts the chain reaction in the event of an expected power increase, the large water inventory, and the provision to limit any release from the containment by placing... 

After the inherent hazards are reduced, layers of protection are frequently used to protect the receptors of the hazard—the public, the environment, workers, other processes, or the process itself (Figure 1.1). In the strictest sense, one could argue that the definition of inherently safer applies only to elimination or reduction of the hazard. In the broad sense, the strength of a layer of protection can be improved by features that are permanent and inseparable from that layer. Thus, layers of protection can be classified into three categories, listed in decreasing order of reliability passive, active, and procedural. A passive layer of protection can be described as inherently safer than an active... 

Alternative 3 eliminates the risk of exposure at the site to the same levels as Alternatives 4 and 5 in the short term however, it relies solely on a cap for controlling the waste remaining in Area 1. Although capping is an effective and accepted approach for reducing risk from direct contact with wastes, it is less reliable in the long term than treatment, because the inherent hazard of the lead would remain. 

In liquid phase aerobic oxidation of p-xylene in acetic acid to terephthalic acid, it is important to eliminate the inherent hazards of this fuel-air mixture. Effects of temperature, pressure and presence of steam on the explosive limits of the mixture have been studied. 

Preliminary Hazard Analysis. The next step in the process is the development of a PHA. This analysis is the core of the FSS program and as such is vital in eliminating or reducing the inherent hazards associated with this laboratory operation. The PHA is used to further analyze the data identified in the PHL. This enhances the hazard control data base and provides specific recommended corrective action for the resolution of hazardous conditions. A combination of the informational sources used in the PHL development and any additional design information should be used in PHA development. 

In the United States, it is deemed unacceptable to dilute a waste that poses a high-hazard for the purpose of reducing the hazard, including doing so by combining wastes of different hazard, unless such combination eliminates an inherently hazardous characteristic e.g., ignitability, corrosivity). 

RSPs are designed to eliminate the possibility of UXO detonation, typically through fuze removal or disablement. Since performing an RSP is inherently hazardous, preparations should be made in advance for a high-order detonation in case the RSP is not successful. EOD technicians frequently perform RSPs remotely to ensure their safety in case of accidental detonation. Since performing RSPs is time consuming and costly, the process should be used only when BIP or movement of the UXO for disposal in a prepared disposal area is not possible. 

Inherent. Reducing or eliminating hazards by using less hazardous materials and process conditions. This philosophy of inherent hazard reduction is currently being advocated since it is the surest method for achieving safe working conditions. 

Inherently safer plant uses basic design measures to achieve hazard elimination, prevention and reduction. The classic definition of an inherently safe plant or activity is one that cannot under any circumstances cause harm to people or the environment. This may be because ... 

The primary philosophy is to follow the principles of inherent safety. This implies a systematic effort to apply the principles of hazard elimination, minimization/ intensification, hazard substitution, moderation/attenuation, and simplification. However, additional controls will still be required to control a hazardous situation, prevent escalation, and mitigate the risk to people, to the environment, asset, and reputation. Preferably, these safeguards will be passive- or active-engineered controls rather than administrative controls (i.e., dependent on direct human intervention). 

Recommendation 3 One way to eliminate the risk of this occurrence is to automate the system so that, once the operator lowers the crane into the tank and the crane stops at the predetermined level, the crane will automatically begin to rise out of the vapor cloud after the 10-minute degreasing operation. However, while such a system would eliminate the risk, it would, of course, be very expensive to install and maintain. There are also inherent hazards that exist whenever any equipment starts automatically. As an alternative, installation of a simple automatic timing device in the operator s console that will sound an alarm after the 10-minute period has elapsed will alert the operator to remove the parts from the tank. This alternative recommendation would not totally eliminate the risk, but it will reduce, or control it to a much lower and therefore acceptable level. 

In addition, the presence of many other different types of potentially hazardous industrial ehemicals was discovered across anumber of the products tested. As inherently hazardous substances, any use of NPEs, phthalates, or azo dyes that can release cancer-causing amines, is imacceptable. As global players, fashion brands have the opportunity to work on global solutions to eliminate the use of hazardous substances throughout their product lines, and to drive a change in practices throughout their supply chains. 

Accidents and mishaps are the direct result of hazards that have been actuated. (Note Accidents and mishaps are synonymous terms, and mishap has become the preferred term in system safety.) Mishaps happen because systems contain many inherent hazard sources (e.g., gasoline in an automobile), which cannot be eliminated since they are necessary for the objectives of the system. As systems increase in complexity, size, and technology, the inadvertent creation of system hazards is a natural consequence. Unless these hazards are controlled through design safety mechanisms, they will ultimately result in mishaps. 

The PtD focus is to achieve workplace safety by levels 1-3, thereby avoiding reliance on levels 4-6. While the optimal approach is complete elimination of a hazard, there may be limitations because water industry facilities have some inherent hazards that cannot be completely designed out. Therefore the PtD goal is to use the hierarchy of controls to modify the design within practicable limits, reducing the hazards as low as is reasonably possible. 

JHA is used to assess the existing and potential hazards of a job, understanding the consequences of risk, and act as an aid in helping identify, eliminate, or control hazards. JHA is a tool used to focus and break down a specific job, define its required steps and tasks and identify its inherent hazards and risks. JHA focuses on the relationship between ... 

By converting the plant to natural gas, we displace the use of coal and eliminate the hazardous air emissions associated with its combustion — but we need to invest into a new technology. The new process is generically referred to as cleaner production, simply because it is inherently cleaner or less polluting, and the technology is referred to as green technology. ... 

Hazards can be reduced or eliminated by changing the materials, chemistry, and process variables such that the reduced hazard is characteristic of the new conditions. The process with reduced hazards is described as inherently safer. This terminology recognizes there is no chemical process that is without risk, but all chemical processes can be made safer by applying inherently safer concepts. This book occasionally uses the term inherent safety this does not mean absolute safety. 

What do we mean when we speak of an inherently safer chemical process Inherent has been defined as existing in something as a permanent and inseparable element, quality, or attribute (American College Dictionary, 1967). A chemical manufacturing process is inherently safer if it reduces or eliminates the hazards associated with materials and operations used in the process, and this reduction or elimination is permanent and inseparable. To appreciate this definition fully, it is essential to understand the precise meaning of the word hazard. A hazard is defined as a physical or chemical characteristic that has the potential for causing harm to people, the environment, or property (adapted from CCPS, 1992). The key to this definition is that the hazard is intrinsic to the material, or to its conditions of storage or use. Some specific examples of hazards include ... 

These hazards cannot be changed—they are basic properties of the materials and the conditions of usage. The inherently safer approach is to reduce the hazard by reducing the quantity of hazardous material or energy, or by completely eliminating the hazardous agent. 

For these reasons, the inherently safer approach should be an essential aspect of any safety program. If the hazards can be eliminated or reduced, the extensive layers of protection to control those hazards will not be required. 

Inherently safer processes provide an opportunity to reduce or eliminate many of these long term economic costs. These benefits will not be realized unless we recognize and fully account for the long term costs associated with hazardous materials and processes. 

Note that we refer to a process as inherently safer, when compared to some other alternative, but not as "inherently safe. All materials and processes have hazards, and it is not realistic or practical to propose that we can eliminate all of them. In many cases we can identify material and process alternatives which clearly reduce hazards, and we can consider those alternatives to be inherently safer. 

Inherently safer design is a fundamentally different way of thinking about the design of chemical processes and plants. It focuses on the elimination or reduction of the hazards, rather than on management and control. This approach should result in safer and more robust processes, and it is likely that these inherently safer processes will also be more economical in the long run (Kletz, 1984, 1991b). 

Inherent—Eliminating the hazard by using materials and process conditions which are nonhazardous e.g., substituting water for a flammable solvent. 

The combination of several unit operations into a single piece of equipment can eliminate equipment and simplify a process. There may be inherent safety conflicts resulting from this strategy (see Section 2.4). Combining a number of process operations into a single device increases the complexity of that device, but it also reduces the number of vessels or other pieces of equipment required for the process. Careful evaluation of the options with respect to all hazards is necessary to select the inherently safer overall option. 

Innovative chemical synthesis procedures have been proposed as offering potential for economical and environmentally friendly routes to a variety of chemicals. These novel chemical reactions also offer potential for increasing the inherent safety of processes by eliminating hazardous materials, eliminating chemical intermediates, or allowing... 

The identification of hazards includes both a search for those hazards reduced or eliminated by inherently safer design, and a search for hazards controlled by instmmentation and administrative procedures. 

The ultimate goal of inherently safer design is elimination of all hazards with no need for controls. However, some control systems are always required. The working logic of a specific control system can make it inherently safer than other alternatives. 

During process hazard reviews, evaluate each safety critical device or procedure to see if the device or procedure can be eliminated by applying inherently safer principles. Consider the existing plant, the next plant, and the plant after next. 

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