FLORIDA GEOGRAPHIC DATA LIBRARY DOCUMENTATION TITLE: PANEL AREAS OF THE DIGITAL FLOOD INSURANCE RATE MAP (DFIRM) IN THE STATE OF FLORIDA - OCTOBER 2017 Geodataset Name: DFIRM_PANEL_OCT17 Geodataset Type: SHAPEFILE Geodataset Feature: Polygon Feature Count: 7214 |
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GENERAL DESCRIPTION:
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DATA SOURCE(S): Federal Emergency Management Agency SCALE OF ORIGINAL SOURCE MAPS: 12000 GEODATASET EXTENT: State of Florida |
FEATURE ATTRIBUTE TABLES:
Datafile Name: DFIRM_PANEL_OCT17.DBF
ITEM NAME | WIDTH | TYPE |
OBJECTID
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4 | OID |
SHAPE
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4 | Geometry |
DFIRM_ID
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6 | String |
VERSION_ID
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11 | String |
FIRM_ID
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32 | String |
ST_FIPS
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2 | String |
PCOMM
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4 | String |
PANEL
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4 | String |
SUFFIX
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1 | String |
FIRM_PAN
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11 | String |
PANEL_TYP
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30 | String |
PRE_DATE
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36 | Date |
EFF_DATE
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36 | Date |
SCALE
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5 | String |
PNP_REASON
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254 | String |
BASE_TYP
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10 | String |
SOURCE_CIT
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21 | String |
XMIN
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4 | Integer |
YMIN
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4 | Integer |
XMAX
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4 | Integer |
YMAX
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4 | Integer |
PRODUCT_ID
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20 | String |
DESCRIPT
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15 | String |
FGDLAQDATE
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36 | Date |
AUTOID
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4 | Integer |
SHAPE.AREA
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0 | Double |
SHAPE.LEN
|
0 | Double |
FEATURE ATTRIBUTE TABLES CODES AND VALUES:
Item | Item Description | |
OBJECTID |
Internal feature number. |
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SHAPE |
Feature geometry. |
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DFIRM_ID |
Study Identifier. For a single-jurisdiction flood risk project, the value is composed of the two-digit State FIPS code and the four-digit FEMA CID code (e.g., 480001). For a countywide flood risk project, the value is composed of the two-digit State FIPS code, the three-digit county FIPS code, and the letter "C" (e.g., 48107C). Within each FIRM Database, the DFIRM_ID value will be identical. |
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VERSION_ID |
Version Identifier. Identifies the product version and relates the feature to standards according to how it was created.
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FIRM_ID |
Primary key for table lookup. Assigned by table creator. |
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ST_FIPS |
State FIPS. This is the two - digit code that corresponds to the State Federal Information Processing Standard (FIPS) code. This is a standard numbering system used by the Federal government, defined in FIPS Pub 6-4. These two numbers correspond to the first two digits of the panel number. Acceptable values for this field are listed in the D_State_FIPS table.
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PCOMM |
Community or County Identification Number. This is the third through the sixth digits of the panel number. For community based maps this corresponds to the FEMA Community Identification number. For countywide maps this is the county (or county equivalent) FIPS code with a "C." |
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PANEL |
Panel Number. This is seventh through the 10th digits in the complete panel number. This is assigned by the scale of the map and the position within the community or county. The panel number scheme is described in detail in the FIRM Panel Technical Reference. |
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SUFFIX |
Map Suffix. This is the final digit in the complete panel number. This is a letter suffix at the end of the panel number. The map suffix is incremented one letter every time the panel gets republished.
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FIRM_PAN |
FIRM Panel Number. This is the complete 11-digit FIRM panel number, which is made up of ST_FIPS, PCOMM, PANEL, and SUFFIX. This is the FIRM panel number that is shown in the title block of the map. |
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PANEL_TYP |
Panel Type. The type of FIRM panel identifies whether the panel is printed or not, and whether it is community based or countywide. Acceptable values for this field are listed in the D_Panel_Typ table.
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PRE_DATE |
Preliminary Release Date. This is the preliminary release date of the current map revision. This field is not populated until the FIRM preliminary release date is established and the Prelim FIRM is ready for hardcopy production by the Mapping Partner. Then it is required. |
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EFF_DATE |
Effective Date. This is the effective date of the current map revision. This field is not populated until the FIRM effective date is established and the Final FIRM is ready for hardcopy production by FEMA. Then it is required. |
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SCALE |
Map Scale. This is the denominator of the FIRM scale as a ratio. For example, 24000 is the denominator for a 1'' = 2000' map. Acceptable values for this field are listed in the D_Scale table.
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PNP_REASON |
Panel Not Printed Reason. This is the explanation for the FIRM panels that are not printed. Only completed if the hardcopy panel is not printed by FEMA. For example "No Special Flood Hazard Areas." See the FIRM Panel Technical Referencefor commonly used values. |
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BASE_TYP |
Base map type. The type of base map used for the FIRM panel shall be recorded in this field. Acceptable values for this field are listed in the D_Basemap_Typ table.
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SOURCE_CIT |
Source Citation. Abbreviation used in the metadata file when describing the source information for the feature. The abbreviation must match a value in L_Source_Cit. |
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XMIN |
Feature's Extent X Minimum location. |
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YMIN |
Feature's Extent Y Minimum location. |
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XMAX |
Feature's Extent X Maximum location. |
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YMAX |
Feature's Extent Y Maximum location. |
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PRODUCT_ID |
FEMA Flood Map Service Center Product ID. https://msc.fema.gov/portal/advanceSearch
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DESCRIPT |
Based on field [FIRM_PAN]. |
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FGDLAQDATE |
Date FGDL acquired the data from the Source. |
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AUTOID |
Unique ID added by GeoPlan |
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SHAPE.AREA |
Area in meters |
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SHAPE.LEN |
Perimeter in meters |
The DFIRM Database is made up of several data themes containing both spatial and attribute information. These data together represent the current flood risk for the subject area as identified by FEMA. The attribute tables include SFHA locations, flood zone designations, BFEs, political entities, cross-section locations, FIRM panel information, and other data related to the NFIP. |
When FEMA revises an FIS, adjacent studies are checked to ensure agreement between flood elevations at the boundaries. Likewise flood elevations at the confluence of streams studied independently are checked to ensure agreement at the confluence. The FIRM and the FIS are developed together and care is taken to ensure that the elevations and other features shown on the flood profiles in the FIS agree with the information shown on the FIRM. However, the elevations as shown on the FIRM are rounded whole-foot elevations. They must be shown so that a profile recreated from the elevations on the FIRM will match the FIS profiles within one half of one foot. |
Data contained in the NFHL reflects the content of the source materials. Features may have been eliminated or generalized on the source graphic, due to scale and legibility constraints. With new mapping, FEMA plans to maintain full detail in the spatial data it produces. However, older information is often transferred from existing maps where some generalization has taken place. Flood risk data are developed for communities participating in the NFIP for use in insurance rating and for floodplain management. Flood hazard areas are determined using statistical analyses of records of river flow, storm tides, and rainfall; information obtained through consultation with the communities; floodplain topographic surveys; and hydrological and hydraulic analysis. Generally, regulatory water surface elevations and/or regulatory floodways are published only for developed or developing areas of communities. For areas where little or no development is expected to occur, FEMA may generate flood risk data without published water surface elevations. Typically, only drainage areas that are greater than one square mile and with an average of one foot of flood depth or greater are studied. Note: The NFHL reflects the most current information available when the distribution data set was created. Currently, not all areas of a State or Territory have effective FIRM Database data. As a result, users may need to refer to the effective FIRM for effective flood hazard information. |
The NFHL incorporates all FIRM Databases published by FEMA and any LOMRs that have been issued against those databases since their publication date. The NFHL consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. Attribute accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. Independent quality control testing of the individual FIRM Database components of the NFHL was also performed. To obtain more detailed information in areas where Base Flood Elevations (BFEs) and/or floodways have been determined, users are encouraged to consult the Flood Profiles and Floodway Data and/or Summary of Stillwater Elevations tables contained within the FIS reports that accompany the individual FIRM Database components of the NFHL. Users should be aware that BFEs shown in the S_BFE table may represent rounded whole-foot elevations. These BFEs are intended for flood insurance rating purposes only and should not be used as the sole source of flood elevation information. Accordingly, flood elevation data presented in the FIS report must be used in conjunction with the FIRM for purposes of construction and/or floodplain management. The 1-percent- annual-chance water-surface elevations shown in the S_XS table match the regulatory elevations shown in the FIS report. |
-------------------------------------------------------------------------------- **The Following Information Contains The GeoPlan Center Process Steps: Indented Format** The GeoPlan Center downloaded the Statewide National Flood Hazard Layer from the following FEMA website on October 13th, 2017. FEMA Flood Map Service Center https://msc.fema.gov/portal Search All Products https://msc.fema.gov/portal/advanceSearch Choose one of the three search options below and optionally enter a posting date range. https://msc.fema.gov/portal/advanceSearch State -FLORIDA County - ALACHUA Community - ALACHUA Search Effective Products NFHL Data-State(1) Product ID Latest Study Effective Date Latest LOMR Effective Date Size Download NFHL_12_20171006 10/05/2017 10/06/2017 1975MB NFHL_12_20171006.zip NFHL_12_20171006.gdb Feature Layer: S_FIRM_Pan The S_FIRM_Pan was originally in the following projection: GCS_North_American_1983 WKID: 4269 Authority: EPSG Angular Unit: Degree (0.0174532925199433) Prime Meridian: Greenwich (0.0) Datum: D_North_American_1983 Spheroid: GRS_1980 Semimajor Axis: 6378137.0 Semiminor Axis: 6356752.314140356 Inverse Flattening: 298.257222101 The dataset was projected to the FGDL Albers HARN projection using the following Transformation: NAD_1983_To_HARN_Florida The dataset was renamed to dfirm_panel_oct17. Next the following fields were added and populated: PRODUCT_ID = "NFHL_12_20171006" DESCRIPT = [FIRM_PAN] FGDLAQDATE = "10/13/2017" AUTOID = OBJECTID + 1 No methodology was performed by GeoPlan to correct for geometry issues. For more information on FEMA's Final Data Structure concerning sliver polygons please see below. The FEMA report frm_gsal.pdf states the following regarding sliver polygons. L.3.5.2 Topology Vector data files must meet the following data structure requirements: * Area spatial features for a given theme must cover the entire study area without overlaps, underlaps or sliver polygons between adjacent polygons. -------------------------------------------------------------------------------- |
The FIRM is the basis for floodplain management, mitigation, and insurance activities for the National Flood Insurance Program (NFIP). Insurance applications include enforcement of the mandatory purchase requirement of the Flood Disaster Protection Act, which "... requires the purchase of flood insurance by property owners who are being assisted by Federal programs or by Federally supervised, regulated or insured agencies or institutions in the acquisition or improvement of land facilities located or to be located in identified areas having special flood hazards, " Section 2 (b) (4) of the Flood Disaster Protection Act of 1973. In addition to the identification of Special Flood Hazard Areas (SFHAs), the risk zones shown on the FIRMs are the basis for the establishment of premium rates for flood coverage offered through the NFIP. The FIRM Database presents the flood risk information depicted on the FIRM in a digital format suitable for use in electronic mapping applications. The FIRM Database serves to archive the information collected during the Flood Risk Project. |
The NFHL consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. Horizontal accuracy was tested by manual comparison of source graphics with hardcopy plots and a symbolized display on an interactive computer graphic system. Independent quality control testing of the individual FIRM Database components of the NFHL was also performed. |
The NFHL consists of vector files and associated attributes produced in conjunction with the hardcopy FEMA FIRM. The published effective FIRM and FIRM Database are issued as the official designation of the SFHAs. As such they are adopted by local communities and form the basis for administration of the NFIP. For these purposes they are authoritative. Provisions exist in the regulations for public review, appeals and corrections of the flood risk information shown to better match real world conditions. As with any engineering analysis of this type, variation from the estimated flood heights and floodplain boundaries is possible. Details of FEMA's requirements for the FISs and flood mapping process that produces these data are available in the Guidelines and Standards for Flood Risk Analysis and Mapping. The reliability of the floodplain boundary delineation is quantified by comparing the computed flood elevation to the ground elevation at the mapped floodplain boundary. The tolerance for how precisely the flood elevation and the ground elevation must match varies based on the flood risk class, which is a function of population, population density, and/or anticipated growth in floodplain areas. A horizontal accuracy of +/- 38 feet is used to determine the compliance with the vertical tolerances defined for each risk class. The range of differences between the ground elevation (defined from the topographic data used for the Flood Risk Project) and the computed flood elevation is between +/- 1.0 foot at the 95% confidence interval for areas with high population within the floodplain and/or high anticipated growth and Special Flood Hazard Areas (SFHAs) with high flood risk to +/- one-half the contour interval at the 85% confidence interval for areas with low population and densities within the floodplain and small or no anticipated growth and SFHAs with low flood risk. Independent quality control testing of the individual FIRM Database components of the NFHL was also performed. |
FEMA Disclaimer: No warranty expressed or implied is made by FEMA regarding the utility of the data on any other system nor shall the act of distribution constitute any such warranty. FEMA will warrant the delivery of this product in a computer-readable format, and will offer appropriate adjustment of credit when the product is determined unreadable by correctly adjusted computer input peripherals, or when the physical medium is delivered in damaged condition. Requests for adjustment of credit must be made within 90 days from the date of this shipment from the ordering site. The hardcopy FIRM and FIRM Database and the accompanying FIS are the official designation of SFHAs and Base Flood Elevations (BFEs) for the NFIP. For the purposes of the NFIP, changes to the flood risk information published by FEMA may only be performed by FEMA and through the mechanisms established in the NFIP regulations (44 CFR Parts 59-78). These digital data are produced in conjunction with the hardcopy FIRMs and generally match the hardcopy map exactly. Acknowledgement of FEMA would be appreciated in products derived from these data. |
The Florida Geographic Data Library is a collection of Geospatial Data compiled by the University of Florida GeoPlan Center with support from the Florida Department of Transportation. GIS data available in FGDL is collected from various state, federal, and other agencies (data sources) who are data stewards, producers, or publishers. The data available in FGDL may not be the most current version of the data offered by the data source. University of Florida GeoPlan Center makes no guarantees about the currentness of the data and suggests that data users check with the data source to see if more recent versions of the data exist. Furthermore, the GIS data available in the FGDL are provided 'as is'. The University of Florida GeoPlan Center makes no warranties, guaranties or representations as to the truth, accuracy or completeness of the data provided by the data sources. The University of Florida GeoPlan Center makes no representations or warranties about the quality or suitability of the materials, either expressly or implied, including but not limited to any implied warranties of merchantability, fitness for a particular purpose, or non-infringement. The University of Florida GeoPlan Center shall not be liable for any damages suffered as a result of using, modifying, contributing or distributing the materials. A note about data scale: Scale is an important factor in data usage. Certain scale datasets are not suitable for some project, analysis, or modeling purposes. Please be sure you are using the best available data. 1:24000 scale datasets are recommended for projects that are at the county level. 1:24000 data should NOT be used for high accuracy base mapping such as property parcel boundaries. 1:100000 scale datasets are recommended for projects that are at the multi-county or regional level. 1:125000 scale datasets are recommended for projects that are at the regional or state level or larger. Vector datasets with no defined scale or accuracy should be considered suspect. Make sure you are familiar with your data before using it for projects or analysis. Every effort has been made to supply the user with data documentation. For additional information, see the References section and the Data Source Contact section of this documentation. For more information regarding scale and accuracy, see our webpage at: http://geoplan.ufl.edu/education.html |
FEMA Flood Map Service Center https://msc.fema.gov/portal/advanceSearch Additional Documentation For more information on this dataset and its creation process, please see the metadata attached to the downloadable data and the following from FEMA: NFHL Resources http://www.fema.gov/national-flood-insurance-program-flood-hazard-mapping/national-flood-hazard-layer-nfhl National Flood Hazard Layer (NFHL): New Products and Services for FEMA's Flood Hazard Map Data http://www.fema.gov/media-library/assets/documents/13424?id=3286 NFHL GIS Data: Perform Spatial Analyses and Make Custom Maps and Reports http://www.fema.gov/media-library/assets/documents/13476?id=3291 Guidelines and Standards for Flood Risk Analysis and Mapping http://www.fema.gov/guidelines-and-standards-flood-risk-analysis-and-mapping Technical References http://www.fema.gov/media-library/assets/documents/34519 Guidance Documents http://www.fema.gov/media-library/assets/documents/34953 Map Modernization http://www.fema.gov/national-flood-insurance-program-flood-hazard-mapping/map-modernization |
The NFHL dataset is a compilation of effective FIRM Databases (a collection of the digital data that are used in GIS systems for creating new Flood Insurance Rate Maps) and Letters of Map Change (Letters of Map Amendment and Letters of Map Revision only) that create a seamless GIS data layer for a State or Territory. It is updated on a monthly basis. The FIRM Databases are compiled in conjunction with the hardcopy FIRMs and the final FIS reports. The specifics of the hydrologic and hydraulic analyses performed are detailed in the FIS reports available for each jurisdiction. The results of these studies are submitted in digital format to FEMA. These data and unrevised data from effective FIRMs are compiled onto the base map used for FIRM publication and checked for accuracy and compliance with FEMA standards. As new FIRM Databases are received the individual FIRM layers are sewn into the nationwide layers of the NFHL. LOMRs for the FIRM Databases in the NFHL are cut directly into the NFHL data layers as they are being produced and finalized. Process Date: 20171006 |
Projection ALBERS Datum HPGN Units METERS Spheroid GRS1980 1st Standard Parallel 24 0 0.000 2nd Standard Parallel 31 30 0.000 Central Meridian -84 00 0.000 Latitude of Projection's Origin 24 0 0.000 False Easting (meters) 400000.00000 False Northing (meters) 0.00000
DATA SOURCE CONTACT (S):
Name: Abbr. Name: Address: Phone: Web site: E-mail: Contact Person: Phone: E-mail: |
Federal Emergency Management Agency National Flood Hazard Layer 500 C Street SW Washington, DC 20472 1-800-358-9616 |
Name: FLORIDA GEOGRAPHIC DATA LIBRARY Abbr. Name: FGDL Address: Florida Geographic Data Library 431 Architecture Building PO Box 115706 Gainesville, FL 32611-5706 Web site: http://www.fgdl.org Contact FGDL: Technical Support: http://www.fgdl.org/fgdlfeed.html FGDL Frequently Asked Questions: http://www.fgdl.org/fgdlfaq.html FGDL Mailing Lists: http://www.fgdl.org/fgdl-l.html For FGDL Software: http://www.fgdl.org/software.html