Hazard Identification & Risk Analysis Flashcards

Which step in the THIRA (Threat and Hazard Identification and Risk Assessment) process involves establishing desired outcomes for each threat or hazard?

Answer: Establish capability targets

Step 3 of THIRA—Establish Capability Targets—defines the specific outcomes a community needs to achieve in response to each threat or hazard scenario.

In probabilistic seismic hazard analysis (PSHA), the output is typically expressed as:

Answer: Ground motion levels with specified probabilities of exceedance over a time period

PSHA produces hazard curves showing the annual probability of exceeding various ground motion levels, often expressed as a 2% or 10% probability of exceedance in 50 years.

The 'annualized loss estimate' used in hazard mitigation planning represents:

Answer: The expected average annual losses calculated from probability-weighted damage estimates

Annualized loss estimates multiply the probability of each loss scenario by its expected damage to produce an average expected annual loss figure.

Which organization publishes the National Risk Index, a dataset ranking U.S. counties by natural hazard risk?

Answer: FEMA

FEMA's National Risk Index combines expected annual loss data, social vulnerability, and community resilience scores to rank counties by composite natural hazard risk.

In a bow-tie risk diagram, the left side (fault tree) depicts _____, while the right side (event tree) depicts _____.

Answer: Threats leading to a hazard event; consequences following a hazard event

A bow-tie diagram combines fault tree analysis on the left (threats/causes leading to the top event) with event tree analysis on the right (consequences and recovery paths).

Which vulnerability indicator is most associated with technological and industrial hazard risk assessments?

Answer: Proximity of sensitive populations to hazardous facilities

In technological hazard assessments, the proximity of sensitive populations—such as schools or nursing homes—to industrial facilities is a critical vulnerability indicator.

A 'maximum probable loss' (MPL) estimate in risk analysis represents:

Answer: The worst loss expected under realistic adverse conditions, excluding catastrophic scenarios

MPL estimates the largest loss likely under unfavorable but realistic conditions, excluding extreme low-probability catastrophic scenarios often used for insurance underwriting.