Protective mitigating

The anode may be installed in conventional groundbeds or be laid in close proximity to the cathode, e.g. parallel to a pipeline route. The anode may be buried either directly in soil or in carbonaceous backfill. The major applications for this material are tank protection, internal protection, mitigation of poor current distribution and hot spot protection, i.e. to supplement conventional cathodic protection systems and provide increased levels of cathodic protection in areas that exhibit low levels of protection. 

The designer has the option to meet this objective in a variety of ways. For example, it can be accomplished through inherently safer design, providing fire protection mitigation systems, emergency response, or a combination of all three. 

In those cases where an engineering evaluation is used to establish life safety criteria, travel distance to an exit should at a minimum be determined by an evaluation of occupancy hazards, occupant loading, egress pathways and hazard protection/mitigation features of the warehouse building. 

Cathodic protection application. Hydrogen bubbles produced by cathodic protection mitigate the effect of imploding cavitation bubbles. Sacrifidal anodes, such as zinc or magnesium, can also be used. 

A great deal of experimental work has also been done to identify and quantify the ha2ards of explosive operations (30—40). The vulnerabiUty of stmctures and people to shock waves and fragment impact has been well estabUshed. This effort has also led to the design of protective stmctures superior to the conventional barricades which permit considerable reduction ia allowable safety distances. In addition, a variety of techniques have been developed to mitigate catastrophic detonations of explosives exposed to fire. 

Mitigation Reducing the risk of an accident event sequence by taking protective measures to reduce the likelihood of occurrence of the event, and/or reduce the magnitude of the event and/or minimize the exposure of people or property to the event. 

Process Safety A discipline that focuses on the prevention and mitigation of fires, explosions, and accidental chemical releases at process facilities. Excludes classic worker health and safety issues involving working surfaces, ladders, protective equipment, etc. 

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.)... 

Each alternative should be assessed in terms of the extent to which it mitigates short- and long-term potential exposure to any residual contamination and protects human health, both during and after implementation of the corrective measure. 

Protection from Fire Exposure and Pressure Relief Considerations - Pressure relief valves cannot protect a vessel that becomes locally overheated on an unwetted surface, although they do prevent the pressure from rising beyond the accumulation pressure of the valve. However, in such a case the vessel may be effectively protected against failure by either one of two methods for mitigating the effect of fire ... 

Mitigation The lessening of die risk of an accidental event. A sequence of action on the source in a preventive manner by reducing the likelihood of occurrence of the event, or in a protective manner by reducing the magnitude of the event and for the exposure of local persons or property. 

Tools are available to assist in comparing the risk associated with two or more different processes. For example, the first sheet of the Dow Fire and Explosion Index (FEI) (Dow, 1994b) ranks the safety characteristics of the process from a fire/explosion standpoint, without taking credit for protective and mitigation features. The Dow Chemical Exposure Index (CEI) (Dow, 1994a) and Id s Mond Index (ICI, 1985 Tyler, 1985) are other ranking tools. 

More inclusive is Table 3.3.1 -3 which is appropriate at depth into the analysis. The major headings in this table address major hazardous subject areas,. iccideni mitigation, protection and repair. I or example, under the first major heading, "Storage of Raw Materials, Products, Intermediates," listed are confinement measures, release nicclumi.sms (valves), procedures for safe operation and limitations that must be observed for safety. 

Forest fire Fire cannot propagate to the site because the site is cleared plant design and fire-protection provisions a adequate to mitigate the effects Seiche Included under external flooding... 

Mitigation System Resmnses Dikes and drainage. Hares, Fire protection systems (active and passive). Explosion vents. Toxic gas absorption... 

This book covers many aspects of DBA design, selection, specification, installadon, and maintenance. It explains how varions types of flame arresters differ, how they are constrncted, and how they work, ft also describes when a flame arrester is an effective solntion for mitigation of deflagrations and detonations, and other means of protection (e.g., oxidant concentration rednction) that may be nsed. It also briefly covers some aspects of dnst deflagration protection. 

Although iron pipes suffer from the same corrosion risk as steel pipelines, associated with the generation of a galvanic cell with a small anode and a large cathode, the risk is mitigated for iron pipelines because the electrical continuity is broken at every pipe joint. For this reason long-line currents are uncommon in iron lines and cathodic protection is rarely necessary. It also accounts for the ability to protect iron lines by the application of nonadherent polyethylene sleeving . 

The corrosion of reinforcing steel due to chloride contamination in concrete is an increasingly serious problem, and interest in cathodic protection as a means of mitigating corrosion on reinforced steel has become of some importance in recent years. 

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