Quantitative risk assessment frequency evaluation

Recommendation 4. The quantitative risk assessment (QRA) for each chemical demilitarization site should be iterative. Actual chemical events should be used routinely to test the completeness of the QRA, which should be routinely utilized to hypothesize the frequency and consequences of chemical events. The Program Manager for Chemical Demilitarization and the U.S. Army Soldier and Biological Chemical Command should use the QRAs to evaluate measures to control future chemical events. The Army should also consider using QRAs to examine scenarios associated with sabotage, terrorism, and war. 

The quantitative dose-response assessment involves two different challenges, namely to determine the relationship between doses and the frequency of cases of cancer (i.e., potency evaluation), and to determine what statistical risk is tolerable or acceptable. This section gives a very short overview of some general aspects related to the quantitative dose-response assessment. The currently used approach by the WHO, the US-EPA, and the EU, as well as new approaches for the risk assessment of compounds that are both genotoxic and carcinogenic, are presented in Sections 6.3 and 6.4, respectively. 

An exposure assessment is the quantitative or qualitative evaluation of the amount of a substance that humans come into contact with and includes consideration of the intensity, frequency and duration of contact, the route of exposure (e.g., dermal, oral, or respiratory), rates (chemical intake or uptake rates), the resulting amount that actually crosses the boundary (a dose), and the amount absorbed (internal dose). Depending on the purpose of an exposure assessment, the numerical output may be an estimate of the intensity, rate, duration, and frequency of contact exposure or dose (the resulting amount that actually crosses the boundary). For risk assessments of chemical substances based on dose-response relationships, the output usually includes an estimate of dose (WHO/IPCS 1999). 

CPQRA A chemical process quantitative risk analysis is the process of hazard identification followed by numerical evaluation of incident consequences and frequencies, and their combination into an overall measure of risk when apphed to the chemical process industry. It is particularly applicable to episodic events. It differs from, but is related to, a probabilistic risk assessment (PRA), a quantitative tool used in the nuclear industry. 

SESSION II Risk Theory and Risk Analysis for Landslides. [1] Landslide Risk Management concepts and framework and examples (2.5 h) [2] Deterministic and Probabilistic models for slope stability evaluation (2 h) [3] Introduction to modelling of catastrophic landslide events (2 h) [4] Empirical models for travel distance (1.5 h) [5] Application examples of probabilistic methods and semi quantitative methods for landslide hazard zonation (2h) [6] Landslide Frequency Assessment (1.5 h) [7] Different components of vulnerability to landslides. Prevention and long term management of landslides (3.5 h) [8] Case Studies coal waste dump risk assessment, example from motorway in La Reunion Island, Aknes Rock slope in Norway (2 h) [9] Application of QRA to other geotechnical problems Internal erosion of dams, crater lake hazard (1.5 h) [10] Advanced numerical models initiation of landslides, propagation of sediments/climate change effects (3.5 h). 

From the calculated building damage versus response relationship and the empirical probability of serious injury or fatality versus damage relationship discussed above, the relationship between explosion overpressure (or other effects) and probability of serious injury or fatality may be constructed in a manner that accounts for the detailed structural characteristics of plant buildings. The steps involved are similar to risk screening (Chapter 4), with the addition of detailed quantitative structural evaluation of plant buildings and detailed quantitative frequency assessment as described in the next section. 

Nowadays, there is an increasing interest in system protection against intentional threats of physical nature [8,19]. On those regards, model-based vulnerability assessment is a crucial phase in the risk analysis of critical infrastructures. In fact, typical risk models include the computation of three logically sequential factors probability or frequency of threats (P) probability that threats are successful in their intent (i.e., vulnerability, V) consequences of successful threats (i.e., expected damage, D). Therefore, in order to evaluate infrastructure risks (R), it is essential to be able to compute the vulnerability of the system with respect to the threats [11]. One of the most widespread and intuitive model for the evaluation of the risk is [21] R = P V D. This model is based on a quantitative notion of vulnerability, different from other definitions also commonly used,... 

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