Hazardous Materials Transportation Risk Assessment: State of the Practice (2013) / Chapter Skim
Currently Skimming:
Pages 76-87
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 76... ...
76 S e c t i o n 5 5.1 General Analysis 5.1.1 Types of Decisions The types of decisions presented in Section 4.1 show the range of issues that can benefit from either safety or security risk analyses (or both)
|
From page 77... ...
77 One example of how different analyses can use varied approaches to address the same element is in assessing environmental consequences. For some models, potential environmental exposure is estimated through counts of river and stream crossings or sizes of sensitive land areas within an impact distance.
|
From page 78... ...
78 can be quantified, they can be used with a more detailed analysis. Otherwise, a screening or qualitative level analysis can be performed.
|
From page 79... ...
79 tainer release probabilities to include qualifying factors, such as container speed at impact in the RCRMS model. The more holistic shipping industry models extend multi-dimensional probability factors even further to include, for example, the type of potential release (e.g., pool, BLEVE,12 jet fire, etc.)
|
From page 80... ...
80 deals with probability uncertainties through operational practices, such as using the most protective containers available for a given product, even if the container exceeds regulatory requirements. Threat Whereas safety risk methodologies most often determine the likelihood of an accident based on historical data to calculate frequency and/or probability, security risk models and methodologies tend to use qualitative data to define an event's likelihood as a function of threat and vulnerability.
|
From page 81... ...
81 ities and actions (RCRMS)
|
From page 82... ...
82 mined for each alternative and then the relative differences between these values is used in the decision making process. Risk scores are often thought of as being unitless.
|
From page 83... ...
83 riers because hazmat shipments by highway are perceived to be restricted to routes predetermined by governing agencies. Furthermore, there are no significant regulatory incentives to compare potential alternative routes for highway shipments as there are with rail.
|
From page 84... ...
84 Security Assessment Credibility and Transparency Several risk models rely on SMEs or involve classified or proprietary information or processes (black boxes) to identify, calculate, score, or compare risk components.
|
From page 85... ...
85 conducting risk assessments, which may result in inefficient risk-mitigation resource allocation and, with regard to hazmat risk consequences, negative effects on public safety. Public disclosure of intelligence reports or target-specific threat and vulnerability assessments will reduce their value by signaling that information to potential attackers.
|
From page 86... ...
86 nation of the three that are used by government agencies are usually considered sensitive information and classified, mostly due to the intelligence data used to calculate the threat component. As described earlier, disclosure of threat scores may cause an adversary to adapt their attack strategy, which could then invalidate the model's assumptions and results.
|
From page 87... ...
87 in underreporting accidents across modes could be used to obtain a more normalized comparison of accident rates. This would involve a research project to develop a methodology to estimate the levels of underreporting.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.