Hazard Ranking Methods

The Superfund Amendments and Reauthorization Act (SARA) provides guidelines to improve Superfund enforcement methods and criteria. SARA also refines the Hazardous Rankings System, and by OSTRI prioritizes remediation activities. Rules and regulations under the Superfund and its SARA amendment are accessible at http //www.epa.gov/superfund/action/index.htm. 

A number of qualitative hazard identification methods are available to the risk analyst. Some of the more popular ones are discussed here. Further detailed information can be found in CCPS (1992). These methods become more powerful tools if they are coupled with the matrix-based risk-ranking scheme previously described. 

The answer is to correlate the hazard severity and probability or likelihood and create a ranking scheme. Different safety analysis techniques handle this question in different ways. The hazard analysis standard is Mil-Std-882 System Safety Program Requirements (U.S. Department of Defense, 2012). The ranking method is a very easy, three-step process ... 

Risk matrices provide a framework for an explicit examination of the frequency and consequences of hazards. The method may be used to rank the hazards in order of significance, screen out insignificant ones, or evaluate the need for risk reduction of each hazard. A risk matrix separates the dimensions of probability (POP) and consequence (COF) into typically three to six categories (A to E in Fig. 12.9). 

List the types of methods used to report hazards. Rank these methods in the order you believe is most effective and be able to discuss why you ranked them in this order. 

The system provides a method of ranking one risk relative to another. It is not intended to define a particular containment system as safe or unsafe but provides a way of comparing toxic hazards. It deals with acute, not chronic, releases. The procedure focuses on the... 

Dow Fire and Explosion Index (F EI) A method (developed by Dow Chemieal Company) for ranking the relative fire and explosion risk assoeiated with a proeess. Analysts ealeulate various hazard and explosion indexes using material eharaeteristies and proeess data. 

The amount and type of hazards will determine the performance standard specified in site-specific control plans. This includes the content, detail, and formality of review. The approval of the plans is based on risk and hazard potential. Using the hazard-based approach, levels of risk or methods to rank risk (degree) are standardized. 

The effectiveness of incineration has most commonly been estimated from the heating value of the fuel, a parameter that has little to do with the rate or mechanism of destraction. Alternative ways to assess the effectiveness of incineration destraction of various constituents of a hazardous waste stream have been proposed, such as assessment methods based on the kinetics of thermal decomposition of the constituents or on the susceptibility of individual constituents to free-radical attack. Laboratory studies of waste incineration have demonstrated that no single ranking procedure is appropriate for all incinerator conditions. For example, acceptably low levels of some test compounds, such as methylene chloride, have proved difficult to achieve because these compounds are formed in the flame from other chemical species. 

Chemical Exposure Index (CEI) (Chemical Exposure Index, 1994 Mannan, 2005, pp. 8/22-8/26.) The CEI provides a method of rating the relative potential of acute health hazard to people from possible chemical release incidents. It may be used for prioritizing initial process hazard analysis and establishing the degree of further analysis needed. The CEI also may be used as part of the site review process. The system provides a method of ranking one risk relative to another. It is not intended to define a particular containment system as safe or unsafe, but provides a way of comparing toxic hazards. It deals with acute, not chronic, releases. Flammability and explosion hazards are not included in this index. To develop a CEI, information needs include... 

Relative Ranking Techniques (DOW and MOND Hazard Indices) - This method assigns relative penalites and awards points for hazards and protection measures respectivesly in a checklist accounting form. The penalties and award points are combined into an index which is an indication of the relative ranking of the plant risk. 

The current situation with regard to risk assessment in the use of a wide range of different types of flame retardant is reviewed with respect to EEC council regulation No.793/93. The countries responsible for risk assessment on particular materials are listed and tonnages of materials used are noted. Three methods of prioritisation are used based on quantity used, environmental hazard potential and environmental risk ranking. 6 refs. 

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