Introduction

Benefit-Cost Analysis Software for Tornado and Hurricane Shelters

This software was prepared for the use of the Federal Emergency Management Agency (FEMA) in conducting benefit-cost analyses of hazard mitigation projects for tornado and hurricane shelters.

Hazard mitigation projects are specifically aimed at reducing or eliminating future damages.  Although hazard mitigation projects may sometimes be implemented in conjunction with the repair of damages from a disaster, the focus of hazard mitigation projects is on strengthening or improving buildings to enhance their ability to withstand the impacts of future disasters.

Benefit-cost analysis compares the "benefits" and "costs" of a proposed hazard mitigation project.  For tornado and hurricane shelters, the only benefits considered are avoided future deaths and injuries in the shelter that are expected to occur as a result of the mitigation project.  In other words, benefits are the reduction in expected future deaths and injuries (i.e., the difference in expected future deaths and injuries before and after the mitigation project).  These benefits are monetized using Federal guidelines for loss of life and injury.  The costs considered are those necessary to implement and maintain the specific mitigation project under evaluation.


Hardware Requirement

Hardware and Software Requirements

The Benefit-Cost Analysis Model for Tornado and Hurricane Shelters is a stand-alone software application.  The application requires

-IBM-compatible computer (PC) with Pentium 90MHz or higher microprocessor.

-VGA 1024 X 768 or higher resolution screen supported by Microsoft Windows.

-24MB RAM for Windows 95, 32MB for Windows NT and Windows 98.

-Hard drive with at least 50 MB of free disk space.

-CD-ROM drive.

-Microsoft Windows 95 or later or Microsoft Windows NT 3.51 or later.

-Adobe Acrobat Reader 4.0 or later.  The CD contains software to install Acrobat Reader on several platforms.  Alternatively, the software can be downloaded from www.adobe.com.


Software Installation

It is recommended to close all other applications before installing the software.  For NT users, be sure you have software installation privileges for your computer or have your system administrator install the software.

1.	From Windows, run Setup.exe from the CD-ROM.  One way to do this is to use Window Explorer to navigate to the CD-ROM drive and double-clicking on the Setup.exe file.  Also, the Run command under the Start button can be used to type d:/Setup.exe, where d: should be substituted by the actual letter for the CD-ROM drive.

2.	The setup program will initially copy some of the necessary files and check your system configuration.  Depending on the configuration, the installation program may ask you if you want to update these files.  In this case you will need to restart your computer and run Setup.exe again after the machine reboots.  After this step has been completed, you will be prompted to start the software installation by clicking on the OK button.  You can also cancel the installation program by clicking on the Exit button.

3.	If you clicked OK, the next screen will contain the options to Exit, to change the installation directory, and to install the software to the specified directory.

By clicking the Change Directory button, you will have the option to change the directory where the software will be installed.  The selected hard drive should have at least 50 Mb of free space.  If you type the name of a folder that does not exist, you will be asked if you want this folder to be created.

After the installation directory has been set, click the button with the computer and disk graphic to start the software installation.  The program will ask you to choose a name for the program group under which the model will reside.  The installation software will then proceed to copy to your hard drive all of the required files.  A status window will show the progress and the files being installed.

During the installation process, you may be prompted about whether to overwrite an existing file with a new file from the installation program.  The typical situation is when the setup program detects a dll file with the same name as the one about to be installed.  In many cases, the file being written by the installation program is a more recent version of the dll in the computer and could replace the existing file.  If you are unsure, you may skip overwriting the file; however, there is a chance that the benefit-cost software may not operate properly.

The install program will copy files to the specified installation directory and the Windows system, will update the registry, and will add a new item under the Windows taskbar Start button, Programs menu: Tornado and Hurricane Shelter Mitigation.  This item contains the following:

Benefit Cost Model	Starts the model
Benefit Cost Model Help	Opens the model’s help file
User’s Guide	Opens the pdf document containing this User’s Guide.
Evaluation Checklists	Opens a pdf document containing the wind hazard evaluation checklist (described in FEMA Publication 361 Design and Construction Guidance for Community Shelters)

The User’s Guide and Evaluation Checklists are copied to a folder labeled Tornado & Hurricane BC Model, under the destination selected for installation of the program.  These files can also be found in the installation CD.

4.	After all of the files have been copied and the registry updated, the installation program will display a window that indicates that the software installed correctly.  Click the OK button and the installation program will close.  Before running the model for the first time, be sure to restart your computer.

After the software is installed a shortcut can be created on the desktop by clicking on the Windows Start button, Tornado and Hurricane Mitigation and right-clicking on Benefit Cost Model and dragging it to the desktop.


Uninstalling the Software

The install program automatically creates an uninstall procedure for the software.  It will delete all files and directories created by the install program.

1.	In the Start button, select the Settings and Control Panel.

2.	In the Control Panel window, double-click the Add/Remove Programs icon.

3.	In the Add/Remove Programs window, under the Install/Uninstall tab, select from list the Tornado and Hurricane Benefit Cost Model item and click the Add/Remove button.

4.	The install procedure will remove all files and directories installed by the install program.  It will also remove the Programs menu item for the software.  You may be prompted about removing shared files.  Usually you do not uninstall shared files, since other programs may require those files.  You may also be notified if there was a problems deleting certain files or directories.

5.	A window will indicate when the software has been completely uninstalled but it is possible that some items could not be removed.  It is recommended that you complete the uninstall by manually deleting the folder containing the files.  Be sure to restart the machine before attempting to reinstall the software.


Project Descriptive Information Screen

The Project Descriptive Information screen asks for basic information about the shelter.  The most important item in this screen is the selection of a state and county.  The program covers all 50 states and the District of Columbia, Puerto Rico, the Virgin Islands, American Samoa, and Guam.  The model only requires that the user select a state and a county.

Along the top of the screen there is a menu that controls project files, report generation, and navigation.  Along the bottom are the navigation buttons.  Dimmed navigation buttons indicate the screen being displayed.  The Benefit Cost Analysis button and menu will only become active when all of the required data has been entered.  Menu items that are not active also appear dimmed.


Building Information Screen

The Building Information screen asks for information about the shelter, dimensions and construction type, and the occupancy of the shelter during tornado and hurricanes.  All fields on this screen must have a value entered.

The building length and width are used to estimate the exposure to tornadoes.  The shelter area corresponds to that section of the building retrofitted to withstand high winds.  This area may be less than or equal to the building footprint area but cannot exceed it.

The shelter construction can be any of six standard types:

-reinforced and precast concrete

-reinforced masonry

-unreinforced masonry

-steel

-wood

-user-entered.

Damage functions for death and injury have been provided as defaults for these construction types.  The user must carefully examine these damage functions to ensure that they represent conditions in the structure being analyzed.  A sixth category labeled User-Entered has been provided for buildings that do not fall into any of the standard types.  The user must supply the damage functions when this type is selected.

The default damage curves also depend on the surface area of the building envelope covered by windows.  If the windows account for more than 7 percent of the surface area, the corresponding check box should be cleared.

Usually, hurricane occupancy can be predicted based on the maximum capacity of the shelter because hurricanes can be forecast well in advance for people to travel to the shelter.  These people are assumed to remain in the shelter for the duration of the hurricane.  In non-hurricane regions, the hurricane occupancy should always be set to zero, since the shelter will only be used against tornado hazards.

The unpredictability of tornadoes makes it likely that the people in the building at the time the tornado occurs will be the ones to head for the shelter.  Therefore, the shelter occupancy is equal to the building occupancy, which may vary hourly.

The Occupancy Check status box indicates whether the hurricane and tornado occupancy exceeds shelter area standards of 5 square feet per person during a tornado and 10 square feet per person during a hurricane.


Tornado Hazard Information Screen

The Tornado Hazard Information screen allows the user to select a group of counties to calculate tornado statistic.  For the program to calculate the probability of tornado occurrence in the selected region, the database must have a sufficient number of past tornadoes.  Because tornadoes are infrequent events, it is unlikely that a single county will have experienced a sufficient number of tornadoes for meaningful statistics.  Therefore, the sample area must typically be comprised of several counties around the target county.

The target county is shown in green and is always part of the sample area.  Other counties in the statistical sample area are shown in red.  The user can right-click on any county to view its name.  The status box below the selection options indicates whether the group of counties has a sufficient number of past tornadoes to compute tornado statistics.

Three different methods are provided to select counties.  Region Around County allows the user to select a given radius around the target county.  All counties within that radius will be used as the sample area.  Entire State selects all of the counties in the state of interest.  User Selected Counties allows the user to select individual counties, and can also be used to modify areas selected with the other two methods.  The sample area cannot be modified by clicking on individual counties in this screen.

When the Edit Counties button corresponding to the User Selected Counties option is pressed, the User Selected Counties screen appears.  This option is seldom used.  Unless there are site-specific conditions that justify odifying the selection, the user should let the software select counties according to a specified radius.  If modified, the selection should be such that the counties in the sample area are all contiguous. The user can click on individual counties to add or remove them from the statistical sample area.  Clicking on white counties adds them to the sample area.  Clicking on red counties removes them from the sample area.

The changes are confirmed or ignored using the three buttons to the right on the User Selected Counties screen.  Done returns to the Tornado Hazard Information screen with the new county selection.  Reset clears all counties except the target county.  Cancel ignores changes and returns to the Tornado Hazard Information screen.  Like the Tornado Hazard Information screen, the User Selected Counties screen also contains a status box that indicates when a sufficient number of counties has been selected.


Mitigation Project Information Screen

The Mitigation Project Information screen contains the last data that the user must enter before a Benefit-Cost Analysis can be performed.  The screen asks for the costs associated with the mitigation project, along with the project lifetime and discount rate.  The user also enters monetary values for injuries and deaths, since the program determines benefits based on reduction of injuries and deaths.

The program contains default values for potential injuries and deaths to shelter occupants.  The pre-mitigation default values are based on the construction type selected on the Building Information screen.  The mitigation effectiveness indicates what percent of pre-mitigation injuries and deaths will be avoided by implementing the proposed mitigation.  Default values for mitigation effectiveness are based on the Design Wind Speed selected from the provided drop-down list.  Figure 2-2 in the FEMA publication 361 Design and Construction Guidance for Community Shelters contains a map with the design wind speeds for the U.S.  This map is also on page 16 of the Evaluation Checklists pdf file that was installed with the model.  The program uses the effectiveness to calculate post-mitigation injuries and deaths.  The user can override any of the defaults by entering other values in the corresponding column.


Benefit Cost Analysis Screen

Once all of the required information has been entered, both the navigation menu and button that invoke the Benefit Cost Analysis screen become active.

This screen requires no user input and displays the results of the benefit-cost analysis.  The screen shows the expected annual benefits of the mitigation for tornadoes and hurricanes.  Annualized project costs are calculated, based on the project lifetime and discount rate.  The expected annual net benefits are the difference between the benefits and the costs; a positive value indicates a cost-effective project.  A Benefit Cost Ratio of 1.0 or greater is also indicative of cost-effectiveness.  The expected number of deaths and injuries avoided over the project lifetime, due to the proposed mitigation, are also shown.


Print Preview Screen

After a benefit-cost analysis has been performed, the Print Preview and Print items in the File menu become active.  The short report is a one page summary of the inputs and results of the benefit-cost analysis. The long report is a seven-page report giving detailed information about the program input data, the hazard statistics, and the results of the benefit-cost analysis.  The Print Preview screen allows the user to view and print the report.

The toolbar along the top of the Print Preview screen allows the user to print the report, view the report at different magnifications levels, and navigate through the report pages. From left to right, the first icon in the toolbar controls a table of contents (which is not used).  The second icon, with the printer graphic and the word “Print…”, activates the print command, which displays a screen where the user can select the printing options.  The Print screen also allows access to printer setup commands.

The next three icons control the magnification of the print preview.  The + and – magnifying glass icons zoom in and out on the current page of the report.  The drop box with percentages also controls the magnification of the current page.

The final five icons relate to navigation through a report and are only active for the long report.  The page up and down arrow icons will cause the screen to go to the previous or next page in the report.  The window next to these icons indicates the current page number and the total page number.  Finally, the back and next buttons can also be used to navigate through the report pages.

The Print Preview screen can manually be resized or moved by clicking with the mouse on the screen border and dragging to the desired size or location.  The screen can be closed by clicking on the X icon on the upper right corner of the screen.

In addition, the screen can be resized, moved, or closed using the Window menu, which is activated by clicking on the tornado icon in the upper left corner of the screen (before the screen title).  The Window menu is available on all screens in the model.


New Item

New

New creates a new project file.  After prompting the user to save the current project, all program screens will be cleared for the new project.


Open Item

Open

Open loads an existing project file.  The program stores projects with the .tor extension.  After prompting the user to save the current project, a browse window will open that allows the user to load a project file from any directory.  The selected file will load and all screens will be updated with the selected file’s information.


Save Item

Save

Save saves the current project file.  If the file has previously been saved, Save will use the existing file name.  If the file has not been saved before, the user will be prompted for a file name.


Save As Item

Save As

Save As prompts the user for a file name for the current project.


Print Preview Item

Print Preview

Print Preview allows the user to preview either the short or long format reports generated by the program after a benefit cost analysis has been performed.  The reports can be printed from the preview window.


Print Item

Print

Print allows the user to print either the short or long format reports generated by the program after a benefit-cost analysis has been performed.


Exit Item

Exit

Exit will close the program after prompting the user to save the current project.


Cut Item

Cut

Cut deletes selected text from its current location and copies it to the clipboard.


Copy Item

Copy

Copy places selected text in the clipboard without deleting it from its location.


Paste Item

Paste

Paste places text currently in the clipboard into the selected location.


Input Menu

Input Menu Information

The Input menu provides navigation between the four input information screens. Selecting one of the four menu items switches the application to the corresponding screen.


BC Analysis Menu
BC Analysis Results Menu Item

The BC Analysis menu contains one item only that provides navigation to the Benefit-Cost Analysis screen.


Help Menu

The Help menu loads the Help file for the program.  Throughout the program, the F1 key loads topic-specific help.


Navigation Buttons

Navigation Button Information

The Navigation Buttons are an alternate way to navigate between screens.  The button for the active screen is dimmed. Clicking any of the buttons switches to the corresponding screen. The Benefit Cost Analysis button is dimmed until all of the required information has been entered.


Start New Project File

Start

To start, click the Windows Taskbar Start Button.  Select Programs and then Tornado and Hurricane Shelter Mitigation. Finally, select Benefit Cost Model.

Select New Project from the Opening screen and click OK.


Project Descriptive Information

Enter Project Descriptive Information

After the Project Descriptive Information screen is displayed, enter the information shown below.  The mouse or tab key will navigate through the input fields.

Building Name	Lanier Elementary School
Address	Thompson Bridge Road
City	Gainsville
State	Georgia (Use drop-down list)
County	Hall (Use drop-down list)
Disaster Number	NA
Project Number	1
Scenario Run ID	1
Analyst	FEMA

Note that the county dropdown box will not contain any choices unless a state has been selected.  The software will not allow switching to another screen unless a state and county have been selected.

Click on the Building Information Button to go to the Building Information screen.


Building Information

Enter Building Information

Enter the information shown below into the Building Information screen.  The mouse or tab key will navigate through the input fields.  As you enter the data, you will notice that the message in the Occupancy Check status box will change.

Building Longest Length	500 ft
Building Longest Width	200 ft
Shelter Area	5000 ft2
Shelter Construction Type	Reinforced & Precast Concrete (Use drop-down list)
Checkbox for “Building has minimal window area (less than 7% of wall area)”	Checked
Hurricane Shelter Occupancy	100 people
Tornado Shelter Occupancy	0 for 12 am through 6 am
	200 people for 7 am
	581 people for 8 am through 1 pm
	200 people for 2 pm through 4 pm
	20 people for 5 pm through 6 pm
	100 people for 7 pm through 9 pm
	0 for 10 pm through 11 pm
Time Zone	Automatically chosen by program as Eastern ST
Checkbox for Daylight Savings	Automatically checked by the program

The status box will warn the user when the occupancy exceeds 5 ft2/person during tornadoes or 10 ft2/person during hurricanes.

Click on the Tornado Hazard Button to go to the Tornado Hazard Information screen.


Tornado Hazard Information

Enter Tornado Hazard Information

When you first enter this screen, only Hall County will be selected (shown in green) and none of the county selection options will be active.  The computer will beep whenever the selected counties do not have a sufficient number of tornadoes to compute hazard probabilities.

Click on Region Around County.  After you select Region Around County, a slider bar and text box will appear. A slider bar and text box will appear to select a region around Hall County from which tornado statistics will be derived.  In the majority of cases, one county alone has not experienced enough tornadoes to calculate meaningful statistics.

Click on the slider bar once or drag it to advance the radius from 0 to 50 miles.  You can also type the radius value in the text box and hit Enter.  After this is done, you will need to wait a few moments while the program queries the national tornado database determines if the selected counties have sufficient tornado occurrences for statistical analysis.  The status box will read “Calculating” until the selection and calculation are complete.

You will notice that the newly selected counties are in red, while Hall County remains green.  Also notice that the map scale resets to show Georgia, South Carolina, and North Carolina, since the selected counties fall within these states.

Clicking User Selected Counties allows manual addition or deletion of counties to the statistical sample area.  This option is seldom used.  Unless there are site-specific conditions that justify modifying the selection, the user should let the software select counties according to a specified radius.  If modified, the selection should be such that the counties in the sample area are all contiguous.

For this tutorial, assume that you only want to use counties in Georgia.  To remove the counties in other states, click the Edit Counties button.  The User Selected Counties screen should appear as shown below.  This screen allows you to add or remove individual counties.  Using the mouse, left click on the red counties that are not in Georgia.  As you click on these counties, they will change from red to white and the status window will recalculate and show whether there is a sufficient number of tornadoes.  Clicking on white counties will add them to the selected region.

When you have removed all counties not in Georgia, the view will zoom in to only Georgia. To keep these selected counties, click the Done button to return to the Tornado Hazard Information screen.  The Reset button deselects all counties except Hall County.  The Cancel button closes this window and returns to the Tornado Hazard Information screen with the selection unchanged.

When you return to the Tornado Hazard Information screen, the map will be identical to the one you created on the User Selected Counties screen.  Now that you have selected your counties for tornado statistics, click the Mitigation Project Information button to go to that screen. A popup window with a progress bar indicates that tornado statistics are being extracted from the tornado database.


Mitigation Project Information

Enter Mitigation Project Information

In the Mitigation Project Information screen, enter the following information:

Mitigation Project Description	Strengthened Hallway
Project Cost	$225,793
Maintenance Cost	$0 (Default)
Project Lifetime	30 years
Discount Rate	7 % (Default)
Injury Cost	$12,500 / injury (Default)
Death Cost	$2,200,000 / death (Default)
Design Wind Speed	200 mph
User-Defined Pre-Mitigation Injury and Death Curves	Enter 0 only in the first 3 wind ranges for injury and death.

Default values will be used for all other pre-mitigation and mitigation effectiveness boxes that are left blank.  This input assumes that the building withstands a wind speed of up to 118 mph in its current state; therefore, no deaths or injuries are expected.

This screen contains many default values.  When you enter a value for the Project Lifetime, you will notice that the Benefit Cost Analysis button and menu become active.  This indicates that all of the data necessary to perform a benefit-cost analysis have been entered.

Click the Benefit Cost Analysis button to perform the benefit cost analysis.


BC Analysis Results

After a brief pause for calculation, the Benefit Cost Analysis screen will show the results of the analysis.  For the project data entered, the project is cost-effective, with a Benefit Cost Ratio of 7.17 and an Expected Annual Net Benefit of $112,291 per year.


Save Project File
Save project

To save the project just created, click on the File menu and Save.

Navigate to the directory of your choice and in the File name: box, enter a name for the file.  The program will save the project as <your_file_name>.tor.

You have now successfully entered and saved a tornado and hurricane shelter project!

To Exit the program, select the File menu and Exit.  You will always be prompted to save your current project.  Select No, since you just saved your project.


Open Project Save

Opening Project

There are two ways to open an existing file.  When you first start the program, you can select the Existing File option.  Also, if you are already in the program, you can use the File menu and Open to open an existing file.

Open “gaschool.tor”, a sample project file installed with the program.  You can only have one project open at a time.


Print Preview

After the file has been loaded, you will notice that the Benefit Cost Analysis button and menu items are active.  As mentioned before, this indicates that the project has sufficient information to perform a benefit costs analysis.  This also indicates that Print and Print Preview in the File menu are active.  In the File menu, select Print Preview, Long Report.

The long report is a seven-page document that gives details on the input data, hazard statistics, and benefit cost results.  Pages 1 through 4 list the input data entered in the Project Descriptive Information, Building Information, Tornado Hazard Information and Mitigation Project Information screens.  Page 5 shows a summary of the tornado statistics associated with the project and page 6 summarizes the extreme wind statistics.  Finally, page 7 shows the Benefit Cost Analysis information and remarks on the options chosen by the user.  These remarks DO NOT indicate that an error was made, only that the user must be carefully reviewed.

To zoom in or out on the current page, use the + and – magnifying glass icons or the drop-down box with the percent zoom.  To scroll through the pages, use the up and down arrow page icons.  Back and Forward become active after you have scrolled through several pages.

Once you have previewed the report, use the print icon to send the file to the printer.  After you click OK to print the report, you will be returned to the Print Preview screen.  To exit the Print Preview screen, click on the icon in the upper left corner and select Close or click the X icon in the upper right corner of the screen.


Print

There are two methods to print the long and short reports.  One method uses Print in the Print Preview screen.  The second method to print a report uses the File menu, Print.

Select the File menu, Print for the Short Report.  You will notice that the Print range for pages is dimmed since the short report is only one page long.  Click OK to print this report.  You will then be returned to your original screen.


Data: Project Descriptive Information
Project Descriptive Information

Data required for the Project Descriptive Information screen is mainly for project documentation.

Project Descriptive Information

Input	Data Source
Building Name	Descriptor to identify building.
Address	Project location.
City	Project location.
State	Project location (required).
County	Project location (required).
Disaster Number	Assigned by FEMA for declared disasters, available at FEMA’s web page (www.fema.gov).
Project Number	Assigned by FEMA, state, or municipality for project management purposes.
Scenario Run ID	Assigned by analyst for comparison of alternatives (optional).
Analyst	Name of person or organization performing analysis.


Data: Building Information
Building Information

The data required for the Building Information screen come from design information about the proposed project.

Building Information

Input	Data Source
Building Longest Length	Building footprint.
Building Longest Width	Building footprint.
Shelter Area	Project design data; should not exceed building area.
Shelter Construction Type & Window Area	Project design data.
Hurricane Shelter Occupancy	Project design information, should not cause less than 10 sq.ft./person.
Hourly Tornado Shelter Occupancy	Project design information, should not cause less than 5 sq.ft./person.
Time Zone	Project location, default based on selected county.
Daylight Savings	Project location, default based on selected county.

The building length and width should be the longest dimensions of the sides of the entire building where a shelter is located, even if the shelter is located in only part of the building.  These dimensions help define the “target area” for tornadoes.  The shelter area is only that area of the building that is used during an emergency.

The shelter construction categories are:

-Reinforced & Precast Concrete

-Reinforced Masonry

-Unreinforced Masonry

-Steel

-Wood

-User-Defined

Window Categories are:

-Less than 7% of wall area

-Greater than 7% of wall area

Each combination of construction and window categories, with the exception of the User-Defined category, are associated with a corresponding pre-mitigation injury and death percentage for each wind range, which are given as defaults on the Mitigation Project Information screen.

Usually, hurricane occupancy can be predicted based on the maximum capacity of the shelter because hurricanes can be forecast well in advance for people to travel to the shelter.  These people are assumed to remain in the shelter for the duration of the hurricane.  The unpredictability of tornadoes makes it likely that the people in the building at the time the tornado occurs will be the ones to head for the shelter.  Therefore, the shelter occupancy at any given time in the day is equal to the building occupancy.  The occupancy input should be based on the project design of the shelter, where occupants during a hurricane should have at least 10 square feet and occupants during a tornado should have at least 5 square feet.  The program automatically adjusts the average hourly occupancy value if a location observes daylight savings.  For those counties that contain two time zones or different observances of daylight savings, the user should adjust the time zone and daylight savings as necessary so that the occupancy shown is representative of average conditions.  In non-hurricane regions, the hurricane occupancy should always be set to zero, since the shelter will only be used against tornado hazards.


Data: Tornado Information

Tornado Hazard Information

The program has an extensive database of tornado information for each county in the U.S collected by the National Atmospheric and Oceanic Administration (NOAA).  This database is used to compute tornado probability of occurrence.  The user must select a set of counties to calculate the tornado statistics for the project location.  A status box indicates when a sufficient number of counties has been chosen to produce meaningful tornado statistics.

The actual selection of counties depends on the scope of the project and the analyst’s knowledge of tornadoes around the project location.  In most cases, selecting a region within a given radius around a county will provide a sufficient tornadoes.  However, for smaller states or for statewide planning purposes, the entire state of interest may be appropriate.

The User-Selected Counties option should only be used when the analyst has site-specific information that supports the selection of a specific group of counties.  For example, tornado occurrence has been shown to depend on relief; therefore, the user may want to include in the sample only counties with similar terrain characteristics.  Another situation in which manual modifications may be needed is when it is politically undesirable to include counties in neighboring states.

In any case, manual selection of counties should produce a region comprised of contiguous counties.  The long report lists all of the counties in the statistical sample region broken down by state.  The user or reviewer can use this list to verify the continuity of the sample region.


Data: Mitigation Project Information
Mitigation Project Information

The data required for the Mitigation Project Information screen comes from mitigation project planning and analysis of potential damages in the event of a hurricane or tornado.

Mitigation Project Information

Input	Data Source
Mitigation Project Description	Descriptor for mitigation project (not required)
Project Cost	Capital cost of implementing the project
Maintenance Cost	Annual operating and maintenance expenses
Project Lifetime	Expected useful life of the project (usually 30 to 50 years)
Discount Rate	User-selected discount rate.  Federally funded projects use 7%.
Injury Cost	Monetized injury damages.  The Federal Aviation Administration (FAA) uses $12,500 per injury.
Death Cost	Monetized loss-of-life damages.  The FAA uses $2,200,000 per death.
Design Wind Speed	From Figure 2-2 in FEMA publication 361 Design and Construction Guidance for Community Shelters and on page 16 of the Evaluation Checklists.
Injury: Pre-Mitigation	Evaluation of current building condition.  Default curves are provided for given building types.
Injury: Mitigation Effectiveness	Estimated protection provided by mitigation project.  Default curves are provided for selected design wind speeds.
Injury: Post-Mitigation	Calculated based on pre-mitigation and mitigation effectiveness.
Death: Pre-Mitigation	Evaluation of current building condition.  Default curves are provided for given building types.
Death: Mitigation Effectiveness	Estimated protection provided by mitigation project.  Default curves are provided for selected design wind speeds.
Death: Post-Mitigation	Calculated based on pre-mitigation and mitigation effectiveness.

The mitigation project description provides general information about the proposed mitigation project.  The project cost should include all one-time costs to implement the mitigation project, while the maintenance cost should include annual costs to insure that the project functions properly.  Both cost figures should only account for additional costs to construction from implementing the mitigation project.  For example, if building has been planned to withstand 150 mph winds, but a mitigation project is proposed to strengthen it to 200 mph, then the costs should only include the additional measures needed to strengthen the structure.  Often the total construction cost can be prorated by a construction expert or contractor that is familiar with the additional costs for strengthening a shelter against stronger winds.

The project lifetime is the useful life of the mitigation project.  The discount rate is used for present value calculations and has a default value of 7% for FEMA funded projects.

The injury and death costs assign a dollar value to human injury and death.  The Federal Aviation Administration (FAA) has estimated defaults for major injury and death of $12,500 and $2,200,000, respectively.

The Design Wind Speed is the 3-second gust wind in miles per hour (mph) that the FEMA publication 361 Design and Construction Guidance for Community Shelters recommends for shelters.  Figure 2-2 in this publication provides the geographic distribution of these values.  This map is also on page 16 of the Evaluation Checklists file that was installed with the model.

The last set of information estimates percent injury and death associated with structural failure at different wind speed ranges.  The pre-mitigation values have defaults based on the construction type and window coverage selected on the Building Information screen.  These default values for pre-mitigation must be adjusted to account for local building codes and standards and the current condition of the building.  Most communities require structures to be built, at a minimum, to withstand certain wind levels.  The pre-mitigation default values do not consider these standards, since they vary through the country, and the user must enter values consistent with these standards.  For example, a shelter may have been designed based on a local minimum design wind speed of 100 mph.  In the User-Defined Pre-Mitigation columns for injury and death, zeroes should be entered for all wind ranges up to and including 100 mph.

Similarly, the mitigation effectiveness values should be adjusted if the default mitigation effectiveness does not fully reflect the actual mitigation design.

Supporting documentation must accompany any analysis that requires these kinds of adjustments.

The model is intended to analyze the economic feasibility of retrofitting an existing building to install a shelter capable of withstanding high winds.  This includes adding a shelter to an existing building.  However, the software can also be used to evaluate cost-effectiveness of constructing a new building, where the entire building will be used as a shelter.  In this case, the user needs to select the User-Defined option in the Shelter Construction Type dropdown box in the Building Information screen and supply the damage and mitigation effectiveness curves in the Mitigation Project Information screen.  The loss data must accurately reflect the injuries and deaths expected in the population expected to use the shelter. These deaths and injuries must be computed based on the locations where the targeted population is anticipated to be when the wind event occurs, if the shelter is not constructed.  The development of these data is not a trivial task and requires careful examination of site conditions and consultation with wind engineers, community planners, and emergency response professionals.