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The Basic CAPTool Guide 79 Step 2: Thresholds Introduction In Step 2, the user sets the consequence threshold assets and asset classes. The consequence threshold is the point set by the owner, operator, or system user that goes beyond the effects of routine disruptions and losses that current preparations and responses are designed to manage. Setting a consequence threshold focuses attention on the relevant assets, eliminating from fur- ther consideration those assets that cannot exceed consequence thresholds, regardless of the haz- ard or threat. The consequence threshold is used to identify assets or asset classes to be included and the extent to which the hazards and threats identified in Step 1 are retained in the assessment. Thresholds are set for each asset class and for each consequence category. The threshold is used to identify assets that are to be considered in later steps as candidates for countermeasure appli- cation. The user can adjust the threshold for any of the consequences to determine how such changes might affect the number and types of assets that remain on the high-consequence list and thus are candidates for investment of additional resources. Purpose The objective of this step is to establish the consequence threshold beyond which the asset owner, operator, or system user would consider investments in countermeasures to prevent losses or mitigate consequences. Definitions Consequence--An indication of the negative effects from an event on assets of interest. Assets of interest are typically people, structures, or equipment. Direct Consequence--The loss of life, or injury, to a person or damage or destruction of property. Indirect Consequence--Adverse social, economic, or psychological effects resulting from an event. Consequence Threshold--A planning factor used to set the level of consequences beyond which additional investments in countermeasures may be justified. The user may choose this level because beyond it, the physical, economic, or mission damages cannot be readily restored with available resources. The choice of a threshold does not mean that losses below this level are unimportant or inconsequential; it means that losses below this level can be managed operationally and within the existing resources of the agency. Assumptions 1. The consequence levels chosen are consistent with an agency's intent to commit resources to eliminate or mitigate consequences that exceed the threshold. 2. The user can alter and adjust the threshold levels in subsequent iterations with the CAPTool. User Input User inputs in this step establish the consequence thresholds for each of these consequence categories for each asset category (Figure 4). This step requires the user to select a combination of consequence thresholds. The user will select threshold values for each of the consequence areas consistent with the level of responsibility and concern the user acknowledges. The threshold selected is not meant to imply that losses below the threshold are of no consequence, but that losses below the selected threshold are within responsibilities and concern of other entities (e.g., subordinate jurisdictions

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80 1 2 3 4 5 6 Basic CAPTool Reset Thresholds Jump to Critical CAPTool User Guide 1 1a 2 3 4 5a 5b 5c 5 6 Expanded CAPTool Previous Next Assets Summay to Lowest Levels Establish Consequence Thresholds Instructions (Only if Data on For each asset class, set the appropriate thresholds. Individual Assets is When done, click "Next." Already Entered "Reset" sets all thresholds to their lowest levels. Category Critical Threshold Explanation ROAD BRIDGE Potentially Exposed Population 0 Potentially exposed population threshold Property Loss $5,000 Replacement cost Mission Importance Level I Demand percentile for ADT * Detour Length Level I 29000 The default threshold values for ADT * detour length are taken from the 75th, 85th, Level II 68000 Restore Defaults and 95th percentiles for the U.S. If these are inappropriate for your state, enter Level III 241000 different values in the appropriate fields to the left. ROAD TUNNEL Potentially Exposed Population 0 Potentially exposed population threshold Property Loss $5,000 Replacement cost Mission Importance Yes Do you consider all road tunnels to be mission critical? TRANSIT/RAIL Potentially Exposed Population 0 Potentially exposed population threshold STATION Property Loss Yes Do you consider below-ground stations to be property critical? Mission Importance Yes Do you consider all transfer stations to be mission critical? TRANSIT/RAIL Potentially Exposed Population 0 Potentially exposed population threshold BRIDGE Property Loss $5,000 Replacement cost Mission Importance 0 What % of ridership does a bridge need to serve in order to be mission critical? TRANSIT/RAIL Potentially Exposed Population 0 Potentially exposed population threshold TUNNEL Property Loss $5,000 Replacement cost Mission Importance 0 What % of ridership does a tunnel need to serve in order to be mission critical? ADMIN & SUPPORT Potentially Exposed Population 0 Potentially exposed population threshold FACILITIES Property Loss $5,000 Replacement cost Mission Importance Yes Do you consider all administrative and support facilities to be mission critical? FERRY BOATS Potentially Exposed Population 0 Potentially exposed population threshold Property Loss $5,000 Replacement cost Mission Importance Yes Do you consider all ferry boats to be mission critical? TRANSIT FLEETS Potentially Exposed Population 0 Potentially exposed population threshold Property Loss $5,000 Replacement cost Mission Importance Yes Do you consider all transit fleets to be mission critical? Figure 4. Consequence threshold values.

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The Basic CAPTool Guide 81 or agencies or offices within agencies). The losses below the threshold may be within the means of response for the agency. The user begins by identifying consequence thresholds where additional capital investments might be considered. This consequence can be adjusted through successive iterations but identi- fies an outcome that is considered worthy of avoiding and may require investments in counter- measures. The level of investment is determined in Step 5. After seeing the resource implications of a selected consequence threshold, the decision maker may choose to raise or lower the thresh- old to determine how the costs vary with changes in the threshold values. For the purposes of this step, the body of previous work in this area provides the basis for the consequence categories. When applied to particular assets or asset classes, consequence categories assume total destruction of the asset. The following consequence categories are used in Step 1: Potentially Exposed Population: This category is expressed in terms of potential casualties. The expression is a range of casualties for each threshold level. The CAPTool uses the phrase "poten- tially exposed population" (PEP) because the analysis assumes that this is the upper bound on harm to people associated with the maximum threat. Therefore, the reference is to exposure to risk rather than an estimate of the actual casualties resulting from the hazard or threat. Property Loss: This category is expressed in terms of asset replacement costs. The expression is in millions of dollars across the cost range. Mission Importance: This category is expressed in terms of loss of function and/or transport delays and is relevant to specific assets or asset classes, including the relative importance of assets to the transportation network as indicated by their system role (e.g., Interstate Highway System, National Highway System designation) and the volume of use (e.g., Average Daily Traf- fic (ADT)) across a volume range. For highway bridges, the CAPTA uses the product of ADT and detour distance as a surrogate for mission or function impact. The user can set the values of this factor based on local data. For purposes of illustration, this CAPTool example uses the 75, 85, and 95 percentile of this product based on bridges in the National Bridge Inventory. Note that other major consequences may also occur, including loss of specific government services, delays to emergency response, and impediments to military deployment. However, such consequences tend to be highly correlated with the primary consequences that capture loss of life; loss of property; and disruption of functions and related economic, government, military, and emergency response activities. The consequence categories are provided as a starting point so that decision makers may make an initial pass through the process and then, through feedback and adjustments, converge on solutions that make sense within the context for which they are developed. Output The product of this step is the user-selected consequence thresholds by consequence cate- gories. The information entered into CAPTool during this step is used in identifying assets and asset classes that are judged to be of high consequence (critical) and will remain in the analysis for further consideration. ATA Example As shown in Figure 5, ATA's available resources, including additional capital from the state legislature and bond markets, enable it to set a consequence threshold of about $100 million for sustaining damages to infrastructure. ATA is realistic about casualties, setting thresholds appro- priate to the mode of transportation, averaging 100 potentially exposed persons. It does not con- sider its transit fleets to be critical to the mission of the agency.

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82 1 2 3 4 5 6 Basic CAPTool Reset Thresholds Jump to Critical CAPTool User Guide 1 1a 2 3 4 5a 5b 5c 5 6 Expanded CAPTool Previous Next Assets Summay to Lowest Levels Establish Consequence Thresholds Instructions (Only if Data on For each asset class, set the appropriate thresholds. Individual Assets is When done, click "Next." Already Entered "Reset" sets all thresholds to their lowest levels. Category Critical Threshold Explanation ROAD BRIDGE Potentially Exposed Population 200 Potentially exposed population threshold Property Loss $101,699,661 Replacement cost Mission Importance Demand Percentile II Demand percentile for ADT * Detour Length Level I 29000 The default threshold values for ADT * detour length are taken from the 75th, 85th, Level II 68000 Restore Defaults and 95th percentiles for the U.S. If these are inappropriate for your state, enter Level III 241000 different values in the appropriate fields to the left. ROAD TUNNEL Potentially Exposed Population 101 Potentially exposed population threshold Property Loss $101,699,661 Replacement cost Mission Importance No Do you consider all road tunnels to be mission critical? TRANSIT/RAIL Potentially Exposed Population 100 Potentially exposed population threshold STATION Property Loss Yes Do you consider below-ground stations to be property critical? Mission Importance Yes Do you consider all transfer stations to be mission critical? TRANSIT/RAIL Potentially Exposed Population 200 Potentially exposed population threshold BRIDGE Property Loss $100,004,750 Replacement cost Mission Importance 20 What % of ridership does a bridge need to serve in order to be mission critical? TRANSIT/RAIL Potentially Exposed Population 200 Potentially exposed population threshold TUNNEL Property Loss $100,004,750 Replacement cost Mission Importance 20 What % of ridership does a tunnel need to serve in order to be mission critical? ADMIN & SUPPORT Potentially Exposed Population 101 Potentially exposed population threshold FACILITIES Property Loss $101,699,661 Replacement cost Mission Importance No Do you consider all administrative and support facilities to be mission critical? FERRY BOATS Potentially Exposed Population 305 Potentially exposed population threshold Property Loss $101,699,661 Replacement cost Mission Importance No Do you consider all ferry boats to be mission critical? TRANSIT FLEETS Potentially Exposed Population 50 Potentially exposed population threshold Property Loss $100,004,750 Replacement cost Mission Importance No Do you consider all transit fleets to be mission critical? Figure 5. ATA consequence threshold choices.